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  • 1
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    On the multi-fractal characteristics of the ULF geomagnetic field before the 1993 Guam earthquake (2013)
    Copernicus Publications
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: Ida et al. (2005) document significant changes in the multi-fractal parameters of the ULF geomagnetic field H component starting about one month before the 1993 Guam earthquake. According to the authors, these multi-fractal signatures can be considered as precursory signals of the Guam earthquake. As a consequence, they conclude that the multifractal analysis may have an important role in the development of short-term earthquake prediction capabilities. Since this and other similar reports have motivated the idea that earthquake prediction based on electromagnetic precursory signals may one day become a routine technique, the presumed precursors need to be validated through independent datasets. In this review the seismogenic origin of the multifractal magnetic signatures documented by Ida et al. (2005) before the 8 August 1993 Guam earthquake is seriously put into question. By means of the geomagnetic ΣKp index, it is demonstrated that these multi-fractal parameter changes are normal signals induced by the variation of the global geomagnetic activity level.
    Beschreibung: Published
    Beschreibung: 187-191
    Beschreibung: 2.6. TTC - Laboratorio di gravimetria, magnetismo ed elettromagnetismo in aree attive
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): Geomagnetic field ; Magnetic anomalies ; Earthquake precursors ; Seismology ; 04. Solid Earth::04.05. Geomagnetism::04.05.04. Magnetic anomalies
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 2
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    Comment on “Ultra Low Frequency (ULF) European multi station magnetic field analysis before and during the 2009 earthquake at L’Aquila regarding regional geotechnical information” by Prattes et al. (2011) (2012)
    Copernicus Publications
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: Prattes et al. (2011) report ULF magnetic anomalous signals claiming them to be possibly precursor of the 6 April 2009 MW6.3 L’Aquila earthquake. This comment casts doubts on the possibility that the observed magnetic signatures could have a seismogenic origin by showing that these pre-earthquake signals are actually part of normal global geomagnetic activity.
    Beschreibung: Published
    Beschreibung: 1717–1719
    Beschreibung: 2.6. TTC - Laboratorio di gravimetria, magnetismo ed elettromagnetismo in aree attive
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): Geomagnetic field ; Earthquake precursors ; Magnetic anomalies ; Seismology ; 04. Solid Earth::04.05. Geomagnetism::04.05.99. General or miscellaneous ; 04. Solid Earth::04.05. Geomagnetism::04.05.04. Magnetic anomalies ; 04. Solid Earth::04.06. Seismology::04.06.99. General or miscellaneous
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 3
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    Core-mantle boundary topography: seismology (2012)
    Springer
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: n/a
    Beschreibung: Published
    Beschreibung: 125-127
    Beschreibung: 3.3. Geodinamica e struttura dell'interno della Terra
    Beschreibung: restricted
    Schlagwort(e): Core-mantle boundary topography ; Seismology ; 04. Solid Earth::04.01. Earth Interior::04.01.03. Mantle and Core dynamics
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 4
    Digitale Medien
    Digitale Medien
    Suitability of new and old association hosts for the development of selected microgastrine parasitoids of gramineous stemborers (1999)
    Springer
    Entomologia experimentalis et applicata 90 (1999), S. 257-266 
    Details
    ISSN: 1570-7458
    Schlagwort(e): host suitability ; acceptance ; biological control ; new associations ; Lepidoptera ; Pyralidae ; New World ; Old World ; stemborers ; Braconidae ; larval parasitoids ; Gramineae
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The present study examined the acceptability and suitability of Old World stemborers (Chilo partellus and C. orichalcociliellus) for the development of New World parasitoids (Apanteles deplanatus and A. minator) and New World stemborers (Diatraea saccharalis and D. grandiosella) for the development of Old World parasitoids (Cotesia sesamiae, C. flavipes and C. chilonis). Results revealed that acceptance and suitability were high in old associations. In new associations, parasitoids accepted about 60% of the new association hosts. In addition, 10 out of 17 new associations were successful. Apanteles species appeared to be more physiologically host specific than Cotesia species. For example, two of four new association hosts were accepted by A. deplanatus and only one (D. saccharalis) was partially suitable for progeny development. Among the Cotesia species, Cotesia flavipes appeared to have a wider host range than the two other species. It attacked all hosts offered and successfully parasitized all but one (D. grandiosella). Diatraea saccharalis was accepted and was a suitable host for the development of all parasitoid species tested, whereas D. grandiosella was unsuitable for the development of four out of five parasitoid species tested. No clear pattern was observed as behavioral acceptance did not always agree with the pattern of physiological suitability. Implications of these findings for importation biological control of stemborers are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1026435617979
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  • 5
    Digitale Medien
    Digitale Medien
    Ostrinia spp. in Japan: their host plants and sex pheromones (1999)
    Springer
    Entomologia experimentalis et applicata 91 (1999), S. 237-244 
    Details
    ISSN: 1570-7458
    Schlagwort(e): host plant range ; sex pheromone ; Ostrinia furnacalis ; Ostrinia latipennis ; Ostrinia nubilalis ; Ostrinia orientalis ; Ostrinia palustralis ; Ostrinia scapulalis ; Ostrinia zaguliaevi ; Ostrinia zealis ; Lepidoptera ; Pyralidae
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract To contribute to the understanding of the genus Ostrinia (Lepidoptera; Pyralidae) in Japan, we collected larvae of Ostrinia spp. from known host plants and plants not recorded as hosts, and we examined the morphology and sex pheromones of the adults obtained. Consequently, the host plant ranges of the 7 Ostrinia spp. in Japan were clarified, and the sex pheromones of the 5 species O. scapulalis, O. zealis, O. zaguliaevi, O. palustralis and O. latipennis were identified in addition to that of the Asian corn borer O. furnacalis. The phylogenetic relationships of Japanese Ostrinia spp., with reference to the European corn borer O. nubilalis, are discussed based on these findings and results of molecular phylogenetic analyses.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003601407578
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  • 6
    Digitale Medien
    Digitale Medien
    Role of visual cues and interaction with host odour during the host-finding behaviour of the cabbage moth (1999)
    Springer
    Entomologia experimentalis et applicata 91 (1999), S. 59-65 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Lepidoptera ; Noctuidae ; Mamestra brassicae ; host-finding behaviour ; visual cues ; host-choice ; interaction ; odour ; volatiles
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The approach and landing responses of female Mamestra brassicae (L.) (Lepidoptera: Noctuidae) to visual cues from artificial plant leaves of different shapes and presence/absence of cabbage plant odour were investigated in a laboratory wind tunnel. The leaves were painted with cadmium yellow colour and observed under dim red light. Females showed oriented flight towards plant odours but landed significantly more often when the odour was presented with an artificial leaf. In three-choice tests, the shape of the leaf targets (circle, square or triangle) did not influence the female response. However, the size of the target did influence the insect response: the females preferred landing on square targets with sides of 5 or 10 cm rather than on the largest target, with sides of 15 cm. The orientation of the target influenced the insects' response: females landed significantly more often on the target positioned vertically than horizontally.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003605125191
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  • 7
    Digitale Medien
    Digitale Medien
    Vive la variance: a functional oviposition theory for insect herbivores (1999)
    Springer
    Entomologia experimentalis et applicata 91 (1999), S. 187-194 
    Details
    ISSN: 1570-7458
    Schlagwort(e): oviposition ; strategy ; catastrophe ; theory ; clutch ; Lepidoptera ; optimization ; dynamic ; bet hedging
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We developed state-dependent life-history theory to explain the variance in clutch size decisions made by insect herbivores under a variety of ecological scenarios. An important aspect of our theory is explicit representation of the distribution of host quality and frequency of occurrence. Examination of the theory suggests that clutch size decisions can be highly non-linear with respect to host quality and variability. We then use our theory to explore the potential for bet-hedging strategies to evolve as a function of unpredictable catastrophic events that decimate entire clutches. Our analysis suggests that the benefits to employing such a strategy will frequently be outweighed by costs brought on by delayed oviposition.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003622703384
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  • 8
    Digitale Medien
    Digitale Medien
    The role of volatiles from cruciferous plants and pre-flight experience in the foraging behaviour of the specialist parasitoid Cotesia plutellae (1999)
    Springer
    Entomologia experimentalis et applicata 93 (1999), S. 87-95 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Lepidoptera ; Yponomeutidae ; Plutella xylostella ; parasitoid ; Hymenoptera ; Braconidae ; Cotesia plutellae ; foraging behaviour ; wind tunnel
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The braconid Cotesia plutellae is an important larval parasitoid of the diamondback moth (Plutella xylostella), a major pest of crucifers in the tropics and sub-tropics. The in-flight searching behaviour of C. plutellae was investigated in a wind tunnel and the close-range attack behaviour observed in cages. The relative importance of volatile stimuli emanating from the plant-host-complex, oilseed rape (Brassica napus) – P. xylostella, in the long-range attraction of C. plutellae was investigated. Plants that were mechanically damaged, or damaged by P. xylostella larvae, were attractive to the parasitoid. Host-damaged leaves remained attractive to the parasitoid after removal of the host larvae. These results indicate that C. plutellae predominantly uses plant derived stimuli in its in-flight searching behaviour. An oviposition experience or contact with a host-damaged leaf prior to the bioassay significantly increased the response to these volatile cues. The foraging behaviour of C. plutellae is compared with other braconid larval parasitoids attacking lepidopteran hosts on crucifers.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003822208843
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  • 9
    Digitale Medien
    Digitale Medien
    Adult female and neonate larval plant preferences of the generalist herbivore, Epiphyas postvittana (1999)
    Springer
    Entomologia experimentalis et applicata 92 (1999), S. 53-62 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Lepidoptera ; Tortricidae ; host selection ; correlation ; lightbrown apple moth
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The polyphagous leafroller moth, Epiphyas postvittana, is a pest of many fruit crops in New Zealand. Since the larva is highly mobile, host selection in this insect may involve both the adult female and the larva. In order to test the relative importance of the adult female and the neonate larva in the selection of host plants, the ovipositional preferences of females, and the preferences or acceptances of neonate larvae towards 26 plant species, consisting of 15 plants considered hosts and 11 not considered hosts, were investigated. In the ovipositional tests, the mean preferences of females for hosts and non-hosts were very similar. In contrast, larvae showed a significantly greater mean preference or acceptance towards hosts than to non-hosts, in both choice and no-choice bioassays, respectively. There were highly significant correlations between the preferences and acceptances of larvae for plants in the choice and no-choice tests. In the no-choice tests, there was a highly significant correlation between the acceptances of neonate larvae towards plants after one and three days (i.e., acceptances changed little over time). Moreover, in these no-choice tests, there was a significant negative correlation between larval acceptance at 1 day and larval mortality after 3 days; that is, the less acceptable a given plant at 1 day, the more likely larvae would fail to establish, feed, and survive on it by three days. Female and larval preferences towards the various plants were also negatively correlated. Together, these data suggest that the selection of a plant for the neonate larva to feed on is largely governed by the preferences of the larva, rather than by the preferences of the female. However, selection of a plant for oviposition by the female, may be important in host selection for reasons unrelated to larval preferences, for example, by encouraging dispersal, perhaps to other plant species, of the neonate larvae and thereby decreasing intersibling competition.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003760529540
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  • 10
    Digitale Medien
    Digitale Medien
    Reidentification of the female sex pheromone of the Indian meal moth, Plodia interpunctella: evidence for a four-component pheromone blend (1999)
    Springer
    Entomologia experimentalis et applicata 92 (1999), S. 137-146 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Lepidoptera ; Pyralidae ; Plodia interpunctella ; Indian meal moth ; pheromone components ; GC-EAD ; stored-product pest ; behaviour ; flight tunnel ; trapping ; Ephestia kuehniella
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Pheromone gland extracts from calling female Plodia interpunctella contained at least seven compounds that consistently elicited electroantennographic responses from male antennae upon gas chromatographic analysis. Three of these compounds were found to be the previously identified gland constituents, i.e., (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:OAc), (Z,E)-9,12-tetradecadienal (Z9,E12-14:Ald) and (Z,E)-9,12-tetradecadienol (Z9,E12-14:OH). A fourth EAD-active compound was identified as (Z)-9-tetradecenyl acetate (Z9-14:OAc). The homologue (Z)-11-hexadecenyl acetate (Z11-16:OAc) was also identified in the extracts, but showed no EAD activity. The identity of all five compounds was confirmed by comparison of GC retention times and mass spectra with those of synthetic standards. In flight tunnel tests there were no significant differences in response of male P. interpunctella to the bait containing all four EAD-active compounds and the responses to female gland extacts. A behavioural assay of different two-compound blends in the flight tunnel showed that only addition of the corresponding aldehyde to the major pheromone component Z9,E12-14:OAc raised the male response. A subtractive assay, however, revealed that the exclusion of any of the compounds from the complete four-compound blend reduced its activity significantly. We thus conclude that the female-produced sex pheromone of P. interpunctella consists of at least four components, i.e., Z9,E12-14:OAc, Z9,E12-14:Ald, Z9,E12-14:OH and Z9-14:OAc. In a field trapping test performed in a storage facility, the four-component blend attracted significantly more males of P. interpunctella than traps baited with Z9,E12-14:OAc alone. In contrast, the highest number of Ephestia kuehniella males was found in the traps baited with this major component, suggesting that the secondary pheromone components contribute to the species specificity of the blend.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003703724011
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  • 11
    Digitale Medien
    Digitale Medien
    Effect of avocadofurans on larval survival, growth, and food preference of the generalist herbivore, Spodoptera exigua (1999)
    Springer
    Entomologia experimentalis et applicata 90 (1999), S. 131-140 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Lepidoptera ; Noctuidae ; avocadofurans ; Spodoptera exigua ; avocado ; idioblast ; oil cell ; food preference
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We examined the effect of two avocadofurans, 2-(pentadecyl)furan and 2-(heptadecyl)furan, from avocado idioblast oil cells on maturation and larval feeding behavior of a generalist insect herbivore, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae). Experiments were conducted using two larval sizes: early-stadium larvae refer to those larvae from experiments initiated with neonates while late-stadium larvae refer to those larvae from experiments initiated with third instars. In order to use selected sublethal doses for developmental and behavioral studies on early- and late-stadium larvae, log-dose probit lines were determined using diet incorporation bioassays. Both avocadofurans had similar toxicities to early-stadium larvae [LC50=2.2 and 1.9 μmoles/g of diet for 2-(pentadecyl)furan and 2-(heptadecyl)furan, respectively] and late-stadium larvae (LC50=3.0 and 3.4 μmoles/g of diet, respectively). In diet bioassays extending from egg hatch to adult emergence, the avocadofurans significantly prolonged larval developmental times and reduced S. exigua pupal weights. In 7 d no-choice bioassays initiated with cohorts of newly-molted third instars, the avocadofurans significantly reduced larval weights at various sublethal concentrations (below LC50 values). To test larval feeding deterrence effects of these avocadofurans, choice tests were conducted using early and older instar larvae. A significantly higher proportion of early-stadium larvae preferred control diet over diet treated with either avocadofuran at several sublethal concentrations. Similarly, choice tests with late-stadium larvae showed greater proportions of larvae on control diet than treated diet even at concentrations below the LC50. Moreover, late-stadium larvae consumed significantly more of the control diet than the treated diet. Thus, the avocadofurans may act as feeding deterrents as well as toxicants in plant protection against non-adapted insect herbivores.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003595730600
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  • 12
    Digitale Medien
    Digitale Medien
    Pheromone-mediated mating disruption of Choristoneura rosaceana: is the most attractive blend really the most effective? (1999)
    Springer
    Entomologia experimentalis et applicata 90 (1999), S. 37-47 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Choristoneura rosaceana ; obliquebanded leafroller ; Lepidoptera ; Tortricidae ; mating disruption ; mechanisms ; pheromone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract An attractive four-component pheromone blend containing a major component Z11-tetradecenyl acetate, and three minor components, E11-tetradecenyl acetate, Z11-tetradecenyl alcohol, and Z11-tetradecenyl aldehyde was tested as a mating disruptant against western Canadian populations of the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), in organic apple orchards in British Columbia. Efficacy of this four-component blend was compared to that of partial pheromone blends containing the major component plus one or two minor components. A trapping experiment confirmed that, Conrel® fibre disruption dispensers containing the four-component blend were more attractive than disruption dispensers containing the two- or three-component partial blends. A small-plot protocol was followed to compare atmospheric treatments with these blends as mating disruptants at a release rate of 10 mg ha−1 h−1 and from 1000 dispensers ha−1. Mechanisms of mating disruption, such as false-trail following and camouflage of pheromone plumes, that may be evoked to a greater degree by an attractive blend, did not appear to augment the effectiveness of mechanisms invoked by the less attractive blends, as the proportion of mating among tethered females was equal in plots treated with these blends and was reduced by 85–90% compared to the nontreated control. When the four-component pheromone blend was tested at different release rates, mating disruption in small plots began to break down at a release rate of 1.3 mg ha−1 h−1 using a dispenser density of 1000 ha−1. Above 1.3 mg ha−1 h−1 there was no dose response in release rates tested and at release rates below this dose the proportion of tethered females mating was the same as in the nontreated control. The four-component pheromone blend was tested against, and found to be no more effective than, the two-component partial blend at the threshold release rate of 1.3 mg ha−1 h−1 when it was released from 1000 or 250 disruption dispensers. Our results suggest that disruption mechanisms evoked by the attractive blend did not enhance the mating disruption effect provided by the simple blend, therefore a two-component blend may be useful in an operational mating disruption program for C. rosaceana.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003598114512
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  • 13
    Digitale Medien
    Digitale Medien
    The diapause syndrome in the seed-eating caterpillar of Coleophora alticolella (1999)
    Springer
    Entomologia experimentalis et applicata 92 (1999), S. 321-330 
    Details
    ISSN: 1570-7458
    Schlagwort(e): rush moth ; Juncus squarrosus ; fluctuating food resources ; ‘bet-hedging’ ; Lepidoptera
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Adult emergence in Coleophora alticolella held at 15 °C was accelerated by exposure to L18:D6 in autumn and midwinter. The effect decreased during winter and exposure of individuals, held at low temperature over winter, to L18:D6 or L6:D18 at 15 °C at the end of March resulted in the same mean emergence date. Long daylength experienced at 5 °C did not promote emergence nor did exposure to low temperature during winter. The number of adults emerging increased with the length of time cultures were held on short day but was always below 50% of the larvae. When larvae were exposed to L18:D6 and L6:D18 at 15 °C at the end of March, on long day 61% adults emerged and 39% remained in diapause, whereas on short day, 25% became adult and 75% remained diapausing larvae. The possibility of cohort splitting, with some individuals undergoing prolonged diapause, is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003868005283
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  • 14
    Digitale Medien
    Digitale Medien
    Effect of plant lectins on larval development of the legume pod borer, Maruca vitrata (1999)
    Springer
    Entomologia experimentalis et applicata 93 (1999), S. 179-187 
    Details
    ISSN: 1570-7458
    Schlagwort(e): artificial diet ; insecticidal activity ; legume pod borer ; Lepidoptera ; Maruca vitrata ; plant lectins
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The legume pod-borer Maruca vitrata (Fabricius), [Lepidoptera: Pyralidae] is a major constraint restricting increased cowpea production in tropical Africa and Asia. Since lectins are known to have insecticidal properties against several pests, a survey was undertaken to screen for the effects of 25 lectins from 15 plant families on the development of Maruca pod borer (MPB) larvae. The list included 8 galactose/N-acetylgalactosamine-, 7 mannose-, 5 complex glycan-, 2 sialic acid- and 3, N-acetylglucosamine-specific lectins. Feeding bioassays using artificial diet were carried out at 2% (w/w) topical levels. Although a total of 16 lectins had detrimental effects pertaining either to larval survival, weight, feeding inhibition, pupation, adult emergence and/or fecundity, only the Listera ovata agglutinin (LOA) (Orchidaceae) and Galanthus nivalis (Amaryllidaceae) agglutinin were effective against MPB larvae for all six parameters examined. Larval mortality and feeding inhibition caused by the most active lectin (LOA) was above 60%.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003801120192
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  • 15
    Digitale Medien
    Digitale Medien
    The effects of mating, age at mating, and plant stimuli, on the lifetime fecundity and fertility of the generalist herbivore Epiphyas postvittana (1999)
    Springer
    Entomologia experimentalis et applicata 91 (1999), S. 287-295 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Lepidoptera ; Tortricidae ; oviposition ; host deprivation ; lightbrown apple moth
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The effects of mating, age at mating, the presence or absence of a plant leaf, and the deprivation of a suitable ovipositional substrate during when the first ovipositional bout after mating would normally take place, on the lifetime fecundity and fertility (percentage of fertile eggs laid) of female Epiphyas postvittana were investigated. Mating had a significant effect on lifetime fecundity, with mated females laying 2.5 times more eggs than virgin females. Age at mating had a significant effect on both fecundity and fertility, both declining with increasing age when the female was mated. In the presence of a leaf of C. japonica, mated females had a greater lifetime fecundity than when no leaf was present; females in the presence of a C. japonica leaf consistently laid more eggs each day during the first 4–6 days after mating than females without a leaf. When females were deprived of a suitable ovipositional substrate, for the first 22 h after mating, they were significantly less fecund over their lifetime than were control females. Finally, in no-choice tests with three plants of different acceptability to females, the fecundity of females differed in the order C. japonica 〉 Urtica ferox 〉 Tibouchina multiflora. This different fecundity appeared to be inversely related to the pubescence of the leaves, suggesting that leaf texture may be a suitable antixenotic resistance factor for crops to be protected from this insect. These results suggest that strategies whereby mating is delayed or oviposition reduced within a critical period after mating, may result in significant reductions in pest populations.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003674529752
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  • 16
    Digitale Medien
    Digitale Medien
    Modulation of Flight Activity in Lobesia botrana Den. & Schiff. (Lepidoptera: Tortricidae) Females Studied in a Wind Tunnel (1999)
    Springer
    Journal of insect behavior 12 (1999), S. 199-211 
    Details
    ISSN: 1572-8889
    Schlagwort(e): Lepidoptera ; Tortricidae ; Lobesia botrana ; flight activity ; wind tunnel ; atmospheric pressure ; flight experience ; mating ; age ; olfaction
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We studied modulations of flight activity in European grapevine moth females (EGVM) by individual observations in a wind tunnel. The effect of different factors was analyzed: variation in atmospheric pressure prior to the experiments, time of day, first experience of flight, age, mating, and odor of tansy, which attracts females. The circadian flight activity showed a peak the hour preceding the onset of scotophase and sustained activity occurred during the 6 h around this peak. Females with a flight experience in the tunnel took off more quickly than naive ones (3.9 ± 7.4 vs 20.3 ± 22.8 s). Three-day-old unmated females subjected to negative variations of atmospheric pressure (10 hPa) during the 4 h prior to the experiments increased their duration of flight (12.1 ± 8.7 vs 5.3 ± 3.4 s) compared to those not subjected to variation. One-day-old females were less active than older ones; flight was shorter than in 2-day-old females (2.7 ± 6.7 vs 5.1 ± 9.5 s) and fewer of them took off (28 vs 63%). Mating also affected the flight activity of 2-day-old females; mated females flew longer than virgins (12 ± 16.8 vs 5.1 ± 9.5 s) and took off more quickly (6.5 ± 14.4 vs 19.3 ± 20.1 s). Tansy odor in the tunnel did not significantly affect the flight behavior of virgin females, but it increased the proportion of mated females that initiated flight (87 vs 70%) and duration of flight (11.2 ± 24.4 vs 7.2 ± 13.7 s), and it reduced the latency to takeoff (2.1 ± 7.4 vs 8.1 ± 19.1 s). Flight duration in tansy odor was inversely correlated with the total number of eggs laid during the female's whole life. Our experimental settings did not allow observation of movements directed toward the odor source.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020914800170
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  • 17
    Digitale Medien
    Digitale Medien
    A Taxonomy of Evolutionary Algorithms in Combinatorial Optimization (1999)
    Springer
    Journal of heuristics 5 (1999), S. 145-158 
    Details
    ISSN: 1572-9397
    Schlagwort(e): evolutionary algorithms ; genetic algorithms ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Mathematik
    Notizen: Abstract This paper shows how evolutionary algorithms can be described in a concise, yet comprehensive and accurate way. A classification scheme is introduced and presented in a tabular form called TEA (Table of Evolutionary Algorithms). It distinguishes between different classes of evolutionary algorithms (e.g., genetic algorithms, ant systems) by enumerating the fundamental ingredients of each of these algorithms. At the end, possible uses of the TEA are illustrated on classical evolutionary algorithms.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009625526657
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  • 18
    Digitale Medien
    Digitale Medien
    Fine-scale resolution of closely spaced pheromone and antagonist filaments by flying male Helicoverpa zea (1999)
    Springer
    Journal of comparative physiology 185 (1999), S. 131-141 
    Details
    ISSN: 1432-1351
    Schlagwort(e): Key wordsHelicoverpa zea ; Noctuidae ; Lepidoptera ; Sex pheromone ; Antagonist
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract The limits of a male moth's ability to resolve closely spaced odor filaments have been investigated. Male Helicoverpa zea normally respond to their conspecific sex pheromone blend by exhibiting an upwind flight, which culminates in source contact by at least 50% of the bioassayed individuals. When loaded onto the same filter paper source containing this hitherto attractive pheromone blend, or onto a separate filter paper and co-emitted from the same pipette source with pheromone, (Z)-11-hexadecenyl acetate severely reduced upwind flight and source contact by male H. zea. A similar level of upwind flight inhibition was recorded when the antagonist (Z)-11-hexadecenyl acetate was emitted from its own point source placed 1 mm upwind of the pheromone point source, both plumes being simultaneously emitted in a continuous mode to form a confluent strand. However, (Z)-11-hexadecenyl acetate was less effective in reducing upwind flight and source contact when it was isolated and pulsed from its own source, placed 1 mm either upwind, downwind or cross-wind of a pipette source from which pheromone was simultaneously being pulsed, such that both filaments were separated in time by 0.001–0. 003 s. These results suggest that male H. zea are able to distinguish between odor sources separated by as little as 1 mm in space and 0.001 s in time.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s003590050372
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  • 19
    Digitale Medien
    Digitale Medien
    Trichromatic colour vision in the hummingbird hawkmoth, Macroglossum stellatarum L. (1999)
    Springer
    Journal of comparative physiology 184 (1999), S. 535-541 
    Details
    ISSN: 1432-1351
    Schlagwort(e): Key words Insects ; Lepidoptera ; Macroglossum stellatarum ; Colour vision ; Red receptor
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract Hymenopterans have long been shown to choose colours by means of the spectral distribution and independently of the intensity (true colour vision). The same ability has only very recently been proven for two butterfly species. We present evidence for the existence of true colour vision in the European hummingbird hawkmoth, Macroglossum stellatarum. Moths were trained in dual-choice situations to spectral lights of a rewarding and an unrewarding wavelength. After training, unrewarded tests were performed during which the intensities of the lights were changed. The results confirm that the species has three spectral receptor types and uses true colour vision when learning the colour of a food source. If colour vision is not possible since only one receptor type is receiving input from both stimuli, the moths learn to associate some achromatic cue correlated to the receptor quantum catch, with the reward. The moths learn spectral cues rapidly and choose correctly after one to several rewarded visits even when trained to different colours in sequence.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s003590050353
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  • 20
    Digitale Medien
    Digitale Medien
    Torch-light Transect Surveys for Moths (1999)
    Springer
    Journal of insect conservation 3 (1999), S. 15-24 
    Details
    ISSN: 1572-9753
    Schlagwort(e): census ; conservation ; Lepidoptera ; population monitoring ; survey techniques
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Wissenschaftskunde und Wissenschaftsorganisation, Hochschul- und Universitätswesen, Museumswissenschaft
    Notizen: Abstract The use of light traps in sampling moth populations is an established technique used by entomologists and ecologists. However, trap data partly reflect the variable attractiveness of UV light to different species of moth. There are also potential problems of the practicality and expense of running traps in certain locations. An alternative method of recording moth populations is developed, using a modification of the transect count technique used for butterflies (Pollard and Yates, 1993) and recently applied to moths (Spalding, 1997). During transects, moths were observed by torch-light in a 5 by 5 m box, before the recorder walked on for 10 paces, and recorded moths in the next 5 m box. The transect approach was tested in the field, alongside traditional light trap and sugar methods. Transects recorded moth species for relatively little effort, produced repeatable measures of relative density, and provided habitat-specific data. This approach is likely to provide a valuable addition to light trapping in biodiversity inventories, species surveys, and in monitoring the effects of habitat management for conservation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009674321237
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  • 21
    Digitale Medien
    Digitale Medien
    Bias in Butterfly Distribution Maps: The Effects of Sampling Effort (1999)
    Springer
    Journal of insect conservation 3 (1999), S. 33-42 
    Details
    ISSN: 1572-9753
    Schlagwort(e): mapping ; database ; bias recording ; monitoring ; Lepidoptera
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Wissenschaftskunde und Wissenschaftsorganisation, Hochschul- und Universitätswesen, Museumswissenschaft
    Notizen: Abstract Data from the Greater Manchester Butterfly Atlas (UK) reveal a highly significant and substantial impact of visits on both species' richness and species' incidence in squares. This effect has been demonstrated for three different zones mapped at different scales. The significant impact of number of visits persists when data are amalgamated for coarser scales. The findings demonstrate that it is essential for distribution mapping projects to record data on recording effort as well as on the target organisms. Suggestions are made as to how distribution mapping may be improved, including a geographically and environmentally representative structure of permanently monitored squares and closer links between distribution mapping and the Butterfly Monitoring Scheme (BMS), which primarily monitors changes in butterfly populations. The benefit to conservation will be data that can be better used to analyse the reasons for changes in ranges and distributions, fundamental for determining priorities and policy decisions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009678422145
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  • 22
    Digitale Medien
    Digitale Medien
    Taxonomy and the Personal Equation: The Historical Fates of Charles Girard and Louis Agassiz (1999)
    Springer
    Journal of the history of biology 32 (1999), S. 509-555 
    Details
    ISSN: 1573-0387
    Schlagwort(e): Louis Agassiz ; Spencer Baird ; Charles Girard ; reputation ; taxonomy ; ichthyology ; Museum of Comparative Zoology ; Smithsonian Institution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Geschichte
    Notizen: Abstract The reputations of scientists among their contemporaries depend not only on accomplishment, but also on interactions affected by influence and personality. The historical lore of most fields of scientific endeavor preserve these reputations, often through the identification of founders, innovators, and prolific workers whose contributions are considered fundamental to progress in the field. Historians frequently rely on the historical lore of scientists to guide their studies of the development of ideas, exhibiting justifiable caution in reassessing reputations in the light of current knowledge. However, the transmission of historical lore can obscure the relative importance of accomplishment, influence and personality in shaping contemporary reputations, leaving the historian to either accept reputations at face value or attempt to reconstruct the context in which they were created. The science of taxonomy, because of its rules of priority, leaves a relatively accurate record of historical accomplishment through the persistence of taxa in catalogues and faunal guides. These records allow the modern historian an unbiased means to assess the relative accomplishments of historical figures and therefore a means to critically reassess reputations independent of personality and influence. In the historical lore of North American ichthyology, Louis Agassiz at Harvard and Spencer Baird at the Smithsonian emerge as central figures in the early development of the field during the mid-1800s, contributing not only through the quality and quantity of their science, but also through their roles as institutional leaders and mentors to workers who followed. Charles Girard, originally a student of Agassiz's and later a coworker with Baird, receives little notice in the history of ichthyology, and his reputation is that of a minor player in the initial description of the North American fish fauna, and one whose work appears to have been flawed or even careless when compared to his contemporaries. However, a review of both contemporary and modern taxonomic works reveals that Girard's productivity far exceeded that of either Agassiz or Baird. Furthermore, an examination of the tendency of Girard and his contemporaries to introduce synonymous names into the literature, which might reflect careless or uncritical work, suggests that Girard was among the more accomplished workers of hisera, including Agassiz and Baird. Girard's low ranking in the folklore of North American ichthyology, therefore, can not be attributed to discernible shortcomings in his scientific work, but rather to a public and private campaign of criticism waged by Agassiz after Girard's departure from Harvard. While Agassiz's dispute with Girard stemmed from their personal interactions, he expressed them as criticisms of Girard's work, and thus helped shape Girard's scientific reputation as it has been transmitted through the lore of ichthyology. This case study reveals how scientific reputation may not always rest on accomplishment, but can be influenced by personal interactions obscured by time but nonetheless important to history.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1004784904703
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  • 23
    Digitale Medien
    Digitale Medien
    Larva-adult relationships in an ancestral dipteran: A re-examination of sensillar pathways across the antenna and leg anlagen of Chaoborus crystallinus (DeGeer, 1776; Chaoboridae) (1999)
    Springer
    Development genes and evolution 209 (1999), S. 103-112 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Key words Imaginal disc ; Axonal trajectories ; Ultrastructure ; Chaoborus (Insecta ; Diptera)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract  In one of his classical studies on insect metamorphosis, Weismann compared the imaginal anlagen of the ancestral phantom midge, Chaoborus, with those of advanced brachycerans. We have expanded his findings on the relationships between larval and imaginal organs using electron microscopy and cobalt backfilling of the antenna and leg anlagen and the axonal trajectories of corresponding larval sensilla. We show that both primordia are confluent with the larval antennae and ”leg” sensilla (an ancestral Keilin organ), respectively. These fully developed larval organs represent the distal tips of the imaginal anlagen rather than separate cell clusters. The axons of the larval antenna and leg sensilla project across the corresponding anlagen to their target neuromeres within the central nervous system (CNS). Within the discs, nerves composed of these larval axons, developing afferent fibres and efferences ascending from the CNS are found. Both the structure of the primordia and the axonal trajectories thus relate the situation found in advanced brachycerans with that seen in more ancestral insects. In addition, the larval antennae, legs, wings and even the eyes possess very similar afferent pioneer trajectories supporting the idea that the described pattern is generally used in the ontogeny of sensory systems.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004270050232
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  • 24
    Digitale Medien
    Digitale Medien
    Cambium: old challenges – new opportunities (1999)
    Springer
    Trees 13 (1999), S. 138-151 
    Details
    ISSN: 0931-1890
    Schlagwort(e): Key words Cytoskeleton ; Immunocytochemistry ; Model systems ; Populus ; Secondary vascular system
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract  Trees represent a, probably the, major component of the biosphere and have a unique place in the history of Mankind. One of their most fascinating features is the process of secondary growth which is effected principally by the secondary vascular system, the developmental continuum of secondary phloem, vascular cambium, and secondary xylem. However, for too long assumptions about the developmental biology of trees have had to be based upon studies of primary growth systems within annual, herbaceous species because study of the secondary vascular system had been largely ignored. Even when attempts are made to understand some of the most fundamental features of the secondary vascular system, such as xylogenesis, the current model system, isolated Zinnia mesophyll cells, is not entirely appropriate to the situation in the intact tree. Some deficiencies of the Zinnia system are discussed, and the advantages of the genus Populus as a model for study of the hardwood secondary vascular system are considered. Some of the new approaches which are poised to lead to significant advances in our knowledge of the cell bio-logy of the secondary vascular system of trees – spe-cifically of the cell wall, the plasmalemma, and the cytoskeleton – are discussed. The value of one of these new techniques – immunocytochemistry – is demonstrated by a consideration of recent work on the role of the cytoskeleton in the hardwood secondary vascular system.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/PL00009745
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  • 25
    Digitale Medien
    Digitale Medien
    Restructuring of Lepidoptera communities by introduced Vespula wasps in a New Zealand beech forest (1999)
    Springer
    Oecologia 119 (1999), S. 565-571 
    Details
    ISSN: 1432-1939
    Schlagwort(e): Key wordsVespula ; Lepidoptera ; Phenology ; Shared predator ; Ecological impact
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Introduced social wasps (Vespula vulgaris) reach high densities in some New Zealand beech forests, because honeydew provides an abundant high-energy food source. We manipulated wasp density to estimate an “ecological damage threshold” for large, free-living Lepidoptera larvae. There will be a continuum of ecological damage thresholds for wasp density depending on the prey species or habitat. Experimentally placed small caterpillars had a significantly higher survival rate than large caterpillars, and the survival rate of both groups decreased with increasing wasp density. Spring-occurring caterpillars have a probability of surviving of 0.90–0.95, assuming wasps are the only source of mortality. However, at the peak of the wasp season we predict caterpillars would have virtually no chance (probability of 10−78 to 10−40) of surviving to adults. Wasp abundance must be reduced by at least 88% to conserve the more vulnerable species of free-living caterpillars at wasp densities similar to those observed in our study sites. This equates to a damage threshold of 2.7 wasps per Malaise trap per day. It was exceeded for about 5 months of the year in non-poisoned sites. There are currently no biological or chemical control techniques available in New Zealand that will reduce wasp abundance below this damage threshold throughout the year. Our models show that most Lepidoptera with spring caterpillars will be able to persist, but species with caterpillars occurring in the peak wasp season will be eliminated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004420050820
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  • 26
    Digitale Medien
    Digitale Medien
    Megasporogenesis in Arabidopsis thaliana L.: an ultrastructural study (1999)
    Springer
    Sexual plant reproduction 12 (1999), S. 99-109 
    Details
    ISSN: 1432-2145
    Schlagwort(e): Key words Arabidopsis thaliana ; Megasporogenesis ; Meiosis ; Ultrastructure ; Cellular polarity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract  In this study, megasporogenesis of the plant model Arabidopsis thaliana was investigated by electron microscopy for the first time. The data described here could constitute a reference for future investigations of Arabidopsis mutants. During the beginning of meiosis the megaspore mother cell shows a polarity created by unequal distribution of organelles in the cytoplasm. Plastids accumulate in the chalazal region and long parallel saccules of endoplasmic reticulum, small vacuoles and some dictyosomes are found in the micropylar region. Plasmodesmata are abundant in the chalazal cell wall. The nucleus is almost centrally localized and contains a prominent excentric nucleolus and numerous typical synaptonemal complexes. After the second division of meiosis the four megaspores are separated by thin cell walls crossed by numerous plasmodesmata and do not show significant cellular organization. The young functional megaspore is characterized by a large nucleus and a large granular nucleolus. The cytoplasm is very electron dense due to the abundance of free ribosomes and contains the following randomly distributed organelles: mitochondria, a few short saccules of endoplasmic reticulum, dictyosomes and undifferentiated plastids. However, there is no apparent polarity, except for the distribution of some small vacuoles which are more abundant in the micropylar region of the cell. The degenerating megaspores are extremely electron dense and do not show any substructure.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004970050178
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  • 27
    Digitale Medien
    Digitale Medien
    Isolation and characterization of a Clostridium sp. with cinnamoyl esterase activity and unusual cell envelope ultrastructure (1999)
    Springer
    Archives of microbiology 172 (1999), S. 139-149 
    Details
    ISSN: 1432-072X
    Schlagwort(e): Key wordsClostridium xylanolyticum ; Cinnamic acid ; Esterase ; Lignocellulose ; Sporogenesis ; Ultrastructure ; Cell envelope
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Microorganisms that hydrolyse the ester linkages between phenolic acids and polysaccharides in plant cell walls are potential sources of enzymes for the degradation of lignocellulosic waste. An anaerobic, mesophilic, spore-forming, xylanolytic bacterium with high hydroxy cinnamic acid esterase activity was isolated from the gut of the grass-eating termite Tumilitermes pastinator. The bacterium was motile and rod-shaped, stained gram-positive, had an eight-layered cell envelope, and formed endospores. Phylogenetic analysis based on 16S rRNA indicated that the bacterium is closely related to Clostridium xylanolyticum and is grouped with polysaccharolytic strains of clostridia. A wide range of carbohydrates were fermented, and growth was stimulated by either xylan or cellobiose as substrates. The bacterium hydrolysed and then hydrogenated the hydroxy cinnamic acids (ferulic and p-coumaric acids), which are esterified to arabinoxylan in plant cell walls. Three cytoplasmic enzymes with hydroxy cinnamic acid esterase activity were identified using non-denaturing gel electrophoresis. This bacterium possesses an unusual multilayered cell envelope in which both leaflets of the cytoplasmic membrane, the peptidoglycan layer and the S layer are clearly discernible. The fate of all these components was easily followed throughout the endospore formation process. The peptidoglycan component persisted during the entire morphogenesis. It was seen to enter the septum and to pass with the engulfing membranes to surround the prespore. It eventually expanded to form the cortex, verification for the peptidoglycan origin of the cortex. Sporogenic vesicles, which are derived from the cell wall peptidoglycan, were associated with the engulfment process. Spore coat fragments appeared early, in stage II, though spore coat formation was not complete until after cortex formation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s002030050753
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  • 28
    Digitale Medien
    Digitale Medien
    Synergistic Sex Pheromone Components of White-Spotted Tussock Moth, Orgyia thyellina (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 1091-1104 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Lepidoptera ; Lymantriidae ; white-spotted tussock moth ; Orgyia thyellina ; (Z)-6-heneicosen-11-one ; (Z)-6-heneicosen-9-one ; (Z)-6,(E)-8-heneicosadien-11-one ; sex pheromone ; synergism ; quarantine insect ; international trade ; eradication ; Bacillus thuringiensis ; microbial insecticide
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract In 1996, the exotic white-spotted tussock moth (WSTM), Orgyia thyellina (Lepidoptera: Lymantriidae), was discovered in Auckland, New Zealand. Because establishment of WSTM would threaten New Zealand's orchard industry and international trade, eradication of WSTM with microbial insecticide was initiated. To monitor and complement eradication of WSTM by capture of male moths in pheromone-baited traps, pheromone components of female WSTM needed to be identified. Coupled gas chromatographic–electroantennographic detection analysis of pheromone gland extract revealed several compounds that elicited responses from male moth antennae. Mass spectra of the two most EAD-active compounds suggested, and comparative GC-MS of authentic standards confirmed, that they were (Z)-6-heneicosen-11-one (Z6–11-one) and (Z)-6-heneicosen-9-one, the latter termed here “thyellinone.” In field experiments in Japan, Z6–11-one plus thyellinone at a 100:5 ratio attracted WSTM males, whereas either ketone alone failed to attract a single male moth. Addition of further candidate pheromone components did not enhance attractiveness of the binary blend. Through the 1997–1998 summer, 45,000 commercial trap lures baited with 2000 μg of Z6–11-one and 100 μg of thyellinone were deployed in Auckland towards eradication of the residual WSTM population.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020833909739
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  • 29
    Digitale Medien
    Digitale Medien
    Mating system evolution in response to search costs in the speckled wood butterfly, Pararge aegeria (1999)
    Springer
    Behavioral ecology and sociobiology 45 (1999), S. 424-429 
    Details
    ISSN: 1432-0762
    Schlagwort(e): Key words Mate choice ; Search theory ; Costs and benefits ; Satyrinae ; Lepidoptera
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A general and intuitive prediction from models of mate preference is that when the cost of searching for mates increases, individuals should become less choosy. Here, we test this prediction by comparing the mating propensity of females in two populations of the butterfly Pararge aegeria. The populations originated from southern Sweden and Madeira and due to different adult emergence patterns throughout the year, the average density of males per female is likely to be lower on Madeira. Therefore, we expected that the cost of searching should be greater on Madeira and, consequently, that the Madeiran females should be less choosy. In line with predictions, the Madeiran females mated significantly sooner after the first interaction with males than did females from southern Sweden. This difference may reflect a weaker preference for territorial males over non-territorial patrollers in the Madeiran population, because of the greater costs of searching. The Madeiran females also showed a shorter time lag between mating and the start of oviposition. We discuss this unexpected result and propose that the same mechanism could also explain this population difference, i.e. different costs of searching for suitable host plants. Both search processes are fundamental for female reproductive success and we find it plausible that they can be generalised into the same theory of optimal search behaviour.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s002650050580
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  • 30
    Digitale Medien
    Digitale Medien
    Articular chondrocytes and synoviocytes in a co-culture system: influence on reactive oxygen species-induced cytotoxicity and lipid peroxidation (1999)
    Springer
    Cell & tissue research 296 (1999), S. 555-563 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Chondrocyte ; Synoviocyte ; Co-culture ; Proliferation ; Lipid peroxidation ; Cytotoxicity ; Ultrastructure ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract  Objective: A new co-culture system of rat articular chondrocytes and synoviocytes (HIG-82; cell line) was incubated with phorbol myristate acetate (PMA), H2O2 or a combination of Fe2+ and ascorbic acid to simulate inflammation-like radical attacks in articular joints. Methods: Chondrocytes were characterized by immunocytochemistry against collagen type II, transmission electron (TEM) and light microscopy. Lipid peroxidation was investigated by measuring thiobarbituric-acid-reactive material in the supernatants, cytotoxicity by determining release of lactate dehydrogenase and proliferation by measuring [3H]thymidine incorporation, culture protein and DNA. Results: PMA or Fe2+ and ascorbic acid induced lipid peroxidation in chondrocytes and synoviocytes that was decreased significantly in co-cultures. PMA and H2O2 dose dependently induced release of lactate dehydrogenase in chondrocytes, which was lowered in co-cultures or in previously co-cultured chondrocytes to a nearly basal level. In contrast, conditioned media of synoviocyte cultures showed no lowering effect on the radical-induced toxicity. Protection against H2O2-induced damage of cellular membranes by co-culturing was also shown by TEM. Synoviocytes released chondrocyte-stimulating growth factors spontaneously without previous interaction. Conclusion: Chondrocytes establish protective mechanisms against reactive oxygen species via an interaction with synoviocytes. Our co-culture model presents a possible way to study mechanisms of inflammation in articular joints under defined conditions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051317
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  • 31
    Digitale Medien
    Digitale Medien
    Ultrastructure and distribution dynamics of chloride cells in tilapia larvae in fresh water and sea water (1999)
    Springer
    Cell & tissue research 297 (1999), S. 119-130 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Chloride cells (mitochondria-rich cells) ; Teleost larvae ; Osmoregulation ; Immunohistochemistry ; Quantification ; Ultrastructure ; Oreochromis mossambicus (Teleostei)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract  Integumental and branchial chloride cells of tilapia larvae (Oreochromis mossambicus) were studied at the light-microscopical and ultrastructural level. Total numbers and distribution of chloride cells were quantified after immunostaining of cross sections of the entire larvae with an antibody against the α-subunit of Na+/K+-ATPase. The majority (66%) of Na+/K+-ATPase-immunoreactive (ir) cells, i.e. chloride cells, of freshwater tilapia larvae were located extrabranchially up to 48 h after hatching. Five days after hatching, the majority (80%) of chloride cells were found in the buccal cavity. Transfer of 24-h-old larvae to 20% sea water speeded up this process; 24 h after transfer (i.e. 48 h after hatching), the majority (59%) of chloride cells were located in the buccal cavity. The branchial chloride cell population of 24-h- and 120-h-old larvae consisted of immature, mature, apoptotic and necrotic chloride cells. However, relatively more immature chloride cells were observed in freshwater larvae (42–63%) than in (previously studied) freshwater adults (21%), illustrating the developmental state of the gills. After transfer to sea water, the incidence of degenerative chloride cells did not change. Furthermore, the incidence of immature cells had decreased and a new subtype of chloride cells, the ”mitochondria-poor” cells, appeared more frequently. These mitochondria-poor chloride cells were characterised by an abundant tubular system and relatively few mitochondria, which were aligned at the border or concentrated in one part of the cytoplasm. Most of these cells did not contact the water. The function of their enhanced appearance after seawater transfer is unknown.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051339
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  • 32
    Digitale Medien
    Digitale Medien
    Peripheral synapses at identifiable mechanosensory neurons in the spider Cupiennius salei : synapsin-like immunoreactivity (1999)
    Springer
    Cell & tissue research 295 (1999), S. 13-19 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Mechanoreceptors ; Synaptic proteins ; Histochemistry ; Ultrastructure ; Slit sensilla ; Hair sensilla ; Cupiennius salei (Chelicerata)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract Indirect immunocytochemical tests were used at the light- and electron-microscopic levels to investigate peripheral chemical synapses in identified sensory neurons of two types of cuticular mechanosensors in the spider Cupiennius salei Keys.: (1) in the lyriform slit-sense organ VS-3 (comprising 7–8 cuticular slits, each innervated by 2 bipolar sensory neurons) and (2) in tactile hair sensilla (each supplied with 3 bipolar sensory cells). All these neurons are mechanosensitive. Application of a monoclonal antibody against Drosophila synapsin revealed clear punctate immunofluorescence in whole-mount preparations of both mechanoreceptor types. The size and overall distribution of immunoreactive puncta suggested that these were labeled presynaptic sites. Immunofluorescent puncta were 0.5–6.8 μm long and located 0.5–6.6 μm apart from each other. They were concentrated at the initial axon segments of the sensory neurons, while the somata and the dendritic regions showed fewer puncta. Western blot analysis with the same synapsin antibody against samples of spider sensory hypodermis and against samples from the central nervous system revealed a characteristic doublet band at 72 kDa and 75 kDa, corresponding to the apparent molecular mass of synapsin in Drosophila and in mammals. Conventional transmissionelectron-microscopic staining demonstrated that numerous chemical synapses (with at least 2 vesicle types) were present at these mechanosensory neurons and their surrounding glial sheath. The distribution of these synapses corresponded to our immunofluorescence results.Ultrastructural examination of anti-synapsin-stained neurons confirmed that reaction product was associated with synaptic vesicles. We assume that the peripheral synaptic contacts originate from efferents that could exert a complex modulatory influence on mechanosensory activity.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051208
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  • 33
    Digitale Medien
    Digitale Medien
    Androgen-induced changes in Leydig cell ultrastructure and steroidogenesis in juvenile African catfish, Clarias gariepinus (1999)
    Springer
    Cell & tissue research 297 (1999), S. 291-299 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Teleost fish ; Puberty ; Testes ; Sex steroids ; Ultrastructure ; Steroidogenesis ; Clarias gariepinus (Teleostei)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract  The present report focuses on the mechanism(s) involved in the steroid-induced decrease of androgen production in immature African catfish testes that was observed in previous studies. Juvenile animals were implanted with Silastic pellets containing different 11-oxygenated androgens (11-ketotestosterone, KT; 11β- hydroxyandrostenedione, OHA; 11-ketoandrostenedione, KA), testosterone (T) or estradiol-17β (E2). Control groups received steroid-free pellets. Two weeks later, testis tissue fragments were either incubated with increasing concentrations of catfish luteinizing hormone (LH), or incubated with [3H]-pregnenolone ([3H]-P5) or [3H]-androstenedione ([3H]-A). Tissue fragments were also prepared for the quantitative assessment of Leydig cell morphology. Most of the parameters studied were not affected significantly by implantation of E2. Implantation of all androgens inhibited both the basal and the LH-stimulated androgen secretory capacity in vitro. This was associated with a reduced size of the Leydig cells and loss of half of their mitochondria. The studies on the metabolism of tritiated steroid hormones indicated that steroidogenic steps prior to 11β-hydroxylation, probably C17–20 lyase activity, were affected by all androgens. Although the effects of 11-oxygenated androgens and T on Leydig cells were mostly similar, previous work showed that only the 11-oxygenated androgens stimulated spermatogenesis, suggesting that distinct mechanisms of action are used by 11-oxygenated androgens and T. These mechanisms, however, seem to merge on the same target(s) to impair Leydig cell androgen production. Such a negative feedback mechanism may be of relevance in the context of the decline in androgen secretion per milligram testis tissue that accompanies the first wave of spermatogenesis in pubertal African catfish.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051357
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  • 34
    Digitale Medien
    Digitale Medien
    Morphology and synaptic connectivity of nitric oxide synthase-immunoreactive neurons in the guinea pig retina (1999)
    Springer
    Cell & tissue research 297 (1999), S. 397-408 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Retina ; NOS ; Immunocytochemistry ; Synaptic connectivity ; Guinea pig
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract  Immunocytochemical methods with an antiserum against neuronal nitric oxide synthase (NOS) were applied to identify the morphology and synaptic connectivity of NOS-like immunoreactive neurons in the guinea pig retina. In the present study, two types of amacrine cells were labeled with anti-NOS antisera. Type 1 cells had large somata located in the inner nuclear layer (INL) with long, sparsely branched processes ramifying mainly in stratum 3 of the inner plexiform layer (IPL). The somata of type 2 cells (smaller diameters) were located in the INL. Some displaced amacrine cells in the ganglion cell layer were labeled. The soma size of the displaced amacrine cells was similar to that of the type 2 amacrine cells. However, processes originating from type 2 amacrine cells and displaced amacrine cells stratified mainly in strata 1 and 5, respectively. Some cone bipolar cells were weakly NOS-immunoreactive. The synaptic connectivity of NOS-like immunoreactive amacrine cells was identified in the IPL by electron microscopy. NOS-labeled amacrine cell processes received synaptic input from other amacrine cell processes and bipolar cell axon terminals in all strata of the IPL. The most frequent postsynaptic targets of NOS-immunoreactive amacrine cells were other amacrine cell processes. Cone bipolar cells were postsynaptic to NOS-labeled amacrine cells in all strata of the IPL. Labeled amacrine cells synapsing onto ganglion cells were found only in sublamina b. A few synaptic contacts were observed between labeled cell processes. In the outer plexiform layer, dendrites of labeled bipolar cells made basal contact with cone pedicles or formed a synaptic triad opposed to a synaptic ribbon of cone pedicles.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051367
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  • 35
    Digitale Medien
    Digitale Medien
    Simultaneous apocrine and merocrine secretion in the rat coagulating gland (1999)
    Springer
    Cell & tissue research 295 (1999), S. 495-504 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Coagulating gland ; Apocrine secretion ; Merocrine secretion ; Immunocytochemistry ; Immunoelectron microscopy ; Scanning electron microscopy ; Rat (Wistar)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract The coagulating gland of the rat synthesizes two prevalent secretory proteins (transglutaminase and 115 K) that are discharched in a different manner, one being secreted in an apocrine fashion (transglutaminase) and the other one in a merocrine way (115 K). Differences in the intra- cellular pathway and the release of either protein were studied using immunofluorescence on semithin sections, immunoelectron microscopy of preembedding-processed chopper sections and postembedding-processed ultrathin sections of rat coagulating gland. Immunohistochemical staining using an anti-transglutaminase antibody resulted in dense labeling of the cytoplasm of secretory cells and their apical blebs, whereas the cisternae of the rough endoplasmic reticulum and the Golgi apparatus were completely unlabeled. When, on the contrary, the anti-115 K antiserum was used, dense labeling of the cisternae of the rough endoplasmic reticulum, the Golgi apparatus, and the secretory granules was seen. Intraluminal secretion was also labeled, but the secretory blebs remained unlabeled. Our findings show that, in the coagulating gland of the male rat, the two secretory proteins studied are processed in parallel, but at completely different intracellular pathways. They are released via different extrusion mechanisms. Transglutaminase is synthesized outside the endoplasmic reticulum, reaches the apical cell pole by free flow in the cytoplasm, and is released via apocrine blebs, the membranes of which appear to be derived from the apical plasma membrane. The protein 115 K, on the other hand, follows the classic route, being synthesized within the cisternae of rough endoplasmic reticulum, subsequently glycosylated in the Golgi apparatus, and released in a merocrine fashion. The mutual exclusion of the two secretory pathways and the regulation of the alternative release mechanism are still unresolved issues.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051255
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  • 36
    Digitale Medien
    Digitale Medien
    Immunoultrastructural expression of intercellular adhesion molecule-1 in endothelial cell vesiculotubular structures and vesiculovacuolar organelles in blood-brain barrier development and injury (1999)
    Springer
    Cell & tissue research 295 (1999), S. 77-88 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Cerebrovascular development and injury ; Hemangioma ; Angiogenesis ; Immunocytochemistry ; Adhesion molecules ; Conventional transmission and high-voltage electron microscopy ; Mouse (C57BL ; SJL/J) ; Human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract Blood vessels from the vasculature of mouse brains during postnatal development and from human brain tumors (hemangiomas) removed at biopsy were examined immunocytochemically by transmission electron microscopy (TEM) or high-voltage transmission electron microscopy (HVEM) to determine the expression of intercellular adhesion molecule-1 (ICAM-1). In the mouse brains, ICAM-1 was shown to be initially expressed on the luminal and abluminal endothelial cell (EC) surfaces on day 3 after birth. ICAM-1 intensity increased on the luminal EC surfaces and labeled vesiculotubular profiles (VTS, defined in the present report) between days 5 and 7. After 2 weeks and at 6 months after birth, ICAM-1 labeling was weak or absent on the luminal EC surfaces. The hemangiomas presented a strong ICAM-1 reaction product on the luminal EC surfaces of small and large blood vessels associated with the VTS, with a weaker labeling of the abluminal or adventitial aspects of larger blood vessels. TEM of vesiculovacuolar structures (VVOs) within ECs from arteries and veins also demonstrated reaction product for ICAM-1 labeling. Three-dimensional stereo-pair images in the HVEM enhanced the visualization of gold particles that were attached to the inner-delimiting membrane surfaces of EC VTS, and VVOs, respectively. These observations raise the possibility that the neonatal leukocytes and tumor cells may utilize these endothelial structures as a route across the developing and injured blood-brain barrier (BBB).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051214
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  • 37
    Digitale Medien
    Digitale Medien
    Periviscerokinin-like immunoreactivity in the nervous system of the American cockroach (1999)
    Springer
    Cell & tissue research 295 (1999), S. 159-170 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Neuropeptides ; Perisympathetic organ ; Myotropin ; Visceral muscles ; Immunocytochemistry ; Insect nervous system ; Periplaneta americana (Insecta)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract A highly specific polyclonal antiserum has been raised against periviscerokinin, the first neuropeptide isolated from the perisympathetic organs of insects (Predel et al. 1995). In this study, two different neuronal systems with periviscerokinin-like immunoreactivity were distinguished in the central nervous system of the American cockroach: (1) An intrinsic neuronal network, restricted to the head-thoracic region, was formed by intersegmental projecting neurons of the brain, suboesophageal ganglion and metathoracic ganglion. In addition, groups of local interneurons occurred in the proto- and tritocerebrum. (2) A typical neurohormonal system was stained exclusively in the abdomen; it was represented by abdominal perisympathetic organs which were supplied by three cell clusters located in each unfused abdominal ganglion. As revealed by nickel backfills, most neurons with axons entering the perisympathetic organs contained a periviscerokinin-like peptide. Immunoreactive fibres left the perisympathetic organs peripherally, innervated the hyperneural muscle and ran via the link nerves/segmental nerves to the heart and segmental vessels. All visceral muscles innervated by periviscerokinin-immunoreactive fibres were shown to be sensitive to periviscerokinin, whereas the hindgut gave no specific response to this peptide.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051222
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  • 38
    Digitale Medien
    Digitale Medien
    The distribution and ultrastructure of class II MHC-positive cells in human dental pulp (1999)
    Springer
    Cell & tissue research 295 (1999), S. 151-158 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Class II MHC-positive cells ; Human leukocyte antigen-DR ; Dental pulp ; Dendritic cells ; Macrophages ; Ultrastructure ; Human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract The distribution and ultrastructure of class II major histocompatibility complex (MHC)-positive cells were investigated in human dental pulp, employing immunohistochemistry using an anti-human leukocyte antigen (HLA)-DR-monoclonal antibody. HLA-DR-immunopositive cells, appearing spindle-like or dendritic in profile, were densely distributed throughout the dental pulp. Under the electron microscope, these cells exhibited various sizes of vesicles containing clear or opaque contents, multivesicular bodies and characteristic fine tubulovesicular structures in their cytoplasm. Some reactive cells possessed coated pits and vesicles including electron-dense materials, indicating an active endocytosis. At the periphery of the pulp tissue, the HLA-DR-immunopositive cells were predominantly situated in the subodontoblastic layer, with some located in the odontoblast layer and/or predentin and extending their cytoplasmic processes into the dentinal tubules. Cell processes of these cells occasionally made contact with several odontoblast processes in the same way as the nerve fibers in the predentin. These cells never contained the typical phagosomes frequently observed in the HLA-DR-immunoreactive macrophages in the subodontoblastic layer and the pulp core. The results suggest that the HLA-DR-immunopositive cells in the odontoblast layer and/or predentin have some regulatory function on the odontoblasts under physiological conditions, in addition to their involvement in the initial defense reaction after tooth injury.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051221
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  • 39
    Digitale Medien
    Digitale Medien
    Pigment-dispersing hormone-like immunoreactive neurons in the central nervous system of the gastropods, Helix pomatia and Lymnaea stagnalis (1999)
    Springer
    Cell & tissue research 295 (1999), S. 339-348 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Pigment-dispersing hormone ; Immunocytochemistry ; Central nervous system ; Gastropoda ; Helix pomatia ; Lymnaea stagnalis (Mollusca)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract By using an antiserum raised against a crustacean β-pigment-dispersing hormone (PDH), the distribution and chemical neuroanatomy of PDH-like immunoreactive neurons was investigated in the central nervous system of the gastropod snails, Helix pomatia and Lymnaea stagnalis. The number of immunoreactive cells in the Helix central nervous system was found to be large (700–900), whereas in Lymnaea, only a limited number (50–60) of neurons showed immunoreactivity. The immunostained neurons in Helix were characterized by rich arborizations in all central ganglia and revealed massive innervation of all peripheral nerves and the neural (connective tissue) sheath around the ganglia and peripheral nerve trunks. A small number of Helix nerve cell bodies in the viscero-parietal ganglion complex were also found to be innervated by PDH-like immunoreactive processes. Hence, a complex central and peripheral regulatory role, including neurohormonal actions, is suggested for a PDH-like substance in Helix, whereas the sites of action may be more limited in Lymnaea.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051240
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  • 40
    Digitale Medien
    Digitale Medien
    Effect of high-level oxygen exposure on the peroxidase activity and the neuromelanin-like pigment content of the nerve net in the earthworm, Lumbricus terrestris (1999)
    Springer
    Cell & tissue research 295 (1999), S. 349-354 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Neuromelanin ; Neuron ; Peroxidase ; Oxygen metabolism ; High-definition light microscopy ; Electron microscopy ; Ultrastructure ; Cytochemistry ; Substantia nigra ; Lumbricusterrestris (Annelida)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract Histochemical examination of 1-μm tissue sections from the dorsal nerve plexus of the earthworm, Lumbricus terrestris, reveals multiple brown intraneuronal granules. These granules contain material morphologically and histochemically consistent with neuromelanin. When viewed with transmission electron microscopy, these were seen as single membrane-enclosed biphasic granules with diameters of 370–730 nm. Exposure of L. terrestris to high-level environmental oxygen resulted in an increase in the number of neuromelanin-like pigment granules within the neurons of the circular muscle layer. As measured by ortho-phenylenediamine hydrochloride, the endogenous peroxidase activity of extracts from worms incubated in high-level environmental oxygen was 51% more than controls. The endogenous peroxidase activity was localized in situ with 3,3-diaminobenzidine (DAB) and was found to increase in and around the neuromelanin-like pigment-containing neurons within the circular muscle layer. These studies suggest that the nerve net of L. terrestris may serve as a model to study the role of neuromelanin production in oxidative stress and its relationship to endogenous peroxidases.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051241
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  • 41
    Digitale Medien
    Digitale Medien
    Immunohistochemical evidence of the presence of aromatase P450 in the rat hypophysis (1999)
    Springer
    Cell & tissue research 295 (1999), S. 419-423 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Hypophysis ; Aromatase ; Immunocytochemistry ; Morphometry ; Gender differences ; Rat (Sprague Dawley)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract In order to analyze whether aromatase is present in the hypophysis of adult rats, we have performed an immunohistochemical study in young adult male and female rats. Our study has revealed that the hypophysis of adult rats contains aromatase, although marked differences are found between the sexes. The hypophyses of male rats have cells immunoreactive for the enzyme, 34.40% of these hypophyseal cells showing reaction. By contrast, cells from female rats show very little reaction, only 0.84% of them being reactive. No significant differences in the percentage of immunoreactive cells between one phase and another are observed during the estrous cycle. Our results point to the immunohistochemical expression of aromatase in the hypophysis of adult rats and at the same time suggest that its expression is sex-dependent. The enzyme may therefore be involved in the regulation of adenohypophyseal cytology by androgens.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051248
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  • 42
    Digitale Medien
    Digitale Medien
    Survival of rat MCH (melanin-concentrating hormone) neurons in hypothalamus slice culture: histological, pharmacological and molecular studies (1999)
    Springer
    Cell & tissue research 297 (1999), S. 23-33 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Melanin-concentrating hormone neurons ; Lateral hypothalamic slice culture ; Immunocytochemistry ; Ultrastructure ; In situ hybridization ; Competitive RT-PCR ; Leptin assay ; Rat (Sprague Dawley)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract  Hypothalamic slices containing the lateral hypothalamic area (LHA) were prepared from 6- to 8-day-old rats and maintained in stationary culture for up to 35 days in order to analyse how well the melanin-concentrating hormone (MCH) neurons survived. As previously reported for other brain areas, this method yielded a long-term well-preserved organotypic organization. Light- and electron-microscopic investigations showed that differentiation continued and that synaptic contacts developed in vitro. After a period of elimination of damaged cells and fibres, most of the remaining neurons and glial cells retained a normal morphology throughout the culture period. MCH neurons, in particular, survived well as attested by the strong immunocytochemical and in situ hybridization signals still observed after several weeks. In a comparison with the day of explantation, competitive reverse transcription/polymerase chain reaction demonstrated the remarkable stability of the level of MCH mRNA at least until the 20th day in culture; after 30 days, the clear decrease in this level seemed to be correlated with a loss of MCH neurons, rather than with a decrease in MCH expression. After 10 days of culture, the incubation of slices in the presence of the hormone leptin (50 ng/ml) resulted in a strong decrease of MCH gene expression, suggesting that MCH neurons retained their physiological properties. Thus, the LHA slice stationary culture, especially between one and three weeks (i.e. after tissue stabilization and before extensive cell loss), appears to be a suitable method for physiological and pharmacological studies of these neurons.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051330
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  • 43
    Digitale Medien
    Digitale Medien
    Caveolin and its cellular and subcellular immunolocalisation in lung alveolar epithelium: implications for alveolar epithelial type I cell function (1999)
    Springer
    Cell & tissue research 295 (1999), S. 111-120 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words Caveolin ; Caveolae ; Lung ; Alveolar epithelial type I cell ; Immunocytochemistry ; Electron microscopy ; Confocal laser scanning microscopy ; Rat (CD)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract Caveolae are flask-shaped invaginations of the plasmalemma which pinch off to form discrete vesicles within the cell cytoplasm. Biochemically, caveolae may be distinguished by the presence of a protein, caveolin, that is the principal component of filaments constituting their striated cytoplasmic coat. Squamous alveolar epithelial type I (ATI) cells, comprising approximately 95% of the surface area of lung alveolar epithelium, possess numerous plasmalemmal invaginations and cytoplasmic vesicles ultrastructurally indicative of caveolae. However, an ultrastructural appearance does not universally imply the biochemical presence of caveolin. This immunocytochemical study has utilised a novel application of confocal laser scanning and electron microscopy unequivocally to localise caveolin-1 to ATI cells. Further, cytoplasmic vesicles and flask-shaped membrane invaginations in the ATI cell were morphologically identified whose membranes were decorated with anti-caveolin-1 immunogold label. Coexistent with this, however, in both ATI and capillary endothelial cells could be seen membrane invaginations morphologically characteristic of caveolae, but which lacked associated caveolin immunogold label. This could reflect a true biochemical heterogeneity in populations of morphologically similar plasmalemmal invaginations or an antigen threshold requirement for labelling. The cuboidal alveolar epithelial type II cell (ATII) also displayed specific label for caveolin-1 but with no ultrastructural evidence for the formation of caveolae. The biochemical association of caveolin with ATI cell vesicles has broad implications for the assignment and further study of ATI cell function.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051217
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  • 44
    Digitale Medien
    Digitale Medien
    Effects of reserpine on ECL-cell ultrastructure and histamine compartmentalization in the rat stomach (1999)
    Springer
    Cell & tissue research 295 (1999), S. 131-140 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Key words ECL cells ; Gastrin ; Reserpine ; Organelles ; Ultrastructure ; Rat (Sprague-Dawley)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract The histamine-storing ECL cells in the stomach play a key role in the control of acid secretion. They contain granules, secretory vesicles and microvesicles, and sustained gastrin stimulation results in the additional formation of vacuoles and lipofuscin bodies. The cells are rich in the vesicle monoamine transporter type-2 (VMAT-2), which can be inhibited by reserpine. The present study examines the effect of reserpine on ECL-cell ultrastructure and histamine compartmentalization. Rats received reserpine and/or gastrin. Reserpine was given twice by the intraperitoneal route (25 mg/kg once daily). Gastrin-17 was given by subcutaneous infusion (5 nmol/kg/h), starting at the time of the first reserpine injection and continuing for 4 days when the rats were killed. At this stage, histamine in the oxyntic mucosa was unaffected by reserpine but elevated by gastrin. Immunocytochemical analysis (confocal microscopy) showed ECL-cell histamine in control and gastrin-treated rats to be localized in cytoplasmic organelles (e.g., secretory vesicles). After treatment with reserpine alone or reserpine+gastrin, ECL-cell histamine occurred mainly in the cytosol. Planimetric analysis (electron microscopy) of ECL cells showed reserpine to increase the number, size and volume density of the granules and to reduce the size and volume density of the secretory vesicles. Gastrin reduced the number and volume density of granules and secretory vesicles, increased the number and volume density of microvesicles and caused vacuoles and lipofuscin bodies to appear. Reserpine+gastrin increased the number, volume density and size of the granules. Reserpine prevented the effects of gastrin on secretory vesicles, vacuoles and microvesicles, but did not prevent the development of lipofuscin. Our findings are in line with the views: (1) that preformed cytosolic histamine is taken up by granules/secretory vesicles via VMAT-2, that histamine is instrumental in the transformation of granules into secretory vesicles and in their consequent enlargement and (2) that vacuoles are formed by the fusion of large secretory vesicles.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004410051219
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  • 45
    Digitale Medien
    Digitale Medien
    Mycena auricoma, a new species ofMycena sectionRadiatae from Japan, andMycena spinosissima, a new record in Japan (1999)
    Springer
    Mycoscience 40 (1999), S. 73-80 
    Details
    ISSN: 1618-2545
    Schlagwort(e): Mycena auricoma ; Mycena sect.Radiatae ; Mycena spinosissima ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Two lignicolous species ofMycena (Agaricales, Basidiomycetes) are described and illustrated from eastern, Japan:Mycena auricoma sp. nov., forming ephemeral coprinoid basidiomata and belonging to sectionRadiatae, was found on a dead fallen twig ofQuercus serrata. It appears to close to a Malaysian species,“Trogia” crinipelliformis. Mycena spinosissima in sectionSacchariferae, new to Japan, was collected from dead bark ofAphananthe aspera, a dead fallen inflorescence ofCryptomeria japonica, and a dead fallen twig ofQuercus serrata.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02465677
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  • 46
    Digitale Medien
    Digitale Medien
    Macrocyst formation in three dictyostelid species,Dictyostelium monochasioides, Polysphondylium candidum, andP. pseudo-candidum (1999)
    Springer
    Mycoscience 40 (1999), S. 359-361 
    Details
    ISSN: 1618-2545
    Schlagwort(e): cellular slime molds ; dictyostelids ; macrocyst ; mating system ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Macrocyst formation in the sexual cycle was found in three dictyostelid species:Dictyostelium monochasioides, Polysphondylium candidum, andP. pseudo-candidum. Mating tests suggested thatD. monochasioides andP. pseudocandidum were heterothallic andP. candidum was homothallic. The primary walls of macrocysts had partially or fully degenerated, while the inner walls, believed to be tertiary walls, showed an undulate structure.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02463881
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  • 47
    Digitale Medien
    Digitale Medien
    Cryptophiale sphaerospora sp. nov. occurring onJanetia synnematosa (1999)
    Springer
    Mycoscience 40 (1999), S. 189-191 
    Details
    ISSN: 1618-2545
    Schlagwort(e): bamboo fungus ; hyperparasitism ; hyphomycetes ; mycoparasites ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Cryptophiale sphaerospora sp. nov. is described and illustrated based on a single collection attached to a synnematous fungus,Janetia synnematosa, from a dead bamboo culm. It differs from other species ofCryptophiala in having spherical to subspherical conidia and a cerebroid layer of phialides. The overall morohology of this species is smaller than that of previously described species.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02464297
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  • 48
    Digitale Medien
    Digitale Medien
    Structure and function of the human oocyte-cumulus-corona cell complex before and after ovulation (1999)
    Springer
    Protoplasma 206 (1999), S. 270-277 
    Details
    ISSN: 1615-6102
    Schlagwort(e): Cumulus oophorus ; Ovarian follicle ; Fertilization ; Ultrastructure ; Immunocytochemistry ; Human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The fine structure of the human cumulus oophorus has been reviewed on the basis of scanning and transmission electron microscopic observations as well as of immunofluorescence data. Tissues sampled from preovulatory ovarian follicles and cumulus-enclosed oocytes and fertilized eggs (collected from the oviduct or obtained during in vitro fertilization procedures) have been evaluated from a microtopographic and morphodynamic point of view in order to better clarify the possible role of this population of cells. In particular, the following aspects have been studied and discussed: the presence of multiple close contacts (modulated by the interposition of the zona pellucida) between the oocyte surface and the long microvillous evaginations projecting from the inner aspect of corona cells surface (through these structures the intraovarian cumulus oophorus may control oocyte growth and metabolism up until the time of ovulation); the occurrence of different subpopulations of cells (steroid-synthetic cells, cells producing adhesive proteins, leukocytes, macrophages) in the postovulatory, extraovarian cumulus oophorus surrounding oocytes, zygotes and early developing embryos. All these elements found in the cumulus mass may positively act, through their paracrine activities, on the chemical composition of the microenvironment in which fertilization occurs.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01288215
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  • 49
    Digitale Medien
    Digitale Medien
    Interface between haustoria of parasitic members of the Scrophulariaceae and their hosts: A histochemical and immunocytochemical approach (1999)
    Springer
    Protoplasma 207 (1999), S. 84-97 
    Details
    ISSN: 1615-6102
    Schlagwort(e): Haustorium ; Immunocytochemistry ; Interface ; Parasitism ; Defense mechanisms ; Scrophulariaceae
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The haustorial structure of three African parasitic members of the family Scrophulariaceae (Buchnera hispida, Rhamphicarpa fistulosa, andStriga hermonthica) has been studied with regard to the interface between haustoria and the invaded host roots. Immunocytochemical observations at the light and electron microscopical level were carried out with monoclonal antibodies against pectin. JIM5, JIM7, and hydroxyproline-rich glycoprotein (HRGP), LM1. Lignins have been visualized by phloroglucinolhydrochloric acid staining. At the margin of the lateral interface (contact area of host root cortex and parasite cells), JIM5- and JIM7-labelled substances accumulate between parasite papillae and the host root surface indicating that pectins are implicated in sealing the parasite to the attacked host organ. The lateral interface is characterized by the presence of compressed, necrotic host cells, whereas the central interface (contact area between host stele and parasite cells) is generally devoid of host cell remnants. Phenolic substances and/or lignins can be found at the site of penetration of the haustorium into the host root. These observations and the fact that HRGPs accumulate at the host side of the interface support the view of, at least, a partial defense reaction in the invaded host root tissues. Within haustoria, HRGPs were restricted to differentiating xylem elements, implying a spatio-temporal regulation of HRGPs in developmental processes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01294716
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  • 50
    Digitale Medien
    Digitale Medien
    Ultrastructural study of the relationship between generative and vegetative cells inMagnolia ×soulangeana Soul.-Bod. pollen grains (1999)
    Springer
    Protoplasma 206 (1999), S. 87-96 
    Details
    ISSN: 1615-6102
    Schlagwort(e): Plasmalemmic cord ; Pollen grain ; Ultrastructure ; Magnolia ×soulangeana
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary InMagnolia ×soulangeana pollen grains the generative cell (GC) does not become totally free within the vegetative cell (VC), at least until the pollen tube emergence. Due to a deviation in its detachment process from the sporoderm, the opposing ends of the VC plasmalemma do not fuse themselves when the GC moves away from the intine. Consequently, the interplasmalemmic space surrounding the GC does not become isolated but rather maintains continuity with the sporoderm through a complex formation that we have called plasmalemmic cord. The real existence of this formation was confirmed through serial sectioning showing the plasmalemmic cord to consist of the VC plasmalemma. In its initial portion it is occupied by a reasonably accentuated wall ingrowth of the inner layer of the intine (intine 3). In the remainder portion, neither of the cytochemical tests used in this work have revealed the presence of a significant amount of wall material. However, ultrathin sections of samples processed either chemically or by cryofixation showed the existence of an intricate system of tubules and vesicles, some of which are evaginations of the VC plasmalemma. The hypothesis that the plasmalemmic cord may have a role in the complex interactions between the two pollen cells is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01279255
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  • 51
    Digitale Medien
    Digitale Medien
    Anatomical and ultrastructural changes of the floral nectary ofPisum sativum L. during flower development (1999)
    Springer
    Protoplasma 206 (1999), S. 57-72 
    Details
    ISSN: 1615-6102
    Schlagwort(e): Anatomy ; Floral nectary ; Modified stomata ; Phloem ; Pisum sativum ; Stereology ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The floral nectary ofPisum sativum L. is situated on the receptacle at the base of the gynoecium. The gland receives phloem alone which departed the vascular bundles supplying the staminal column. Throughout the nectary, only the companion cells of the phloem exhibited wall ingrowths typical of transfer cells. Modified stomata on the nectary surface served as exits for nectar, but stomatal pores developed well before the commencement of secretion. Furthermore, stomatal pores on the nectary usually closed by occlusion, not by guard-cell movements. Pore occlusion was detected most frequently in post-secretory and secretory glands, and less commonly in pre-secretory nectaries. A quantitative stereological study revealed few changes in nectary fine structure between buds, flowers secreting nectar, and post-secretory flowers. Dissolution of abundant starch grains in plastids of subepidermal secretory cells when secretion commenced suggests that starch is a precursor of nectar carbohydrate production. Throughout nectary development, mitochondria were consistently the most plentiful organelle in both epidermal and subepidermal cells, and in addition to the relative paucity of dictyosomes, endoplasmic reticulum, and their associated vesicles, the evidence suggests that floral nectar secretion inP. sativum is an energy-requiring (eccrine) process, rather that granulocrine.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01279253
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  • 52
    Digitale Medien
    Digitale Medien
    Reproductive biology ofCaesalpinia calycina andC. pluviosa (Leguminosae) of the caatinga of north-eastern Brazil (1999)
    Springer
    Plant systematics and evolution 217 (1999), S. 43-53 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Leguminosae ; Caesalpinia ; Angiosperms ; bee-pollination ; andromonoecy ; late-acting self-incompatibility ; fruiting success
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The pollination biology, breeding system and fruiting success ofCaesalpinia calycina andC. pluviosa var.sanfranciscana were studied in caatinga vegetation in Bahia, NE Brazil. The principal pollinators for both species were carpenter bees.Caesalpinia calycina is andromonoecious but inC. pluviosa all flowers are hermaphrodite. InC. calycina all selfed flowers were abscised within 72 h despite rapid self-pollen tube growth to the ovary and ovule penetration. Prevention of selfing therefore seems to be controlled by a post-zygotic mechanism. Both species had very low fruit-set and it is suggested that this is at least in part due to geitonogamous pollinations with ovule penetration by self pollen tubes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00984921
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  • 53
    Digitale Medien
    Digitale Medien
    A molecular phylogeny of bryophytes based on nucleotide sequences of the mitochondrialnad5 gene (1999)
    Springer
    Plant systematics and evolution 218 (1999), S. 179-192 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Bryophyta ; Mitochondria ; nad5 gene ; group I intron ; molecular phylogeny ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract In contrast to animals, the slowly evolving mitochondrial nucleotide sequences of plants appear well suited to investigate phylogenetic relations between old taxonomic groups. Analysis ofnad5 gene sequences in 47 bryophytes, the living representatives of very early land plants, confirm this assessment. Statistically reliable phylogenetic trees are obtained with different mathematical approaches. A group I intron sequence conserved in thenad5 gene of all 30 mosses and 15 liverworts investigated supports a sister group relationship of the two classes. The intron sequence adds phylogenetic information for fine resolution on top of the conserved exon sequences down to the level of classically defined orders or families, respectively. This intron is not present in the hornwortsAnthoceros husnotii andA. punctatus. The results allow statements on diverging taxonomic interpretations and support the monophyly of the liverworts, mosses, Jungermanniidae, Marchantiidae and Bryidae, and allow recognition of subclasses like Hypnanae and Dicrananae. Among the mosses, the derived orders (subclass Bryidae) are confidently set apart from the Sphagnales, Andreaeales, Polytrichales and Tetraphidales with Buxbaumiales occupying a mediating position. Among the liverworts, full support is found for the classic separation of simple (jungermanniid) and complex thalloid (marchantiid) species with a strikingly low mitochondrial sequence divergence among the latter.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01089226
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  • 54
    Digitale Medien
    Digitale Medien
    An evaluation of characters obtained from life history studies for distinguishing New Zealand Porphyra species (1999)
    Springer
    Journal of applied phycology 11 (1999), S. 411-419 
    Details
    ISSN: 1573-5176
    Schlagwort(e): Bangiales ; Porphyra life history ; culture ; conchocelis ; conchosporangia ; spores ; neutral conchospores morphology ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Since 1992, as part of a study to circumscribe the genus Porphyra in New Zealand, an extensive culture programme has been developed at the Museum of New Zealand Te Papa Tongarewa. This collection currently houses more than 800 cultures and 150strains. We currently recognise at least 20 species in New Zealand, most of which are undescribed. Close observation of reproduction and the development of conchocelis-phase filaments grown in the laboratory, under controlled conditions of temperature, irradiance and photoperiod, has enabled the recognition of characters that can assist in species separation. The comparative taxonomic value of a range of such characters is discussed, including reporting a novel reproductive mode.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008175226816
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  • 55
    Digitale Medien
    Digitale Medien
    Distribution and population dynamics of Porphyra (Bangiales, Rhodophyta) in the southern Western Cape, South Africa (1999)
    Springer
    Journal of applied phycology 11 (1999), S. 429-436 
    Details
    ISSN: 1573-5176
    Schlagwort(e): distribution ; harvesting ; Porphyra ; recruitment ; seasonality ; South Africa ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Although Porphyra is commercially farmed in many countries, in South Africa only small harvests of wild populations for sale as nori have been carried out. The discovery that Porphyra improves growth of South African abalone (Haliotis midae) farmed inland-based tanks has led to increased pressure to harvest wild populations. This paper reports on a survey of the distribution and seasonality of Porphyra in the southern Western Cape. Porphyrawas present at all sites surveyed, and showed considerable temporal variation. A significant amount of the Porphyra present is in reserves and therefore protected from harvesting. Close rexamination of one site revealed seasonal populations of Porphyra that occupied different niches dependent on season. Recruitment peaked in spring and autumn, leading to dense summer and winter populations. Summer populations generally grew lower in the eulittoral than winter populations. No pattern in the mortality of larger thalli wasde tected, though sporeling mortality was high following recruitment peaks. Although it seems that most sites in the southern Western Cape are suitable for harvesting, the taxonomy of the genus in the region urgently needs revision if populations are to be appropriately managed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008173321969
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  • 56
    Digitale Medien
    Digitale Medien
    The generaAniptodera, Halosarpheia, Nais andPhaeonectriella from freshwater habitats (1999)
    Springer
    Mycoscience 40 (1999), S. 165-183 
    Details
    ISSN: 1618-2545
    Schlagwort(e): freshwater fungi ; Halosphaeriaceae ; taxonomy ; tropics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The generic concepts inAniptodera, Halosarpheia, Nais andPhaeonectriella are discussed and those species occurring in freshwater are described, some with illustrations. Five new species:Aniptodera lignicola, A. mauritaniensis, A. megalospora, A. palmicola, Phaeonectriella appendiculata are also described. A key to the freshwater species in the above genera and a synoptic diagram of their ascospores are provided.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02464295
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  • 57
    Digitale Medien
    Digitale Medien
    Dactylospora mangrovei sp. nov. (Discomycetes, ascomycota) from mangrove wood (1999)
    Springer
    Mycoscience 40 (1999), S. 317-320 
    Details
    ISSN: 1618-2545
    Schlagwort(e): Ascomycota ; marine fungi ; new species ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A new speciesDactylospora mangrovei is described and illustrated and compared withD. haliotrepha andD. canariensis, all marine inhabiting species.Dactylospora haliotrepha andD. mangrovei are tropical/sub-tropical mangrove species collected in Hong Kong, Malaysia, Taiwan and Thailand, whileD. canariensis was described from temperate waters. A map of the geographical distribution of the three marineDactylospora species is presented.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02463875
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  • 58
    Digitale Medien
    Digitale Medien
    Arecophila bambusae sp. nov. andA. coronata comb. nov., from dead culms of bamboo (1999)
    Springer
    Mycoscience 40 (1999), S. 185-188 
    Details
    ISSN: 1618-2545
    Schlagwort(e): Amphisphaeria ; ascomycetes ; bamboo fungi ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A new species ofArecophila and a species previously known asAmphisphaeria coronata are described and illustrated from dead culms of bamboo.Arecophila bambusae sp. nov. is distinct in the genus in having ellipsoidal ascospores with slightly round ends, and asci with a narrow subapical ring.Arecophila coronata comb. nov. has asci with a wedgeshaped apical ring and weakly striated ascospores enclosed in wide mucilaginous sheath.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02464296
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  • 59
    Digitale Medien
    Digitale Medien
    Concanavalin A inhibits development of tomato moth (Lacanobia oleracea) and peach-potato aphid (Myzus persicae) when expressed in transgenic potato plants (1999)
    Springer
    Molecular breeding 5 (1999), S. 153-165 
    Details
    ISSN: 1572-9788
    Schlagwort(e): lectins ; insect resistance ; transgenic plants ; potato (Solanum tuberosum) ; Lepidoptera ; Homoptera
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract The effects of concanavalin A (ConA), a glucose/mannose-specific lectin from jackbean (Canavalia ensiformis), on insect crop pests from two different orders, Lepidoptera and Homoptera, were investigated. When fed to larvae of tomato moth (Lacanobia oleracea) at a range of concentrations (0.02–2.0% of total protein) in artificial diet, ConA decreased survival, with up to 90% mortality observed at the highest dose level, and retarded development, but had only a small effect on larval weight. When fed to peach-potato aphids (Myzus persicae) at a range of concentrations (1–9μM) in liquid artificial diet, ConA reduced aphid size by up to 30%, retarded development to maturity, and reduced fecundity (production of offspring) by 〉35%, but had little effect on survival. With both insects, there was a poor correlation between lectin dose and the quantitative effect. Constitutive expression of ConA in transgenic potatoes driven by the CaMV 35S promoter resulted in the protein accumulating to levels lower than predicted, possibly due to potato not being able to adequately reproduce the post-translational processing of this lectin which occurs in jackbean. However, the expressed lectin was functionally active as a haemagglutinin. Bioassay of L. oleracea larvae on ConA-expressing potato plants showed that the lectin retarded larval development, and decreased larval weights by 〉45%, but had no significant effect on survival. It also decreased consumption of plant tissue by the larvae. In agreement with the diet bioassay results, ConA-expressing potatoes decreased the fecundity of M. persicae by up to 45%. ConA thus has potential as a protective agent against insect pests in transgenic crops.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009681705481
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  • 60
    Digitale Medien
    Digitale Medien
    System Thoughts in Manufacturing (1999)
    Springer
    Journal of systems integration 9 (1999), S. 167-185 
    Details
    ISSN: 1573-8787
    Schlagwort(e): flexibility ; complexity ; systems approach ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Notizen: Abstract In this paper we present a taxonomy of manufacturing problems, labeled in a general sense as Design, Production, or Distribution problems. One or more basic systems concepts, such as complexity and adaptation, attach themselves to each such problems. By combining the hierarchical Design—Production—Distribution idea with system concepts, we establish the fact that there is, indeed, a significant systems component to most problems of modern manufacturing.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008422627181
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  • 61
    Digitale Medien
    Digitale Medien
    Pollen morphology ofSonchus and related genera, and a general discussion (1999)
    Springer
    Plant systematics and evolution 214 (1999), S. 91-102 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Asteraceae ; Lactuceae ; Aetheorhiza ; Launaea ; Reichardia ; Sonchus ; Pollen ; taxonomy ; harmomegathy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The pollen morphology of the taxa belonging to the generaAetheorhiza Cass.,Launaea Cass.,Reichardia Roth andSonchus L. in the Iberian Peninsula has been studied with light and electron microscopy. The pollen is 3(-4)-zonocolporate and echinolophate (without polar lacunae, but in general with prelacunae), with equatorial ridges and 15–20 lacunae: 3–4 poral, 6–8 abporal and 6–8 paraporal. Small to medium size, P × E = 19−36 × 23–42 µm; sometimes two different sizes have been found. Exine 3–9 µm thick and ornamentation microreticulate and echinate. The results clearly show the relationships between genera.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00985733
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  • 62
    Digitale Medien
    Digitale Medien
    Magnoliid reproductive organs from the Cenomanian-Turonian of north-western Kazakhstan:Magnoliaceae andIlliciaceae (1999)
    Springer
    Plant systematics and evolution 216 (1999), S. 265-288 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Illiciaceae ; Illiciospermum ; Liriodendroidea ; Magnoliaceae ; Angiosperms ; Cretaceous ; fossil seeds ; Kazakhstan
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Cenomanian-Turonian sediments from the Sarbay locality in north-western Kazakhstan have yielded a rich assemblage of plant fossils including well preserved flowers, fruits, and seeds of angiosperms. This work describes fossil seeds assigned to theMagnoliaceae and theIlliciaceae. Three new species of the extinct magnoliaceous genusLiriodendroidea, L. asiatica, L. costata, andL. tenuitesta, are established and new information on the previously described species,L. alata, is provided. TheLiriodendroidea seeds are closely similar to seeds of extantLiriodendron, but are distinguished in being much smaller and winged. A new genus and species,Illiciospermum pusillum, is established based on seeds with close similarity to those of the extant genusIllicium. The seeds are small, anatropous and exotestal with outer epidermis of testa forming a palisade layer. The facets of the palisade cells have deeply undulate anticlinal walls. The micropyle area is seen on the outer integument as a transverse slit placed on a raised strophiole-like structure close to the hilum. TheIlliciospermum seeds represent the first unequivocal record of theIlliciaceae in the Cretaceous. Another seed of possible illiciaceous affinity is described as aff.Illiciospermum sp.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01084403
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  • 63
    Digitale Medien
    Digitale Medien
    Therps16 intron and the phylogeny of theRubioideae (Rubiaceae) (1999)
    Springer
    Plant systematics and evolution 214 (1999), S. 161-186 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Rubiaceae ; Rubioideae ; Angiosperms ; cladistics ; DNA sequences ; phylogeny ; rps16 intron ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The phylogeny of the subfamilyRubioideae (Rubiaceae) was estimated from sequence variation in therps16 intron (cpDNA) in 143 ingroup and 5 outgroup taxa. The analysis largely confirms a recent one based onrbcL sequences, but branch support is often much stronger. Three of the traditional subfamilies are supported,Rubioideae, Cinchonoideae s. str., andIxoroideae s. l. while there is no support forAntirheoideae. TheRubioideae are the sister group of all otherRubiaceae and comprise the tribesAnthospermeae, Coccocypseleae, Cruckshanksieae, Coussareeae, Gaertnereae, Hedyotideae, Knoxieae, Morindeae, Ophiorrhizeae, Paederieae, Pauridiantheae, Perameae, Psychotrieae, Rubieae, Spermacoceae, Theligoneae, andUrophylleae. TheHamelieae andHillieae belong to theCinchonoideae. Rachicallis andSiemensia should be transferred from theHedyotideae to theCinchonoideae. ThePauridiantheae, Urophylleae, Ophiorrhizeae, andRaritebe form the basalmost subclade of theRubioideae. The second basalmost clade consists of the generaLasianthus andPerama. The third basalmost clade consists of the tribesCoussareeae, Coccocypseleae andCruckshanksieae, and the generaDeclieuxia andHindsia. The tribesKnoxieae, Anthospermeae, Argostemmateae, Paederieae, Theligoneae, Rubieae, Hedyotideae, andSpermacoceae are members of one clade. TheKnoxieae are monophyletic ifOtiophora, Otomeria, andPentas are included. The tribeAnthospermeae is supported as monophyletic, but its subtribes are not. ThePaederieae, together withTheligonum, form a paraphyletic grade basal to theRubieae. TheHedyotideae, includingSchismatoclada, form a grade at the base of theSpermacoceae. TheGaertnereae are monophyletic and distinct from thePsychotrieae. TheMorindeae are monophyletic and includeDamnacanthus andMitchella. Schradera is the sister group of theMorindeae. ThePsychotrieae are monophyletic when theGaertnereae, Lasianthus, andDeclieuxia are excluded. The recognition of a subtribeHydnophytineae leaves the rest of thePsychotrieae paraphyletic.Psychotria is paraphyletic with respect to all other genera of the tribe. Approximately 50 genera are here classified for the first time based on molecular data.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00985737
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  • 64
    Digitale Medien
    Digitale Medien
    Genome characterization and relationships between two species of the genusLobelia (Campanulaceae) determined by repeated DNA sequences (1999)
    Springer
    Plant systematics and evolution 214 (1999), S. 211-218 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Campanulaceae ; Lobelia ; Angiosperms ; in situ hybridization ; karyotype evolution ; rDNA ; telomere
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Three repeated DNA sequences (rDNA 5S, 18S-5.8S-26S and telomeric repeats) were localised in the genomes ofLobelia brasiliensis andL. imperialis var.kanitzii (subg.Tupa), both with 2n = 28, by fluorescence in situ hybridization (FISH). The results were used to analyse the genomic relationship between the species. With probe pTa71, the karyotypes of these species showed only one NOR site. Probe pTa794, which contains 5S rDNA, demonstrated differences between the species. Telomeric sequences, studied with probe pLT11, were not detected in ectopic sites, but different telomeres showed signals of varying intensity. Based on the results obtained, considerations are made on karyotype evolution inLobelia.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00985740
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  • 65
    Digitale Medien
    Digitale Medien
    DNA sequence data reveal polyphyly of Brexioideae (Brexiaceae; Saxifragaceae sensu lato) (1999)
    Springer
    Plant systematics and evolution 219 (1999), S. 199-208 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Brexioideae ; Brexia ; Ixerba ; Roussea ; Saxifragaceae s. l. ; 18S rDNA andrbcL sequence analysis ; molecular systematics ; phylogenetic analysis ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Previous molecular phylogenetic analyses have demonstrated that Saxifragaceae sensu lato are polyphyletic, with component lineages scattered throughout the eudicots. As part of our effort to elucidate the relationships of members of Engler and Prantl's Saxifragaceae s. l., we undertook a molecular systematic study of subfamily Brexioideae, which comprises three genera:Brexia, Ixerba, andRoussea. Not all taxonomic treatments have concurred, however, in placing these genera together. To elucidate relationships among these three genera as well as their relationships to other angiosperms we constructed large data sets ofrbcL, 18S rDNA, andrbcL + 18S rDNA sequences. Our phylogenetic analyses indicate clearly that Brexioideae are polyphyletic.Brexia is part of a celastroid clade that also includesParnassia, Lepuropetalon, and Celastraceae.Ixerba appears as sister to a large eurosid I clade;Roussea appears as part of Asterales. Molecular data, therefore, indicate that Brexioideae are a polyphyletic assemblage and component genera should ultimately be incorporated into other groups. Our studies continue to demonstrate the polyphyly not only Saxifragaceae s. l., but also of its constituent subfamilies.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00985579
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  • 66
    Digitale Medien
    Digitale Medien
    Immunolocalization of the cell wall components inPinus densiflora pollen (1999)
    Springer
    Protoplasma 206 (1999), S. 1-10 
    Details
    ISSN: 1615-6102
    Schlagwort(e): Arabinogalactan protein ; Cell wall component ; Immunocytochemistry ; Pectin ; Pinus densiflora ; Pollen
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary In order to compare cell wall formation in gymnosperm pollen with that in angiosperm pollen, the distribution of cell wall constituents in the pollen grain and pollen tube ofPinus densiflora was studied immunocytochemically with monoclonal antibodies JIM 5 (against non- or poorly esterified pectin), JIM 7 (against highly esterified pectin), JIM 13 (against arabinogalactan proteins, AGPs), and LM 2 (against AGPs containing glucuronic acid). In the pollen grain wall, only the outer layer of the intine was labeled with JIM 5 and weakly with JIM 7. The tube wall was scarcely labeled with JIM 5 and very weakly labeled with JIM 7. In contrast, the whole of both the intine and the tube wall was strongly labeled with JIM 13 and LM 2, and the generative-cell wall was also labeled only with LM 2. The hemicellulose B fraction, which is the main polysaccharide fraction from the pollen tube wall, reacted strongly with JIM 13 and especially LM 2, but not with antipectin antibodies. These results demonstrate that the wall constituents and their localization inP. densiflora pollen are considerably different from those reported in angiosperm pollen and suggest that the main components of the cell wall ofP. densiflora pollen are arabinogalactan and AGPs containing glucuronic acid.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01279247
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  • 67
    Digitale Medien
    Digitale Medien
    Distribution and transmission of endosymbiotic microorganisms in the oocytes of the pig louse,Haematopinus suis (L.) (Insecta: Phthiraptera) (1999)
    Springer
    Protoplasma 209 (1999), S. 207-213 
    Details
    ISSN: 1615-6102
    Schlagwort(e): Endosymbiont ; Mycetocyte ; Mycetome ; Oocyte ; Transovarial transmission ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary All anoplurans live symbiotically with prokaryotic microorganisms hosted in specialized cells, termed mycetocytes. In nymphs and males mycetocytes are distributed between midgut epithelial cells. In females, besides the midgut, mycetocytes are found in the reproductive organs where they are located at the base of ovarioles in contact with lateral oviducts. The mycetocyte-associated symbionts are transmitted from one generation to the next transovarially. Here, the results of histological and ultrastructural studies on the distribution and transmission of symbiotic microorganisms within the ovaries of the anopluranHaematopinus suis are presented. Interestingly, during advanced oogenesis (i.e., choriogenesis) of this species all symbionts are localized extracellularly and form a tight mass located at the posterior pole of the oocyte just below the hydropyle. In insects studied so far, such localization of transovarially transmitted microorganisms has been reported only in the closely related speciesHaematopinus eurysternus.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01453449
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  • 68
    Digitale Medien
    Digitale Medien
    Immunolocalization of the petunia floral binding proteins 7 and 11 during seed development in wild-type and expression mutants ofPetunia hybrida (1999)
    Springer
    Protoplasma 208 (1999), S. 224-229 
    Details
    ISSN: 1615-6102
    Schlagwort(e): Floral binding protein ; Flower development ; Immunocytochemistry ; MADS-box genes ; Ovule ; Transcription factors
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary DuringPetunia hybrida seed development, the MADS-box genes encoding the floral binding proteins (FBP) 7 and 11 are expressed in the seed coat and not in the endosperm or embryo. These proteins are thought to function as transcription factors and are essential for ovule formation inPetunia spp. Immunocytochemical methods were used to analyze the distribution of FBP7 and FBP11 after fertilization in wild type and ectopic and cosuppression mutants. During the first nine days of seed development the protein was found in the nuclei of seed coat cells, of both wild-type plants and plants which ectopically expressedFBP11. The signal for FBP7 and -11 proteins diminished during seed development, was first lost in the outer epidermis of the seed coat, then in the endothelium, and finally, at 9 days after pollination (DAP), the protein could not be detected anymore in the parenchyma cells of the seed coat. Although the distribution patterns in wild-type andFBP11 ectopically expressing plants are similar, the latter exhibited higher protein levels. A mild-cosuppression mutant ofFBP7 andFBP11, having only a total of 5%FBP7 and -11 mRNA, showed hardly any FBP7 and -11 proteins. The lack of FBP7 and -11 caused endosperm degeneration in the mutant at a moment when the protein had already decreased to an undetectable level in the wild type and ectopic expression mutant (i.e., at 13 DAP). It is suggested that till about 9 DAP a minimal amount of FBP7 and -11 is needed for the normal functioning of the seed coat during later stages, i.e., for transfer of nutrients to endosperm and embryo. Besides the immunocytochemical data on theFBP7 andFBP11 MADS-box gene products, the morphological analysis of wild type and mutants contributes details on early seed development inPetunia hybrida.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01279093
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  • 69
    Digitale Medien
    Digitale Medien
    On the Origin of Almond (1999)
    Springer
    Genetic resources and crop evolution 46 (1999), S. 143-147 
    Details
    ISSN: 1573-5109
    Schlagwort(e): Amygdalus ; distribution ; domestication ; taxonomy ; wild relatives
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Almond, Amygdalus communis L., is an ancient crop of south west Asia. Selection of the sweet type marks the beginning of almond domestication. Wild almonds are bitter and eating even a relatively small number of nuts can be fatal. How man selected the sweet type remains a riddle. Also, the wild ancestor of almond has not been properly identified among the many wild almond species. Breeding experiment, which is the most critical test for identifying the wild progenitors of other crops, is ineffective in almond, because it is interfertile with many wild taxa. The so-called wild A. communis of central Asia cannot be regarded as a genuine wild form, but as a feral form, or remains of old afforestation. The wild taxa morphologically akin to almond, A. korshinskyi (H.-M.) Bomm. and A. webbii Spach, are also feral types occurring in the Middle East and southern Europe, respectively. The taxon A. fenzliana (Fritsch) Lipsky is the most likely wild ancestor of almond for three reasons: 1. It is a genuine wild type forming extensive thickets of large trees young seedlings and all the intergradations between them in nature; 2. Its morphology, and particularly the partially pitted grooved nut-shell are within the range of variation of almond, and 3. A. fenzliana is native of Armenia and western Azerbaijan in the Middle East where almond was apparently domesticated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008690409554
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  • 70
    Digitale Medien
    Digitale Medien
    Phylogeny of Vicia Subgenus Vicia (Fabaceae) Based on Analysis of RAPDs and RFLP of PCR-Amplified Chloroplast Genes (1999)
    Springer
    Genetic resources and crop evolution 46 (1999), S. 149-161 
    Details
    ISSN: 1573-5109
    Schlagwort(e): evolution ; genetic resources ; PCR-RFLP ; RAPDs ; Vicia ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract We report the results of two methods of DNA analysis to elucidate phylogenetic relationships among 29 Vicia subgen. Vicia species in comparison with two species of subgenus Vicilla sect. Vicilla. The methods employed were RAPD analysis of total genomic DNA and PCR-RFLP analysis of five chloroplast genes, rbcL, rpoB, 16S, psaA and trnK. The results of each method were similar and complementary, and support the current taxonomic systems of subsp. Vicia. According to RAPD and PCR-RFLP analysis the Narbonensis complex can be considered a well separated section, which may be related to section Vicia. Sections Vicia, Atossa and Wiggersia are separate, but closely related sections. Species of the section Hypechusa form a single monophyletic section, where V. lutea, V. anatolica and V. hyrcanica are quite remote from other species. Our results suggest that within the subgenus Vicia, V. faba is more closely related to V. bithynica and that these two species are most closely related to section Peregrinae. We found that PCR-RFLP of cp DNA provided more precise information concerning relationships between Vicia sections than RAPD analysis. However, RAPD analysis was more informative concerning diversity of closely related Vicia taxa, such as the variable groups, section Narbonensis and V. sativa aggregate.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008640322198
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  • 71
    Digitale Medien
    Digitale Medien
    The Vicia sativa L. aggregate (Fabaceae) in Southern Brazil (1999)
    Springer
    Genetic resources and crop evolution 46 (1999), S. 207-211 
    Details
    ISSN: 1573-5109
    Schlagwort(e): introduced species ; karyotypes ; taxonomy ; Vicia sativa agg
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract V. sativa L. sensu strictu was introduced in Rio Grande do Sul (Southern Brazil) by Italian settlers and is nowadays cultivated for forage in backyards and fields. V. angustifolia L. is a widespread highly polymorphic naturalized ruderal. Both taxa grow sympatrically and morphologically transitional types are often found. We analyzed 37 accessions of V. sativa, V. angustifolia, intermediate types, and V. cordata Wulf. ex. Hoppe from Rio Grande do Sul, for karyotypes, corolla and legume color, seed color pattern, pod constrictions and phenological development. Karyotypes allowed a clear distinction between the taxa: V. sativa (2n=12) had a metacentric marker chromosome, V. angustifolia and intermediate types (2n=12) only acrocentric chromosomes and V. cordata presented 2n=10. Flowering and fruiting periods were shorter for V. sativa than for V. angustifolia, which was separated into early and late flowering groups. Qualitative characters separated the taxa by Jaccard coefficients into three groups: V. sativa at 0.5 similarity level, V. angustifolia and intermediate types at 0.6 and V. cordata joined V. sativa at 0.12. Our results show that karyotypes and a range of qualitative characters are diagnostic for the aggregate represented in Southern Brazil.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008657615898
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  • 72
    Digitale Medien
    Digitale Medien
    Status and phylogenetic relationships of Daphnia sarsi Daday, 1902 (Crustacea: Anomopoda) (1999)
    Springer
    Hydrobiologia 403 (1999), S. 27-38 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Cladocera ; Daphnia ; taxonomy ; homonymy ; phylogenetic relationships ; Patagonia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Daphnia sarsi Daday, 1902 is redescribed from Patagonian populations and type material. Its taxonomic and nomenclatorial status is discussed. Because of the homonymy with D. sarsi Schödler, 1877, assigned to Australian populations, D. dadayana is proposed as new name. It is concluded that D. dadayana is a valid species with several morphological peculiarities and the proposed synonymies with D. carinata and D. similis can not be supported. Its subgeneric position is intermediate between Daphnia s. str. and Ctenodaphnia and there is an ontogenetical shift of the dorsocephalic suture from Ctenodaphnia-like to Daphnia-like. The possible origin of the group of species assigned to the subgenus Daphnia from a Ctenodaphnia-like ancestor is suggested.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003712715676
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  • 73
    Digitale Medien
    Digitale Medien
    Nematodes from the Strait of Magellan and the Beagle Channel (Chile): the genus Sabatieria (Comesomatidae: Nematoda) with the description of Sabatieria coomansi n. sp. (1999)
    Springer
    Hydrobiologia 405 (1999), S. 95-115 
    Details
    ISSN: 1573-5117
    Schlagwort(e): taxonomy ; marine nematodes ; Sabatieria ; the Strait of Magellan ; Chile
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Eight species of the genus Sabatieria, one of which is new to science, are described from the Strait of Magellan and the Beagle Channel, Chile. Sabatieria coomansi n. sp. is characterised by a rather long body (3236–4012 μm) with conspicuous lateral differentiation; head diameter 24 μm, amphids 2.25 turns; long spicules (132–149 μm) or 1.6–1.9 abd, 23–26 precloacal supplements, tail 3.3–3.6 abd. This species belongs to the praedatrix group (Platt, 1985). Sabatieria arcuata is found since its original description by Wieser in 1954. Six other species, i.e., S. celtica Southern, 1914, S. falcifera Wieser, 1954, S. furcillata Wieser, 1954, S. granifer Wieser, 1954, S. mortenseni (Ditlevsen, 1921) and S. parabyssalis Wieser, 1954 are redescribed in detail with emphasis on new or shortly described morphological features.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003752619953
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  • 74
    Digitale Medien
    Digitale Medien
    Redescription of Heliodiaptomus elegans Kiefer, 1935, a rare south-east Asian calanoid copepod (1999)
    Springer
    Hydrobiologia 394 (1999), S. 145-152 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Heliodiaptomus ; H. elegans ; redescription ; synonymy ; H. serratus ; taxonomy ; Copepoda ; Calanoida
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Heliodiaptomus elegans Kiefer, 1935, incompletely described from Myanmar, is redescribed on specimens from Thailand. A Chinese congener, H. serratus Shen & Tai, 1962, is sunk into the synonymy of H. elegans.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003682716375
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  • 75
    Digitale Medien
    Digitale Medien
    Taxonomy and morphology of limnic microturbellarians (Plathelminthes) in Extremadura (Spain) (1999)
    Springer
    Hydrobiologia 397 (1999), S. 21-28 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Turbellaria ; taxonomy ; morphology ; Extremadura ; Spain
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Three new species of Rhabdocoela belonging to the Families Dalyellidae: Microdalyellia bipennata, and Typhloplanidae: Mesocastrada iberiensis, and Mesostoma extremeniensis are described. Fourteen species of the Orders Catenulida, Macrostomida, Proseriata and Rhabdocoela are cited the first time for Extremadura (southwest Spain).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003565505722
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  • 76
    Digitale Medien
    Digitale Medien
    On the presence of Chirocephalus croaticus (Steuer, 1899) in an intermittent lake in SW Slovenia (1999)
    Springer
    Hydrobiologia 412 (1999), S. 25-34 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Chirocephalus ; Anostraca ; taxonomy ; ecology ; Slovenia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Numerous specimens of Chirocephaluswere found repeatedly over the last eight years in an intermittent lake in SW Slovenia. They were first identified as Chirocephalus spinicaudatusSimon, 1886. Later it turned out that they fit the diagnosis of Chirocephalus croaticus (Steuer, 1899), a species described from a small lake in Southern Croatia, about 300 km from Slovenia. It was considered as endemic of its type locality only. Now its range expands into NW direction. The population in Slovenia is in good condition and, if there is no change in land use, could persist for a long time. A small population of the same species in a small puddle near the intermittent lake Cerkniško Jezero (about 30 km from lake Petelinjsko Jezero) was destroyed a few years ago. A detailed description of specimens of both sexes is given and some information on their ecology is added. Particular attention is given to the male legs which could provide good diagnostic characters. For comparison, legs of Chirocephalus diaphanus Prévost, 1803 are shown.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003840014310
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  • 77
    Digitale Medien
    Digitale Medien
    A new species of Cletocamptus Schmankewitsch 1875 (Copepoda; Harpacticoida) from a mangrove forest in Malaysia (1999)
    Springer
    Hydrobiologia 412 (1999), S. 143-153 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Cletocamptus merbokensis ; Harpacticoida ; taxonomy ; Malaysia ; mangroves
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Cletocamptus merbokensis sp. nov. is described from material collected out of muddy sediments in the Merbok mangrove forest, northwest peninsula Malaysia. It is distinguished from all other known species of Cletocamptus by the presence of only two setae on P2 and P3 endopod-2 and no inner seta on P4 exopod-2; and by the form of the male P5 in which the baseoendopod and most of the endopodal and exopodal lobes are absorbed into the somatic cuticle. The higher taxonomic position of the genus is briefly discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003825021579
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  • 78
    Digitale Medien
    Digitale Medien
    Variation in Gillraker Number During Growth of the Sea Bass, Dicentrarchus labrax (Perciformes: Moronidae), Reared at Different Salinities (1999)
    Springer
    Environmental biology of fishes 55 (1999), S. 391-398 
    Details
    ISSN: 1573-5133
    Schlagwort(e): ecophenotypism ; branchial sieve ; geographic variation ; fish ; meristics ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A marked salinity-related decrease in gillraker number in sea bass samples during growth was documented. All specimens share the same genetic stock and rearing conditions were constant during early ontogeny. Variation in gillraker number could be related to the ecophenotypism of this character but selection can not be excluded. Results obtained from reared specimens were compared with those reported in the literature and with data collected from wild stocks. Attention is focused on the pitfalls that the use of this character may have on the taxonomy of fish species.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1007548102060
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  • 79
    Digitale Medien
    Digitale Medien
    Geographical variation in the southern distributional range of the Rufous-tailed Hummingbird,Amazilia tzacatl De la Llave, 1832: a new subspecies from Nariño, southwestern Colombia (1999)
    Springer
    Journal of ornithology 140 (1999), S. 457-466 
    Details
    ISSN: 1439-0361
    Schlagwort(e): Geographic variation ; taxonomy ; Rufous-tailed Hummingbird ; Amazilia tzacatl brehmi ; subspec. nov. ; Trochilidae
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Von der in Mittelamerika und in NW-Südamerika weitverbreiteten Braunschwanzamazilie (Amazilia tzacatl) wurden mehrere Unterarten beschrieben, von denen in der neueren Literatur drei anerkannt wurden:A. t. tzacatl (De la Llave, 1832) mit einem Vorkommen von NO-Mexiko bis W-Venezuela einschließlich N-Kolumbiens;A. t. jucunda (Heine, 1863) von W-Kolumbien bis SW-Ecuador; undA. t. handleyi (Wetmore, 1963) als Endemit der Panamá vorgelagerten Isla Escudo de Veraguas (Karibik). Letzteres Taxon wird von einigen Autoren als Allospezies angesehen, hier aber lediglich als Unterart bewertet, da offenbar nur morphometrische Unterschiede zu den übrigen Taxa bestehen. Die Ergebnisse der vorliegenden biogeographisch-taxonomischen Analyse belegen, daß die geographische Variation der Art im südlichen Verbreitungsgebiet größer ist als bislang angenommen wurde. Aufgrund signifikanter Unterschiede in den Gefiedermaßen erhält die kolumbianischvenezuelanische Population ihren früheren, eigenständigen taxonomischen Rang (A. t. fuscicaudata Fraser, 1840) zurück. Ein neues Taxon,Amazilia tzacatl brehmi subsp. nov., wird von Nariño, Südwestkolumbien, beschrieben. Diese Unterart tritt offenbar allopatrisch zuA. t. jucunda auf und unterscheidet sich morphometrisch deutlich von konspezifischen Nachbarpopulationen.
    Notizen: Summary The Rufous-tailed Hummingbird (Amazilia tzacatl De la Llave, 1832), a widespread inhabitant of Central America and NW South America, currently comprises two subspecies (A. t. tzacatl andA. t. jucunda). Another taxon of the species complex isA. t. handleyi (Wetmore, 1963), initially described as an allospecies but here regarded only as a subspecies ofA. tzacatl. Based on diverging morphological features, the amount of geographical variation ofA. tzacatl in its South American range suggests the distinction of further populations. As a taxonomical consequence, we recognize the validity ofA. t. fuscicaudata (Fraser, 1840), and describe a new subspecies,A. t. brehmi subspec. nov., from Nariño, Colombia.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01650990
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  • 80
    Digitale Medien
    Digitale Medien
    Pheromone Components and Diel Periodicity of Pheromonal Communication in Lymantria fumida (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 2305-2312 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Lepidoptera ; Lymantriidae ; Lymantria fumida ; Lymantria monacha ; nun moth ; sex pheromone ; periodicity ; calling behavior ; reproductive isolation ; disparlure ; (7R,8S)-cis-7,8-epoxy-2-methyloctadecane ; (7S,8R)-cis-7,8-epoxy-2-methyloctadecane ; 2-methyl-Z7-octadecene ; (7R,8S)-cis-7,8-epoxy-octadecane ; (+)-monachalure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Extracts of pheromone glands from female Lymantria fumida were analyzed by coupled gas chromatographic–electroantennographic detection (GC-EAD) and by coupled GC–mass spectrometry (MS). The two compounds that elicited responses from male L. fumida antennae were identified as cis-7,8-epoxy-2-methyloctadecane (disparlure) and 2-methyl-Z7-octadecene (2me-Z7–18Hy). Field experiments in northern Japan demonstrated that synthetic (7R,8S)-cis-7,8-epoxy-2-methyloctadecane [(+)-disparlure] and 2me-Z7–18Hy are synergistic sex pheromone components of L. fumida. (7S,8R)-cis-7,8-Epoxy-2-methyloctadecane [(−)-disparlure] had no behavioral effect on male L. fumida. Traps baited with (+)-disparlure and 2me-Z7–18Hy captured male L. fumida between 21:00 and 24:00 hr, whereas traps baited with (+)-monachalure [(7R,8S)-cis-7,8-epoxy-octadecane], (+)-disparlure and 2me-Z7–18Hy attracted males of the nun moth, L. monacha L., between 02:00 and 04:00 hr. Both temporal separation of pheromonal communication and specificity of pheromone blends seem to contribute to the reproductive isolation of sympatric and coseasonal L. fumida and L. monacha.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020873807864
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  • 81
    Digitale Medien
    Digitale Medien
    A Novel Bioassay for Yponomeuta cagnagellus Oviposition in Response to Extracts of Host and Nonhost Plant Surface Compounds (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 2547-2559 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Yponomeuta cagnagellus ; ermine moth ; Lepidoptera ; speciation ; specialization ; plant surface compounds ; oviposition ; host discrimination ; Euonymus europaeus
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Yponomeuta cagnagellus is a phytophagous moth species specialized on Euonymus europaeus. Host discrimination by the adult female is an important aspect of host specialization and is based mainly on the distinctive secondary chemistry of host and nonhosts. This paper describes a bioassay that was developed to study the effect of isolated plant surface compounds on Yponomeuta oviposition. Adult moths recognize their hosts through chemical stimuli on the leaf or twig surface. Relatively apolar compounds extracted from the host twig surface by washing in dichlormethane do not stimulate oviposition. More polar, methanol-soluble compounds do, and this stimulation is dose dependent. Moths are able to recognize hosts solely by their surface compounds: females show a strong preference for artificial twigs treated with methanolic extracts of their hosts compared to those treated with methanolic extracts of nonhosts Crataegus monogyna and Prunus spinosa (both of which are hosts for closely related Y. padellus). Shape and surface characteristics of the oviposition substrate also influence oviposition. The substrate needs to resemble the basic form of a twig (i.e., cylindrical), and females prefer a coarse surface with irregularities over a smooth one.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020882326462
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  • 82
    Digitale Medien
    Digitale Medien
    An Oviposition Stimulant for Spicebush Swallowtail Butterfly, Papilio troilus, from Leaves of Sassafras albidum (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 1233-1245 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Swallowtail butterfly ; Papilionidae ; Papilio troilus ; Lepidoptera ; Lauraceae ; Sassafras albidum ; oviposition stimulant ; 3-trans-caffeoyl-muco-quinic acid
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Female butterflies of the spicebush swallowtail, Papilio troilus, are specialists, ovipositing on plants in the family Lauraceae. Column chromatography and HPLC were used to isolate an oviposition stimulant from the leaves of one of its hosts, Sassafras albidum. The stimulant was identified as 3-trans-caffeoyl-muco-quinic acid on the basis of FAB-MS and 1H NMR spectra as compared to a compound previously isolated from another plant. It was not active alone, but it increased the oviposition activity of butterflies when combined with other stimulant(s) at a concentration of 7 ng/mm2 leaf surface area. Other caffeoylquinic acid isomers tested did not have this effect. This is the first report of a swallowtail contact oviposition stimulant from a plant in the family Lauraceae.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020962422712
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  • 83
    Digitale Medien
    Digitale Medien
    Behavioral Response of Female Codling Moths, Cydia pomonella, to Apple Volatiles (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 1343-1351 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Host-plant volatiles ; apple ; Malus domestica ; reproductive behavior ; codling moth ; Cydia pomonella ; Tortricidae ; Lepidoptera
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Apple volatiles stimulated pheromone release, oviposition, and upwind orientation in female codling moths, Cydia pomonella. Green apples increased the percentage of virgin females calling, the duration of female calling, and advanced the onset of egg-laying in gravid females. In a tube olfactometer, both virgin and mated females were more active in the presence of apple volatiles than in clean air. They responded by walking while wing-fanning; mated females showed a stronger attraction response than unmated females.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020978826346
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  • 84
    Digitale Medien
    Digitale Medien
    Volatile Stimuli Related to Feeding Activity of Nonprey Caterpillars, Spodoptera exigua, Affect Olfactory Response of the Predatory Mite Phytoseiulus persimilis (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 1585-1595 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Tritrophic interactions ; Lima bean ; Phytoseiulus persimilis ; Tetranychus urticae ; Spodoptera exigua ; Acari ; Lepidoptera ; infochemicals ; herbivore-induced plant volatiles ; nonprey herbivores ; feces
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The effect of volatiles related to feeding activity of nonprey caterpillars, Spodoptera exigua, on the olfactory response of the predatory mites Phytoseiulus persimilis was examined in a Y-tube olfactometer. At a low caterpillar density (20 caterpillars on 10 Lima bean leaves), the predators were significantly more attracted to volatiles from infested leaves on which the caterpillars and their products were present or from infested leaves from which the caterpillars and their products had been removed when compared to volatiles from uninfested leaves. The predators, however, significantly avoided odors from 20 caterpillars and their products (mainly feces) removed from bean leaves. In contrast, at a higher caterpillar density (100 caterpillars on 10 Lima bean leaves), the predators avoided volatiles from caterpillar-infested bean leaves. Volatiles from infested leaves from which the caterpillars and their products had been removed were not preferred over volatiles from uninfested leaves. Volatiles from feces collected from 100 caterpillars were strongly avoided by the predators, while the behavior of the predatory mites was not affected by volatiles from 100 caterpillars removed from a plant. The data show that carnivorous arthropods may avoid nonprofitable herbivores. This avoidance seems to result from an interference of volatiles from herbivore products with the attraction to herbivore-induced plant volatiles.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020888816525
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  • 85
    Digitale Medien
    Digitale Medien
    Evolution and Adaptive Significance of Larval Midgut Alkalinization in the Insect Superorder Mecopterida (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 1945-1960 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Insect–plant interaction ; midgut alkalinization ; phylogenetic distribution ; Mecopterida ; Diptera ; Lepidoptera ; Trichoptera ; polyphenolics ; alkylating agents
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The phylogenetic distribution of reported midgut pH values among larval Mecopterida supports a model in which the common ancestor of this group possessed an alkaline midgut, with subsequent loss of this trait in the lineage leading to the muscomorphan Diptera. The relationship between midgut pH and diet guild rank within the Lepidoptera and Diptera was tested by assigning numerical values to diet guilds (i.e., fruit, grasses, herbs, trees and shrubs, and organic detritus). Lepidopteran superfamilies were found to differ significantly in both midgut pH and in diet guild rank. Regression of mean superfamily midgut pH against mean superfamily diet guild rank yielded an R 2 of 0.79 (N = 10), whereas regression of species midgut pH against species diet guild rank yielded an R 2 of only 0.15 (N = 60). Species feeding on foliage of plant taxa high in tannins and on Solanaceae have midgut pH values above 9, and midgut pH in species feeding on these taxa is positively related to diet guild. In contrast, species feeding on the foliage of plant taxa containing terpenes, DIMBOA, glucosinolates, and pyrrolizidine alkaloids have midgut pH values near 8, and midgut pH of these species is either not related to diet guild (all species) or is negatively related to diet guild rank when the analysis is limited to the Noctuoidea. The data suggest that decreased midgut pH in species feeding on plants containing terpenes, DIMBOA, glucosinolates, and pyrrolizidine alkaloids may be an adaptive response that overrides selection for high pH in the presence of tannins and that midgut pH may be one factor contributing to the limitation of the host plant range of many species of lepidopteran herbivores.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020946203089
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  • 86
    Digitale Medien
    Digitale Medien
    Isolation, taxonomic and fermentation studies on a new strain of Streptomyces arenae var ukrainiana producing a tetraene antibiotic (1999)
    Springer
    World journal of microbiology and biotechnology 15 (1999), S. 545-552 
    Details
    ISSN: 1573-0972
    Schlagwort(e): Fermentation ; polyene antifungal antibiotic ; Streptomyces ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract A Streptomyces strain UK10 was isolated from Ukrainian soil and identified by taxonomical studies as Streptomyces arenae var ukrainiana. HA-2-91 was isolated from the biomass of S. arenae var ukrainiana and is supposedly a polyene macrolide antibiotic belonging to the tetraene group. HA-2-91 showed promising antifungal activity (in vitro) against yeasts and filamentous fungi, including plant pathogens and dermatophytes and was found to be less toxic in mice than nystatin and rimocidin.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008981528959
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  • 87
    Digitale Medien
    Digitale Medien
    Sex Pheromone Components of Casuarina Moth, Lymantria xylina (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 2535-2545 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Lepidoptera ; Lymantriidae ; Lymantria xylina ; Lymantria dispar ; Lymantria monacha ; Lymantria fumida ; sex pheromone ; reproductive isolation ; (7R,8S)-cis-7,8-epoxy-2-methyleicosane ; (7S,8R)-cis-7,8-epoxy-2-methyleicosane ; 2-methyl-Z7-eicosene ; (7R,8S)-cis-7,8-epoxy-2-methylnonadecane ; (7S,8R)-cis-7,8-epoxy-2-methylnonadecane ; (7R,8S)-cis-7,8-epoxy-3-methylnonadecane ; (7S,8R)-cis-7,8-epoxy-3-methylnonadecane ; disparlure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract cis-7,8-Epoxy-2-methyleicosane is a sex pheromone component of the Casuarina moth, Lymantria xylina Swinhoe. The compound was extracted from pheromone glands of female moths and was identified by coupled gas chromatographic–electroantennographic detection (GC-EAD) and GC–mass spectrometry. In field experiments in Taiwan, traps baited with either or both of (7R,8S)-cis-7,8-epoxy-2-methyleicosane (〉99% ee) [termed here (+)-xylinalure] and (7S,8R)-cis-7,8-epoxy-2-methyleicosane (〉99% ee) [termed here (−)-xylinalure] captured male L. xylina. Addition of further candidate pheromone components to xylinalure did not enhance its attractiveness. Demonstration of whether or not female L. xylina produce both optical isomers of xylinalure, and determination of the ratio, will require pheromone extract analyses on a chiral, enantiomer-separating column (as yet unavailable) or derivatization of epoxides in accumulated gland extracts. Attraction of male L. xylina to either enantiomer of xylinalure contrasts with enantiospecific production of, and/or response to, epoxy pheromones in congeners. With no other nocturnal lymantriid moth known in Taiwan to utilize xylinalure for pheromonal communication, enantiospecific “fine tuning” of xylinalure, or evolution of a more complex pheromone blend, may not have been necessary for L. xylina to maintain specificity of sexual communication. Racemic xylinalure will be appropriate for pheromone-based detection surveys of L. xylina in North America.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020830309624
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  • 88
    Digitale Medien
    Digitale Medien
    Identification and Field Evaluation of Components of Female Sex Pheromone of Millet Stem Borer, Coniesta ignefusalis (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 2643-2663 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Coniesta ignefusalis ; Acigona ignefusalis ; Lepidoptera ; Pyralidae ; sex pheromone ; (Z)-7-dodecen-1-ol ; (Z)-5-decen-1-ol ; (Z)-7-dodecenal ; (Z)-7-dodecenyl acetate ; (Z)-9-tetradecen-1-ol
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Five active compounds were detected during analyses of ovipositor washings and effluvia from virgin female Coniesta ignefusalis moths by gas chromatography (GC) linked to electroantennographic (EAG) recording from a male moth. These were identified as (Z)-7-dodecen-1-ol (Z7–12:OH), (Z)-5-decen-1-ol (Z5–10:OH), (Z)-7-dodecenal (Z7–12:Ald), (Z)-7-dodecenyl acetate (Z7–12:Ac), and (Z)-9-tetradecen-1-ol (Z9–14:OH) by comparison of their GC retention times, mass spectra, and EAG activities with those of synthetic standards. Laboratory tests of dispensers for these compounds showed that release rates from polyethylene vials increased to relatively uniform values after three to four days, but release from septa was very rapid and nonuniform and decreased to low levels after two to three days. Trapping tests in Niger showed that the major component, Z7–12:OH, and two of the minor components, Z5–10:OH and Z7–12:Ald, were essential for attraction of male C. ignefusalis moths. The most attractive blend contained these three components in a 100:5:3.3 ratio in a polyethylene vial, which emitted the components in similar proportions to those produced by the female C. ignefusalis moth. Water traps baited with this blend containing 1 mg of Z7–12:OH caught more male C. ignefusalis moths than traps baited with newly emerged female moths. Addition of up to 10% of the corresponding E isomers of the pheromone components had no effect on catches, but addition of the other two minor components detected, Z7–12:Ac and/or Z9–14:OH, to the attractive blend at naturally occurring levels caused significant reductions in trap catch.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020839221609
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  • 89
    Digitale Medien
    Digitale Medien
    Characterization of Pheromone Blend for Grapevine Moth, Lobesia botrana by Using Flight Track Recording (1999)
    Springer
    Journal of chemical ecology 25 (1999), S. 389-400 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Lepidoptera ; Tortricidae ; Lobesia botrana ; grapevine moth ; wind tunnel ; behavior ; flight track recording ; (E)-7,(Z)-9-dodecadienyl acetate ; (E)-7,(Z)-9-dodecadien-1-ol ; (Z)-9-dodecenyl acetate ; (E)-9-docecenyl acetate ; 11-dodecenyl acetate ; pheromone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The behavioral responses of Lobesia botrana males to calling females, pheromone gland extracts, and synthetic sex pheromones were recorded in a wind tunnel. Gland extracts and synthetic pheromones were released from a pheromone evaporator. The numbers of males reaching the source and their flight tracks in response to calling females and pheromone gland extracts were compared to those of synthetic blends. Upwind flights to natural sex pheromone were straighter and faster than to a three-component blend of (E)-7,(Z)-9-dodecadienyl acetate (E7,Z9–12:Ac), (E)-7,(Z)-9-dodecadien-1-ol (E7,Z9–12:OH), and (Z)-9-docecenyl acetate (Z9–12:Ac) (100:20:5). The optimum ratio of E7,Z9–12:OH and Z9–12:Ac to E7,Z9–12:Ac was found to be 5% and 1%, respectively. An additional seven compounds identified in the sex pheromone gland were investigated for their biological activity. Two unsaturated acetates, i.e., (E)-9-dodecenyl acetate (E9–12:Ac) and Δ11-dodecenyl acetate (Δ11–12:Ac), increased the number of males reaching the source as well as straightness, linear velocity, and decreased the track angle of upwind flight. Optimum response was obtained by releasing 10 pg/min E7,Z9–12:Ac in a mixture with 0.5 pg/min E7,Z9–12:OH, 0.1 pg/min Z9–12:Ac, 0.1 pg/min E9– 12:Ac and 1 pg/min Δ11-12–Ac. The saturated acetates previously identified in the female glands were biologically inactive.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1020811200054
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  • 90
    Digitale Medien
    Digitale Medien
    A review of the genus Cobitis in Turkey (Pisces: Ostariophysi: Cobitidae) (1999)
    Springer
    Hydrobiologia 403 (1999), S. 13-26 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Cobitidae ; Cobitis ; taxonomy ; new subgenus ; Turkey
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract In the rivers and lakes of Turkey, ten species of loaches of the genus Cobitis occur, viz. C. fahireae, C. varderensis, C. splendens, C. kellei, C. puncticulata, C. strumicae, C. levantina, C. turcica, C. simplicispina and C. bilseli. Cobitis bilseli is separated into a new subgenus, Beyshehiria.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003794726444
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  • 91
    Digitale Medien
    Digitale Medien
    Redescription of Macrothrix laticornis (Jurine, 1820), and description of two new species of the M. laticornis-group (1999)
    Springer
    Hydrobiologia 403 (1999), S. 39-61 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Macrothrix laticornis-complex ; morphology ; taxonomy ; distribution ; males
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Macrothix laticornis is redescribed and compared with populations from central North America (Mexico), and from south-east Asia (Vietnam). All three are closely related, but with sufficient morphological differences to establish a laticornis species-group. Two species new for science are described, viz. M. sierrafriatensis (Mexico) and M. vietnamensis (Vietnam).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003776325401
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  • 92
    Digitale Medien
    Digitale Medien
    Redescription of Macrothrix tripectinata Weisig, 1934 (Anomopoda, Branchiopoda), with a discussion of some features rarely used in the systematics of the genus (1999)
    Springer
    Hydrobiologia 403 (1999), S. 63-80 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Branchiopoda ; ‘Cladocera’ ; Anomopoda ; Macrothrix tripectinata ; morphology ; redescription ; taxonomy ; key ; Eurasia ; distribution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The rare Macrothrix tripectinata Weisig, 1934 is redescribed on material from the East Pamirs (Tajikistan) and Tuva (Russia). Adult and juvenile parthenogenetic females and adult males were studied using optical microscopy and SEM. The thoracic appendages and the molar surface of mandibles were investigated in detail. Selected ‘conventional’ diagnostic features are critically reviewed. The importance of characters, rarely used in the systematics of Macrothrix, such as: type of valve reticulation, similarity or dissimilarity in size of the terminal esthetascs of the antennules of females and males, presence of an abdominal projection and reticulation on the postabdomen, presence, length and armature of a male seta on the antennule, are discussed. A key for the Eurasian species of Macrothrix is proposed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003714909471
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  • 93
    Digitale Medien
    Digitale Medien
    The genus Thermocyclops Kiefer, 1927 (Copepoda: Cyclopidae) in China (1999)
    Springer
    Hydrobiologia 403 (1999), S. 87-95 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Thermocyclops ; China ; taxonomy ; distribution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Based on the result of investigations and former records, there are five freshwater species of the genus Thermocyclops in China, namely T. taihokuensis Harada, 1931, T. crassus (Fischer, 1853), T. vermifer Lindberg, 1935, T. dybowskii (Lande, 1890), and T. kawamurai Kikuchi, 1940. Two previously recorded species, T. brevifurcatus Harada, 1931 and T. hyalinus (Rehberg, 1880) are recognized as synonyms of Thermocyclops crassus. Another species, Thermocyclops mongolicus Kiefer, 1937, described from China by Tai & Chen, is a synonym of T. taihokuensis based on this study. Thermocyclops orientalis Dussart & Fernando, 1985 was compared with Thermocyclops kawamurai Kikuchi, 1940. It shows conspicuous differences and it seems unlikely that it is a synonym of T. kawamurai. The paper presents diagnostic characteristics of each species and a key to five Chinese species of Thermocyclops.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003761106940
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  • 94
    Digitale Medien
    Digitale Medien
    Studies on the aquatic oligochaete fauna in Lake Biwa, central Japan. II. Records and taxonomic remarks of nine species (1999)
    Springer
    Hydrobiologia 406 (1999), S. 33-47 
    Details
    ISSN: 1573-5117
    Schlagwort(e): aquatic Oligochaeta ; Lake Biwa ; Japan ; taxonomy ; zoogeography
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract At least 41 taxa of aquatic oligochaetes including five new records have been recorded from the ancient Lake Biwa in Japan. The lake is characterized by eurybathyal occurrence of Branchiura sowerbyi. The posterior gill filaments of B. sowerbyi develop normally in lagoons adjacent to the lake, while in the lake they weakly develop or often disappear at littoral and sublittoral depths shallower than 30 m, and they almost completely disappear in the profundal zone. The profundal population of B. sowerbyi also differs from other populations in eastern Asia in having fewer and shorter hairs, and simple-pointed crotchets, or bifid crotchets with parallel teeth, in dorsal bundles of chaetae. This suggests that an intralacustrine speciation is progressing in the profundal population. An aberrant modification is found in the pectination of dorsal crotchets in Tubifex tubifex occurring at deep profundal depths of the lake. The ventral chaetae in segment II of Teneridrilus mastix are rarely modified in Lake Biwa. This requires cancellation of the modification of chaetae in II as a diagnostic characteristic of the genus Teneridrilus. Limnodrilus amblysetus, previously known only from China, is recorded from Lake Biwa. Descriptions and taxonomic remarks are provided for Haemonais waldvogeli (new to Japan), Pristina longiseta, Stephensoniana trivandrana and Ripistes parasita (new to Lake Biwa), and Ophidonais serpentina, based on Lake Biwa material.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003795311154
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  • 95
    Digitale Medien
    Digitale Medien
    Marine benthic algae of North East Herald Cay, Coral Sea, South Pacific (1999)
    Springer
    Hydrobiologia 398-399 (1999), S. 65-74 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Australia ; Coral Sea ; marine algae ; taxonomy ; biogeography
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The marine benthic algae from North East Herald Cay, Coral Sea, South Pacific, are listed with taxonomic, bibliographic and biogeographic details. The checklist includes 66 species of which 23 are green, 2 are brown, and 41 are red algal species. The almost complete absence of brown algae from what is seemingly a typical tropical reef environment on which a true coral cay has developed is noteworthy. All samples were from the lagoon, which forms the concave side of a crescent-shaped reef and which ranges in depth from 0–30 m. The endemic Caribbean green alga Chamaedoris peniculum is recorded for the Pacific for the first time, and a possibly undescribed species of the genus Rhipiliopsis was also discovered. Although only preliminary, the survey shows that the marine flora is seemingly typical of coral cays for the general region of the Great Barrier Reef.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1017017906282
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  • 96
    Digitale Medien
    Digitale Medien
    Retrospect and Prospect: reflections on forty years of study of aquatic oligochaetes (1999)
    Springer
    Hydrobiologia 406 (1999), S. 9-19 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Annelida ; Clitellata ; history ; taxonomy ; ecology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Fourteen aquatic oligochaetes were described between 1773 and 1828. Dramatic increases in descriptions occurred in the decades beginning 1900, 1930 and 1960. These can be associated with specific authors, such as W. Michaelsen and S. Hrabě. In the period 1970–1990, some 250 marine species (excluding Enchytraeidae) were described, largely by C. Erséus. Some of the major scholars, such as W. Michaelsen and F. Vejdovský, I. I. Malevič and P. G. Svetlov, founded centers of oligochaete study that survive in Europe today. Others, such as those in the English speaking world, have had to develop in isolation. While numerical and phenetic methods had little influence on microdrile systematics, phylogenetic (parsimony) methods have, since the first publication by B. G. M. Jamieson. Most literature prior to 1970 was taxonomic. Other earlier work documented community structure in relation to pollution. The study of Rybinsk Reservoir (Russia) stimulated a large body of ecological and biological work by T. L. Poddubnaya. The St. Lawrence Great Lakes was also a focus for worm studies until recently. Early physiological work focused on respiration, with studies dating from the 1920s. This has been continued in relation to pollution ecology and energy flow. Physiological work was notably absent from our first proceedings volume and only poorly represented since then. Future prospects are difficult to identify. Developments in ultrastructure (including sperm and muscle cells), molecular biology and parsimony or cladistic phylogenetic methods will move from rather simple initial work that shows the possibilities, to a revisionary phase where the complexities begin to be revealed before it is possible to assess their value. This author has too superficial a level of understanding to predict the outcome, but suspects that agreement among the results of several methods is needed for them to be persuasive. I would hope that multivariate methods of data analysis in pollution studies would prove superior to the development of indices and over-reliance on toxicology. Toxicity studies are of use in comparing risks among products but not in predicting field effects. Benthic biology needs a method for identifying factors that are directly related to worm biology, such as food, rather than physical and chemical factors related to the water column. Surveys, relating communities to chemical and physiographic factors will remain unpredictive. It is easier to forsee some changes in taxonomy that are almost overdue. The haplotaxids should be broken up into several small families, Haplotaxis s.s. will be one of them, with a number of highly adapted and very similar species, many currently regarded as synonymous, redefined by careful anatomical study. The lumbriculids and branchiobdellidans may well be combined into a single taxon defined by their unique semi-prosopore male ducts, with lumbriculids defined by their unique muscle structure and the branchiobdellids by many apomorphic characters related to ectocommensal life. The position of Hirudinea remains unresolved, but relationship to this taxon is not excluded. Detailed study of penes in lumbriculids is required. The naidids and tubificids seem to be a monophyly. Existing genera may be hard to analyze phylogenetically because definitions are based on atrial form, which is hard to express as characters. Chaetotaxy in Naididae will prove insufficient and many synonyms will be declared. Capilloventridae and Randiellidae require description of male ducts and gonads. They may provide evidence counter to the octogonadal theory of oligochaete descent, or of polyphyly in the group. Knowledge of phreodrilid diversity will increase. Work will increase in Asia and South America, but sub-Saharan Africa remains under explored. Fish diseases will create more interest in North American worms. New methods, including molecular studies, and renewed interest in ontogeny and detailed anatomical studies, may improve our ability to resolve clusters of taxa with few, if any, apomorphic character states that remain at the base of cladograms. An ability to include sound evidence from vestigial organs and logical arguments on a 'weight of evidence' basis is needed as an adjunct. While molecular studies seem to hold much promise, early studies can prove over simplistic and can provide conflicting hypotheses. We need to complete the review of taxonomy according to parsimony before major terminology changes, such as abandonment of the term Oligochaeta, can gain acceptance.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003788219293
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  • 97
    Digitale Medien
    Digitale Medien
    Taxonomic and systematic assessment of planktonic copepods using mitochondrial COI sequence variation and competitive, species-specific PCR (1999)
    Springer
    Hydrobiologia 401 (1999), S. 239-254 
    Details
    ISSN: 1573-5117
    Schlagwort(e): mitochondrial DNA ; cytochrome oxidase I ; competitive PCR ; copepoda ; taxonomy ; marine zooplankton
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Accurate taxonomic identification of species at all life stages is critical to understand and predict the processes that together determine marine community dynamics. However, zooplankton assemblages may include numerous sibling and congeneric species distinguished by subtle morphological characteristics. Molecular systematic databases, including DNA sequences of homologous gene regions for selected taxonomic groups, allow the design of rapid protocols to determine species' diversity and identify individuals. In this study, the DNA sequence of a 300 base-pair region of the mitochondrial cytochrome oxidase I (COI) gene was determined for eight species of three genera of calanoid copepods: Calanus finmarchicus, C. glacialis and C. helgolandicus; Neocalanus cristatus, N. flemingeri and N. plumchrus; and Pseudocalanus moultoni and P. newmani. The DNA sequences differed between congeneric species by 13 – 22% of the nucleotides; the protein sequences differed by zero to five amino acid substitutions. Both the DNA and amino acid sequences resolved the evolutionary relationships among congeneric species; relationships among the genera were not well-resolved by this region of mtCOI. Using the same conserved primers, the only amplification product for C. finmarchicus was an aberrant sequence (and putative pseudogene) which differed from the C. finmarchicus COI sequence by 36% of the nucleotides and 32 amino acid substitutions. Species-specific oligonucleotide primers were designed for Calanus spp. (which cannot be distinguished at larval stages) and Pseudocalanus spp. (which are difficult to distinguish even as adults). Individual copepods were identified using competitive, multiplexed species-specific polymerase chain reactions (PCR) in two studies of co-occurring sibling species. The first study confirmed the presence of three Calanus spp. in Oslofjord, Norway and found a predominance of C. helgolandicus. The second study determined patterns of distribution and abundance of Pseudocalanus spp. on Georges Bank in the NW Atlantic and showed that P. moultoni predominated in shallow and coastal waters, while P. newmani was more abundant in offshore regions flanking the Bank. Competitive, species-specific PCR is a useful tool for biological oceanographers. This simple, rapid, and inexpensive assay may be used to identify morphologically-similar individuals of any size and life stage, and to determine a species' presence or absence in pooled samples.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003790411424
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  • 98
    Digitale Medien
    Digitale Medien
    Fish species – how and why (1999)
    Springer
    Reviews in fish biology and fisheries 9 (1999), S. 325-352 
    Details
    ISSN: 1573-5184
    Schlagwort(e): evolution ; nomenclature ; phylogeny ; species ; systematics ; taxonomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract It is argued, with selected examples from freshwaterfish systematics, that species should be viewed as anexpression of self-perpetuated clustered variation innature, conforming to the phylogenetic speciesconcept. The importance of species lies in thefunctional and structural significance of theirdiagnostic characters. Species can be nested by theircharacters into a tree diagram (phylogeny) orhierarchical alignment structure (classification) ofcharacter distribution, which may be taken to reflectevolution, the unifying theory of organismaldiversification. The phylogenetic species concept,which emphasizes recognition of a pattern ofvariation, describes better than any other proposedconcept the units called species by systematists.Other concepts are based on processes and normally donot permit recognition of particular taxa. Specieshave unique histories, and speciation may proceed bydifferent mechanisms. Whereas it may be postulatedthat speciation entails an irreversible change in thegenetic structure of taxa, recognized by phenotypicexpression and apparently also maintained to a largeextent by selection for a particular phenotype,species recognition must remain independent ofassumptions about species history and spatialdistribution. Species are monophyletic taxa and thespecies category does not differ significantly inphylogenetic regard from other systematic categories.Species as such are not necessarily evolutionaryunits. It is recommended to apply species names withreference to the diagnostic characters of the speciesand to abandon the type specimen described by theInternational Code of Zoological Nomenclature as anomenclatural reference unit.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008959313491
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  • 99
    Digitale Medien
    Digitale Medien
    Electrophysiological and ultrastructural correlates of cryoinjury in sciatic nerve of the freeze-tolerant wood frog, Rana sylvatica (1999)
    Springer
    Journal of comparative physiology 169 (1999), S. 351-359 
    Details
    ISSN: 1432-136X
    Schlagwort(e): Key words Freeze tolerance ; Sciatic nerve ; Cryoinjury ; Dehydration ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract We investigated function and ultrastructure of sciatic nerves isolated from wood frogs (Rana sylvatica) endemic to the Northwest Territories, Canada, following freezing at −2.5 °C, −5.0 °C, or −7.5 °C. All frogs frozen at −2.5 °C, and most frogs (71%) frozen at −5.0 °C, recovered within 14 h after thawing began; however, frogs did not survive exposure to −7.5 °C. Sciatic nerves isolated from frogs frozen at −7.5 °C were refractory to electrical stimulation, whereas those obtained from frogs surviving exposure to −2.5 °C or −5.0 °C generally exhibited normal characteristics of compound action potentials. Frogs responded to freezing by mobilizing hepatic glycogen reserves to synthesize the cryoprotectant glucose, which increased 20-fold in the liver and 40-fold in the blood. Ultrastructural analyses of nerves harvested from frogs in each treatment group revealed that freezing at −2.5 °C or −5.0 °C had little or no effect on tissue and cellular organization, but that (lethal) exposure to −7.5 °C resulted in marked shrinkage of the axon, degeneration of mitochondria within the axoplasm, and extensive delamination of myelin sheaths of the surrounding Schwann cells.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s003600050231
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  • 100
    Digitale Medien
    Digitale Medien
    Echinococcus granulosus: praziquantel treatment against the metacestode stage (1999)
    Springer
    Parasitology research 85 (1999), S. 999-1006 
    Details
    ISSN: 1432-1955
    Schlagwort(e): Key wordsEchinococcus granulosus ; Praziquantel ; Metacestode ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract The efficacy of praziquantel against the metacestode of Echinococcus granulosus was studied by means of in vitro incubations or in vivo experiments. The results of in vitro incubations indicated that the effectiveness of praziquantel was higher when the parasite material comprised cysts from cyst masses than in the case of intact cysts that retained their adventitial layer. Ultrastructural alterations in the germinal layer of collapsed cysts incubated in vitro were detected. The results obtained in mice after 4 months of treatment demonstrated no significant difference between the control and treated groups with regard to the number and wet weight of developed cysts. However, ultrastructural alterations were detected in the cyst tissue that were similar to those described in the in vitro experiment. In contrast, the effect of chemoprophylaxis on the number and the wet weight of developed cysts was extremely significant as compared with the control value, the efficacy being 99.41% and 98.32%, respectively. Moreover, ultrastructural observations of the cyst tissue revealed loss of its integrity, and no intact cyton was observed in the germinal layer of the developed cyst.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004360050672
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