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  • Hymenoptera  (282)
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  • Turbulence
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  • 101
    Electronic Resource
    Electronic Resource
    Springer
    Pure and applied geophysics 120 (1982), S. 758-771 
    ISSN: 1420-9136
    Keywords: Diffusion ; Turbulence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Dye plumes were generated at three depths in the seasonal thermocline between 7 and 11 m, 22 km south of Key West on 21 August 1980 and photographed at about 10 second intervals with an underwater camera system. Eleven pairs of consecutive pictures are analyzed to determine the mean current vertical shear and the width of the plumes by positioning reference points relative to the rod attached to the camera system. The relative distances of reference points are calibrated with the stereophotogrammetric method for one pair. The eddy diffusivity is calculated by use of a model of turbulent diffusion developed byTaylor (1921). Its values range from 5 to 25 cm2s−1 for the plume widths ranging from 33 to 132 cm. The Richardson number is calculated for each pair of pictures with the vertical density gradient estimated from temperature profiles. Its values are higher than the critical value of 0.25 except for one case. The diffusivity was higher by orders of magnitude than the molecular one and indicates the presence of turbulence together with billow like features of the plumes in spite of high Richardson numbers. This suggests that the billow turbulence might be caused by effects of surface gravity waves and not by the Kelvin-Helmholtz instability.
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  • 102
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    Pure and applied geophysics 132 (1990), S. 457-479 
    ISSN: 1420-9136
    Keywords: Turbulence ; mesures aéroportées ; fluctuation de pression ; presso-corrélations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Résumé Nous avons décrit dansBardeau et al. (1987), la réalisation, le fonctionnement et les tests d'un microdébitmètre basé sur l'anémométrie à fil chaud. Il a été particulièrement montré que cet appareil était bien adapté aux mesures de pression et pression différentielle avec une grande sensibilité et une très faible constante de temps. Nous présentons ici les applications qui ont été faites de ce capteur aux mesures à haute résolution à bord d'avions instrumentés pour la recherche atmosphérique. L'avion utilisé était spécialement équipé pour les mesures de turbulence et permettait donc l'acquisition d'un grand nombre de paramètres indispensables à l'analyse des données de ce capteur. Dans les applications aéronautiques qui ont été faites, le capteur a surtout été utilisé en tant que variomètre. Les comparaisons avec les mesures standards d'altitude par pression et couplages pression-données inertielles montrent que cet instrument pourrait apporter une contribution intéressante dans le domaine de la mesure à haute fréquence des fluctuations de pression.
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  • 103
    ISSN: 1420-9098
    Keywords: Hymenoptera ; social wasps ; sociotomy ; behaviour ; Ropalidia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Females of an Australian polistine wasp,Ropalidia plebeiana, often use their mandibles to cut their nest-comb in spring, dividing it into two or more completely independent nests. Prior to the division, each of the major egg layers, often with some subordinates, tended to occupy a different part of a single comb. These females gnawed cells in the intermediate zone between such “territories”, and ultimately divided the comb. Many other females also built new nests near the nest aggregations, but addition of new nests by comb cutting represented 34.8 % of the increase in nest number. This method of colony fission is so far unknown in any eusocial Hymenoptera.
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  • 104
    ISSN: 1420-9098
    Keywords: Hymenoptera ; social wasps ; Polybia ; prey capture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Polybia sericea (Hymenoptera: Vespidae) prey foraging was studied by following individual foragers as they hunted in the field, by observing how wasps handled prey once they had captured it, and by observing wasps as they returned to the nest with prey. Wasps were most likely to forage for prey between 0700 and 1300 hours and between 1600 and 1700 hours. The prey foraging sequence consisted of the behaviours high flight, search, touch, land, groom, walk, bite and malaxate. Captured small prey were malaxated and carried to the nest. Wasps removed the gut from large prey and dragged the meat up a twig or grass stem. A load of the meat was then bitten off and malaxated; the remainder was cached while the wasp made an orientation flight and returned to the nest. The forager returned within minutes for the remainder of the prey. Experiments demonstrated that caching the prey remains above the ground rather than close to the ground, where the prey are generally captured, reduces the chance that the prey will be found and expropriated by ants.
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  • 105
    ISSN: 1420-9098
    Keywords: Hymenoptera ; ants ; Messor ; pleometrosis ; queens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Starting colonies of the desert seed-harvester antMessor pergandei are clumped in the field and face severe intraspecific competition through brood raiding. Single foundress laboratory colonies ofM. pergandei are more likely to succeed at brood raiding with conspecific colonies if they are given additional workers and mature pupae several days prior to brood raiding. Per foundress fecundity remains constant across laboratory starting colonies established with 1, 3 and 5 foundresses. These results suggest that the selective advantage of cooperative colony foundation (pleometrosis) in this and similar species may derive directly from the ability of multiple foundresses to produce a larger brood raiding force.
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  • 106
    ISSN: 1420-9098
    Keywords: Kin recognition ; social wasp ; Ropalidia marginata ; evolution of sociality ; Hymenoptera ; Vespidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Female wasps of the tropical primitively eusocial speciesRopalidia marginata are known to discriminate unfamiliar nestmates from unfamiliar non-nestmates outside the context of their nests. Here, we show that when foreign conspecifics are introduced in the context of a nest in laboratory cages, genetic relatives among them are treated by nest inhabitants more tolerantly than non-relatives, but that no foreign conspecifics are accepted into the nests. However, some wasps may leave their nest and join the foreign relatives and non-relatives to found new colonies cooperatively. Very few of the introduced animals are severely attacked or killed; most are allowed to remain in parts of the cage away from the nest. These results suggest that factors other than genetic relatedness may be involved in regulating tolerance and acceptance of foreign conspecifics on a nest and its vicinity. Our results are different from those of similar experiments with ants, which have demonstrated that former nestmates that are removed as pupae and later introduced as adults are either accepted into the nest or attacked and killed. We attribute this difference to the fact that in a primitively eusocial species such asR. marginata, the rules governing tolerance and acceptance of foreign conspecifics must be quite different from those in highly eusocial species. We also attempt to test some predictions of the conspecific acceptance threshold models of Reeve (Am. Nat. 133:407–435, 1989). Our results uphold the predictions of his “fitness consequence submodel” but do not support those of his “interaction frequency sub-model”.
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  • 107
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    Aquatic sciences 54 (1992), S. 58-76 
    ISSN: 1420-9055
    Keywords: Eutrophication ; lake management ; phosphorus ; nitrogen ; chlorophyll-a ; slope estimator
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We estimate the response of chl-a (mg · m−3) to changes in concentrations of total phosphorus (TP) by calculating the slopeS = Δchl-a/ΔTP in chl-a =f(TP) graphs. Results show that in years where algae are P-limited oligotrophic lakes respond less (median slope 0.21) to changes in nutrient concentrations than eutrophic lakes, (median slope 0.31) and these again less than hypereutrophic lakes, (median slope 1.02). We find no saturation value for the slope within the TP range considered (6–480 mg · m−3). Chl-a in eutrophic lakes responds more frequently to non-nutrient factors than oligotrophic and hypereutrophic lakes. Results obtained by replacing TP with a new nutrient parameter, TP′ = 0.056 · TP · IN0.226, in which inorganic nitrogen, IN, is factored in, suggest that nitrogen has an influence on chl-a in oligotrophic lakes. Blue-green algae respond less to changes in TP than other algal species, e.g., diatoms.
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  • 108
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    Aquatic sciences 54 (1992), S. 381-390 
    ISSN: 1420-9055
    Keywords: Eutrophication ; phosphorus ; lake restoration ; internal restoration measures for lakes ; Swiss lakes ; Lake Lugano (Lago di Lugano)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In most lakes eutrophication is linked to an excessive input of phosphorus. Lake restoration by reduction of P-input (external measure) has led to a considerable drop of the P-concentration in all major Swiss lakes as well as in many other lakes. Internal restoration measures such as artificial mixing, drainage of hypolimnetic water, flushing, aeration, biomanipulation and others serve to improve and accelerate the response of a lake to external measures. For the case of Lago di Lugano, a simple two-box model is employed to demonstrate that a reduction of the P-input to about 25% of the present values is necessary to reach the “P-criterion” (P-concentration below 30 µg/l). Internal measures could possibly accelerate the extremely slow response of the northern basin.
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  • 109
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    Aquatic sciences 55 (1993), S. 132-142 
    ISSN: 1420-9055
    Keywords: nitrogen ; phosphorus ; uptake ; regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Dissolved inorganic nutrient pools are small relative to particulate pools, and dissolved pools turnover rapidly. It has been observed that pools change little from day to day on the sampling scales usually employed. A simple model is presented where uptake and regeneration rates balance to cause a local steady state concentration for dissolved inorganic nutrients. Enrichment and dilution perturbation experiments with lake water support the idea of steady state nutrient concentrations. Although inorganic nutrient concentrations are often controlled by biota, the absolute concentrations present tell little about the activity of that biota.
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  • 110
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    Aquatic sciences 56 (1994), S. 16-28 
    ISSN: 1420-9055
    Keywords: Chlorophyll-a ; phosphorus ; nitrogen ; lake ecosystem ; nutrient limitation ; regression analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Regression results based on data from 46 northern temperate lakes show that total phosphorus (TP) is the best predictor for phytoplankton (as chl-a) at lower trophic levels, TP 〈 200 mg · m−3. A regression including both TP and TN as regressors is the best predictor for lakes with TP 〉 200 mg · m−3. However, the good correlation is probably due to a high correlation between lake average chl-a (all years observed) and lake average TP and TN. Within single hypereutrophic lakes, TN alone is the best predictor. It was not possible to identify a medium trophic domain where TN and TP in combination was the best predictor for chl-a. The ratio TN:TP in the water decreases from about 40 to about 5 with increasing trophic level. Optimum TN:TP ratio for algal species with high abundance during late summer and autumn reflects this decreasing ratio, but within a lesser range, i.e., 20 to 5. In contrast, TN:TP ratios for species abundant during the early vernal period showed no, or an inverse, relation to the TN:TP ratio of the water.
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  • 111
    ISSN: 1432-0495
    Keywords: Nitrogen ; phosphorus ; Precipitation collector ; Nutrients rates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The contribution of nitrogen and phosphorus due to precipitation constitutes the second most important route after superficial runoff. The sampling carried out during a two-year period by means of a precipitation collector allows us to determine the contribution of this route both qualitatively and quantitatively. Nitrogen is mainly supplied in an inorganic form, while phosphorus is principally supplied as orthophosphate. During the period of this study (March 1986–February 1988) it was found that in the Santillana Reservoir Watershed the level of nitrogen supplied by precipitation constitutes an average of 4.87% and the level of phosphorus constitutes 8.01%. The contribution of nitrogen varies in inverse ratio to precipitation and the contribution of phosphorus varies in direct ratio.
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  • 112
    ISSN: 1423-0445
    Keywords: euglossine flowers ; perfume collection ; euglossophily ; floral fragrant exudates ; nesting behaviour ; mating behaviour ; bee pheromones ; nest mimicry ; signal evolution ; Hymenoptera ; Apidae ; Euglossinae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A fascinating pollination system has been evolved between perfume producing flowers and perfume collecting male euglossine bees in the neotropics. Detailed investigations have contributed to an understanding of the interactions between euglossine males and flowers as a pollination system. The role which the collected perfume plays in the reproductive behaviour of euglossine bees is not fully understood. A favoured hypothesis suggests that the collected fragrances are used as precursors for male sex pheromones and thus serve to attract conspecific males or females. It is not known how perfume collection behaviour evolved. Here, an evolutionary approach presents a new hypothesis which suggests that the evolution of perfume collection in euglossine males is based upon pre-existing signals which were attractive to females and males. It is further suggested that, at the evolutionary outset, flowers mimicked nest sites to deceive nest-seeking euglossine bees. In addition, a comparative study was undertaken on the phenomena of nest-mimicking flowers in related bee families.
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  • 113
    ISSN: 1432-041X
    Keywords: Athalia rosae ; Hymenoptera ; Thelytoky ; Automixis ; Gynandromorph
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Mature eggs dissected from ovaries of unmated females of Athalia rosae (Hymenoptera: Tenthredinidae), if placed on a filter-paper soaked with distilled water, are activated and develop to haploid males. Occasionally, however, diploid females develop from these artificially activated eggs. Treatment of mature unfertilized eggs dissected from diploid females with ice-cold temperatures immediately before activation and with a high temperature (36° C) upon and immediately after activation resulted in the production of diploid males, diploid females, triploid females and gynandromorphs at high frequency. The same treatment of mature unfertilized eggs dissected from triploid females resulted in the production of only triploid survivors. These results, together with the results on the segregation of a marker mutation, yellow fatbody (yfb), appear to indicate that meiotic divisions were complete in the treated eggs, and that all four nuclei became potentially capable of participating in development with or without automictic fusion.
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  • 114
    ISSN: 1423-0445
    Keywords: chemical communication ; queen cells ; brood pheromone ; brood recognition ; fatty acid esters ; Hymenoptera ; Apidae ; Apis mellifera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Honey bee workers are able to nurse or to destroy and thus to recognize the capped queen cells containing a pupa. Fatty acid esters, especially methyl oleate, methyl palmitate and ethyl oleate were found in significant amounts on the queen pupal cuticle. Methyl oleate, the major component, along with smaller amounts of methyl linoleate and methyl linolenate, were involved in the recognition of queen cells by workers. In natural conditions of the colony, queen cells containing a paraffin pupal lure with methyl oleate were accepted 5.9 days by workers, releasing about 1.8 queen pupa equivalents during that period, when control cells (without ester) were kept only 2.1 days. Although these esters are non specific to honey bees, they are of great importance in social regulation of the honey bee colony.
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  • 115
    ISSN: 1423-0445
    Keywords: predation ; plant-insect interactions ; tritrophic level interactions ; iridoid glycosides ; catalpol ; Lepidoptera ; Nymphalidae ; Junonia coenia ; Hymenoptera ; Formicidae ; Camponotus floridanus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We investigated the role of the iridoid glycoside, catalpol, as a deterrent to the predator,Camponotus floridanus. Four laboratory colonies of this ant were offered buckeye caterpillars (Junonia coenia: Nymphalidae) raised on diets with and without catalpol. The same colonies were offered sugar-water solutions containing varying concentrations of catalpol, in both no-choice and choice tests. Regardless of diet, buckeye caterpillars appeared to be morphologically protected from predation by the ants, possibly because of their large spines or tough cuticle. However, buckeyes raised on diets with catalpol had high concentrations of catalpol in their hemolymph; extracts of this high-catalpol hemolymph proved to be an effective deterrent to the ants. When starved ants were not given the choice of food items, they were more likely to consume sucrose solutions that contained 5 mg catalpol/ml or 10 mg catalpol/ml than they were to consume solutions with 20 mg catalpol/ml. When they were given a choice of sugar solution or a sugar solution containing catalpol, the ants avoided solutions with catalpol at any of these concentrations. Ant colony responses to catalpol in sucrose solutions varied considerably over time and among colonies.
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  • 116
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    Development genes and evolution 203 (1994), S. 450-453 
    ISSN: 1432-041X
    Keywords: Athalia rosae ; Hymenoptera ; Sperm injection ; Parthenogenesis ; Chimera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Mature unfertilized eggs (oocytes) dissected from the ovary of the sawfly Athalia rosae (Hymenoptera) begin parthenogenetic development if exposed to distilled water and produce haploid males. Injection of sperm into mature oocytes through the anterior pole resulted in karyogamy in a fraction of cases which developed as diploid females. No haploid-haploid chimeras due to independent participation of the injected sperm in development were produced. When sperm were injected through the posterior pole, however, fertilization never occurred but haploid-haploid chimeras were produced in a smaller fraction of cases. Both egg nucleus-derived and injected sperm-derived nuclei contributed in forming the germ cells of the chimeric males.
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  • 117
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    Chemoecology 4 (1993), S. 8-18 
    ISSN: 1423-0445
    Keywords: alkaloids ; feeding deterrence ; toxicity ; nectar ; pollen ; allelochemicals ; chemical defence ; Hymenoptera ; honeybee ; Apis mellifera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The influence of 63 dietary allelochemicals (alkaloids, terpenes, glycosides,etc.) on the feeding behaviour of bees (Apis mellifera) was tested in terms of deterrency and attraction. For 39 compounds a deterrent (mostly alkaloids, coumarins and saponins) and for 3 compounds an attractive response (mostly terpenes) was obtained in choice tests, which allowed the calculation of respective ED50-values. Under no-choice conditions, 17 out of 29 allelochemicals caused mortality at concentrations between 0.003 and 0.6%. Especially toxic were alkaloids, saponins, cardiac glycosides and cyanogenic glycosides. These data show that bees which are confronted with plant allelochemicals in nectar and pollen, are not especially adapted (i.e. insensitive) to the plants' defence chemistry. GLC and GLS-MS data are given on the alkaloid composition of nectar and pollen ofBrugmansia aurea, Atropa belladonna andLupinus polyphyllus.
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  • 118
    ISSN: 1432-041X
    Keywords: Oogenesis ; Oocyte polarity ; Accessory nuclei ; Hymenoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The progressive establishment of anteroposterior and dorsoventral polarity in developing oocytes ofCosmoconus meridionator is described. In fully grown oocytes, the asymmetrical (polar) organization is apparent in the localization of the oocyte nucleus (germinal vesicle) and oosome, and in the uneven (graded) distribution of lipid droplets, yolk spheres and specific organelles termed accessory nuclei (AN). The latter structures occur preferentially within the anteroventral periplasm. The developmental significance of AN is discussed.
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  • 119
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    Cellular and molecular life sciences 48 (1992), S. 902-904 
    ISSN: 1420-9071
    Keywords: Leptopilina boulardi ; Hymenoptera ; Eucoilidae ; parasitoid ; olfaction ; learning ; memory ; olfactometer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract FemaleLeptopilina boulardi wasps, larval parasites ofDrosophila melanogaster, can learn to respond to more than one odour by associating these odours with oviposition experience. These wasps can memorise and respond to at least two different odours, and prefer the last one learnt.
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  • 120
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    Oecologia 89 (1992), S. 147-149 
    ISSN: 1432-1939
    Keywords: Sex ratio ; Polyembryony ; Hymenoptera ; Parasitoid ; Copidosoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We examined brood sex ratios of an undetermined species of Copidosoma. Most broods (65%) were unisexual, with a greater proportion of female broods. Some mixed broods contained extremely small proportions of wasps of the opposite sex. Our results imply that the female-biased sex rations in this species cannot be explained by local mate competition theory.
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  • 121
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    Oecologia 95 (1993), S. 410-415 
    ISSN: 1432-1939
    Keywords: Clutch size ; Parasitoid ; Aphaereta minuta ; Hymenoptera ; Braconidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Clutch size decisions by Aphaereta minuta (Nees) (Hymenoptera: Braconidae), a polyphagous, gregarious, larval-pupal endoparasitoid, were studied under laboratory conditions. This parasitoid attacks larvae of Diptera inhabiting ephemeral microhabitats such as decaying plant and animal material. Females oviposit in young larval stages, but the eventual size of the host pupa determines host food availability for competing offspring. The size of the pupa can differ greatly between host species. We questioned how A. minuta females deal with this delay between the moment of oviposition and eventual host food availability, and whether they make clutch size decisions that benefit their fitness. It was shown that females indeed vary their clutch size considerably and in an adaptive way: (1) females lay larger clutches in larvae of host species that produce larger pupae, even when the larvae are the same size at the moment of oviposition, and (2) females lay larger clutches in larger larvae than in smaller larvae of the same host species. The latter seems functional as larvae parasitized at an older stage indeed developed into larger pupae compared to larvae parasitized at a younger stage. Furthermore, mortality of parasitized young host larvae was greater than that of both unparasitized larvae and parasitized older larvae. Under field conditions the risk of mortality of young host larvae is expected to be even higher due to the limited period of microhabitat (host food) availability, strong scramble type competition between the host larvae, and the longer period of being exposed to predation.
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  • 122
    ISSN: 1432-1939
    Keywords: Hymenoptera ; Eucoilidae ; Leptopilina heterotoma ; Infochemicals ; Kairomone ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Parasitoids that forage for herbivorous hosts by using infochemicals may have a problem concerning the reliability and detectability of these stimuli: host stimuli are highly reliable but not very detectable at a distance, while stimuli from the host's food are very detectable but generally not very reliable in indicating host presence. One solution to this problem is to learn to link highly detectable stimuli to reliable but not very detectable stimuli. Ample knowledge is available on how associative learning aids foraging parasitoids in the location of suitable microhabitats. However, in this paper we report on another solution to the reliability-detectability problem and present evidence for an essential, but as yet overlooked, aspect of Drosophila parasitoid ecology. For the first time it is shown that a parasitoid of Drosophila larvae spies on the communication system of adult Drosophila flies to locate potential host sites: naive parasitoids strongly respond to a volatile aggregation pheromone that is deposited in the oviposition site by recently mated female flies. Thus, the parasitoids resort to using highly detectable information from a host stage different from the one under attack (i.e. infochemical detour). The function and ecological implications of these findings are discussed.
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  • 123
    ISSN: 1432-1939
    Keywords: Hymenoptera ; Ectopasitoids ; Oviposition ; Interspecific competition ; Host recognition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Bruchidius atrolineatus (Pic) is a tropical beetle (Coleoptera Bruchidae) that develops during the larval and pupal stages in the seeds of a legume Vigna unguiculata (Walp). Two species of Hymenoptera, Dinarmus basalis (Rond) and Eupelmus vuilleti (Craw), solitary ectoparasitoids of the larvae and pupae of B. atrolineatus, were introduced successively in the presence of their hosts, varying the interval between the two introductions. When D. basalis females were introduced 24 h, 3 days or 7 days after E. vuilleti, multiparasitism was low. The females had low fecundity, and their eggs were not distributed randomly over the different available hosts. When E. vuilleti females were introduced second, they oviposited on the different hosts availabe and did not avoid multiparasitism. The presence of hosts already parasitised by D. basalis increased the reproduction of E. vuilleti, and the fecundity of the females was higher than in control batches with E. vuilleti alone. E. vuilleti seems capable of detecting the ovipositor shafts drilled by the D. basalis females, and by introducing its own ovipositors killing the D. basalis eggs or larvae. When interspecific competition was occurring the number of E. vuilleti adults emerging from the seeds was no different from that observed in control batches with E. vuilleti alone, and there were always fewer D. basalis adults than in control batches (D. basalis alone). This interspecific competition reduces the influence of the two parasitoids in the biological control of bruchid populations.
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  • 124
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    Biochemical genetics 29 (1991), S. 593-600 
    ISSN: 1573-4927
    Keywords: glycerol-3-phosphate dehydrogenase ; bees ; wasps ; isozymes ; Hymenoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Glycerol-3-phosphate dehydrogenase (G-3-PDH) isozymes were investigated in several bee and wasp species to verify if variations detected in G-3-PDH-2 isozymes are closely related to the age and activity of adult workers in the nest or hive of social species. In the solitary, the semisocial, and one social bee species, no phenotypic variations were detected for G-3-PDH-2 isozymes, and this was also the case for all wasp species investigated which were characterized as social. These results allow us to suggest that the variation detected in G-3-PDH-2 isozymes is a phenomenon closely related not only to adult age and activity in the hive, but also to a gradual acquisition of the ability to fly, which is not present in newly emerged worker meliponids in particular.
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  • 125
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    Astrophysics and space science 216 (1994), S. 55-65 
    ISSN: 1572-946X
    Keywords: Stars: Hot, Wolf-Rayet ; Turbulence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The quantification of stochastic substructures seen propagating away from the centers of emission lines of Wolf-Rayet (WR) stars is extended using the powerful, objective technique of wavelet analysis. Results for the substructures in one WR star so far show that the scaling laws between (a) flux and velocity dispersion and (b) lifetime and flux, combined with (c) their mass spectrum, strongly support the hypothesis that we are seeing the high mass tail-end distribution of full-scale supersonic compressible turbulence in the winds. This turbulence sets in beyond a critical radius from the star and shows remarkable similarity to the hierarchy of cloudlets seen in giant molecular clouds and other components of the ISM. The velocity dispersion is larger on average for substructures (interpreted as density enhanced turbulent eddies) propagating towards or away from the observer, suggesting that the turbulence is anisotropic. This is not surprising, since the most likely force which drives the windand the ensuing turbulence alike, radiation pressure, is directed outwards in all directions from the star. It is likely that a similar kind of turbulence prevails in the winds of all hot stars, of which those of WR stars are the most extreme. The consequences of clumping in winds are numerous. One of the most important is the necessary reduction in the estimate of the mass-loss rates compared to smooth outflow models.
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  • 126
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    Astrophysics and space science 221 (1994), S. 371-382 
    ISSN: 1572-946X
    Keywords: Wavelets ; Stars: Hot, Wolf-Rayet ; Turbulence
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    Topics: Physics
    Notes: Abstract A wavelet analysis technique is developed and used to study variable spectral features on top of broad emission lines in Wolf-Rayet stars. A decomposition of the signal in discrete structures allows one to look for scaling laws. Results from the study of two Wolf-Rayet stars suggest we are seeing the upper tail-end of a scaled distribution. This provides a test for turbulence models, and sets new constraints on theoretical wind models.
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  • 127
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    Journal of chemical ecology 10 (1984), S. 1425-1433 
    ISSN: 1573-1561
    Keywords: Social wasp ; Polistes exclamans ; Polistes fuscatus ; Vespidae ; Hymenoptera ; venom ; alarm pheromone ; alarm behavior
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The venoms ofPolistes exclamans andP. fuscatus elicit alarm behavior and attract attacking wasps. The response is not species specific, for both hetero- and conspecific venoms elicit similar responses in both species. A test in a wind tunnel provided no support for the hypothesis that alarmed wasps release an alarm pheromone on the nest.
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  • 128
    ISSN: 1573-1561
    Keywords: Kairomone ; 2-acylcyclohexane-1,3-diones ; ovipositionEphestia kuehniella Zeller [syn.Anagasta kuehniella (Zeller)] ; Lepidoptera ; Pyralidae ; Nemeritis canenscens (Grav.) [syn.Venturia canescens (Grav.)] ; Hymenoptera ; Ichneumonidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The relative activities of sixteen 2-acylcyclohexane-1,3-diones from the larval mandibular glands ofEphestia (=Anagasta) kuehniella Zeller in causing the parasiteNemeritis (=Venturia) canescens (Grav.) to make oviposition movements are reported.
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  • 129
    ISSN: 1573-1561
    Keywords: Leptopilinaheterotoma ; Hymenoptera ; Eucoilidae ; Saccharomyces cerevisiae ; host-habitat searching ; chemoreception ; fermentation products ; ethanol ; ethyl acetate ; acetaldehyde
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Chemical stimuli play an important role in the process of searching for a host habitat by parasitic wasps. Volatile compounds originating from host habitats and/or hosts are the cues that enable such a location.Leptopilina heterotoma, a larval parasite ofDrosophila, is attracted to the food of its host, baker's yeast. Analysis of the fermentation products of baker's yeast, using a mass spectrometer, and olfactometer studies indicate that three fermentation products of this yeast, the main component of the host habitat in our laboratory, attractL. heterotoma: ethanol (5%), ethyl acetate (10−2, 10−3%), and acetaldehyde (1%). A combination of these three compounds, however, cannot compete with baker's yeast in attracting the parasites. Thus other factors, such as different compounds, concentrations, and/or combinations, also, play a role and remain to be tested.Leptopilina heterotoma does not use host-related olfactory cues in long-distance habitat location as it cannot distinguish between host habitat and host habitat with hosts.
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  • 130
    ISSN: 1573-1561
    Keywords: Pine sawflies ; Neodiprion spp. ; Hymenoptera ; Diprionidae ; electroantennogram ; sex pheromone ; isomers ; jack pine ; Pinus banksiana ; diprionol ; 3,7-dimethylpentadecan-2-ol ; acetate ; propionate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Several species of monophagous jack pine sawflies (Hymenoptera: Diprionidae) were tested in the field and by electroantennograms (EAG) for activity toward the optical isomers of a pine sawfly sex pheromone, the acetate and propionate esters of 3,7-dimethylpentadecan-2-ol.Neodiprion rugifrons andNeodiprion dubiosus were attracted to a mixture of the propionate esters of the 2S,3R,7R and 2S,3R,7S isomers, whereasNeodiprion swainei was attracted to the 2S,3S,7S propionate isomer. Samples containing the 2S,3R,7S propionate isomer elicited the strongest EAG responses in these three species andNeodiprion nigroscutum. The 2S,3S,7S propionate isomer was equally active (EAG) in the case ofN. swainei.
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  • 131
    ISSN: 1573-1561
    Keywords: Enantiomer discrimination ; male patrolling ; odor marking ; Hymenoptera ; Apoidea ; Andrena wilkella ; bee ; EAG ; spiroacetal ; absolute configuration ; 2,8-dimethyl-1,7-dioxaspiro[5.5]undecane
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Diastereomers of the spiroacetal, 2,8-dimethyl-1,7-dioxaspiro [5.5]undecane, represent main components of the cephalic secretion from males of the solitary bee,Andrena wilkella. The major compound proved to be of high enantiomeric purity, showing (2S,6R,8S) configuration. Only the naturally occurring enantiomer attracted patrolling males in the field; its antipode was behaviorally inactive and in a racemic mixture did not inhibit response. The (E,Z) diastereomers were also found to be almost inactive. EAG studies gave the same result as the behavioral tests. The biological function of the spiroacetal is discussed in view of the evolution of the mating behavior inA. wilkella.
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  • 132
    ISSN: 1573-1561
    Keywords: Internally branched alkenes ; internal alkenes ; cuticular hydrocarbons ; Nothomyrmecia macrops ; Hymenoptera ; Formicidae ; ants ; gas chromatography ; mass spectrometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Internally mono- and dimethyl branched, internal alkenes, which constitute most of the cuticular hydrocarbon present on workers of the primitive Australian antNothomyrmecia macrops Clark, have been identified by gas chromatography-mass spectrometry. They are the first such alkenes reported from insects. Also present are alkanes with similar carbon skeletons. The hydrocarbon patterns of three separateNothomyrmecia colonies were very similar.
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  • 133
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    Journal of chemical ecology 16 (1990), S. 1207-1219 
    ISSN: 1573-1561
    Keywords: Ants ; Dacetini ; Daceton armigerum ; Hymenoptera ; Formicidae ; poison gland ; pygidial gland ; sternal gland ; mandibular gland ; trail communication ; alarm communication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Contrary to previous assumptions,Daceton armigerum, the largest ant in the myrmicine tribe Dacetini, employs trail communication. We identified two anatomical sources of trail pheromones: Trails drawn with poison gland contents can last for more than seven days. Trails drawn with the newly discovered sternal glands (in the VIth and VIIth abdominal sternites) are effective but relatively short-lived. In addition, our bioassays revealed that the contents of the mandibular glands elicit alarm behavior, and secretions from the pygidial gland release attraction. When tested with artificial poison gland trails from seven other myrmicine species,Daceton did not exhibit trail following behavior. We confirmed, however, previous findings thatAtta respond toDaceton poison gland trails andSolenopsis followDaceton Dufour's gland trails.
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  • 134
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    Journal of chemical ecology 17 (1991), S. 557-566 
    ISSN: 1573-1561
    Keywords: Bee ; Nomada lathburiana ; nest parasite ; cephalic secretion ; terpenoids ; Hymenoptera ; Anthophoridae ; cuckoo
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A series of new sesquiterpene ketones and norsesquiterpene ketones could be identified from the cephalic secretion of females of the cuckoo bee,Nomada lathburiana (K.). The major component proved to be 2,6,10-trimethylundeca-(5E)-2,5,9-trien-4-one. Large amounts of high-boiling-point straight-chain hydrocarbons serve as solvents for the volatile, unstable ketones.
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  • 135
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    Journal of chemical ecology 16 (1990), S. 2009-2017 
    ISSN: 1573-1561
    Keywords: Apanteles kariyai ; Hymenoptera ; Braconidae ; Acantholeucania loreyi ; Pseudaletia separata ; Lepidoptera ; Noctuidae ; 2,5-dialkyltet-rahydrofuran ; arrestant ; allelochemical ; antimone ; kairomone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Females of the larval parasitoidApanteles kariyai (Watanabe) (Hymenoptera: Braconidae) are arrested on fecal pellets ofAcantholeucania loreyi (Duponchel) (Lepidoptera: Noctuidae) larvae. Upon subsequent antennal contact with anA. loreyi larva, females sting it with their ovipositor. However, such stinging did not result in any offspring. The allelochemical involved in feces has been identified and is identical to a kairomone of the hostPseudaletia separata (Lepidoptera: Noctuidae). In contrast toA. loreyi, P. separata is a suitable host forA. kariyai, and oviposition inP. separata results in offspring production. The allelochemical mediating the interaction betweenA. loreyi andA. kariyai is discussed in the context of current allelochemical terminology.
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  • 136
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    Journal of chemical ecology 16 (1990), S. 2135-2143 
    ISSN: 1573-1561
    Keywords: Philanthus triangulum ; Hymenoptera ; Sphecidae ; Philanthinae ; beewolf ; (Z)-11-eicosen-1-ol ; 10-nonadecen-2-one ; nonadecenal ; eicosenal ; pheromone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Males of the European and African beewolf,Philanthus triangulum, possess a sex specific mandibular gland secretion that is used for marking plant stems in mating territories. The secretion is composed of 90% (Z)-11-eicosen-1-ol plus small amounts of 10-nonadecen-2-one, nonadecenal, octadecanoic and octadecenoic acids, and eicosenal. The chemistry of this secretion differs markedly from the secretions of North AmericanPhilanthus, which consist of a larger number of components that possess different chemical functionalities and are more volatile. We postulate that the chemical differences betweenP. triangulum and its New World relatives reflect phylogenetic differences plus a possible reduced necessity for species isolating mechanisms inP. triangulum.
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  • 137
    ISSN: 1573-1561
    Keywords: Nestmate discrimination ; polygynous ants ; cuticular hydrocarbons ; multivariate analysis ; aggression ; prairie ants ; class distinction ; Hymenoptera ; Formicidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Polygynous ant species often monopolize patchily distributed habitats and tolerate neighboring conspecifics while aggressively attacking other ant species. We determined that internest aggression occurs in the polygynous ant,Formica montana. We report for the first time the identities of cuticular hydrocarbons ofF. montana and present results of their possible role in nestmate recognition. Cuticular hydrocarbons contribute differentially to class discrimination, certain hydrocarbons being more class distinct.
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  • 138
    ISSN: 1573-1561
    Keywords: Polistes metricus ; Hymenoptera ; Vespidae ; social wasps ; cuticular hydrocarbons ; nestmate recognition ; nest pedicel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In eight replicate laboratory tests wherePolistes metricus adults were allowed to choose between their own nest, a second nest, and neither nest, they selected their own nest 66% of the observed time. When the surface hydrocarbons had been extracted from the nests, the wasps chose their own nest only 8% of the time, but after the hydrocarbons were reapplied to the surface of the respective nests, they selected their own nest 47% of the time. These changes are significant. The cuticular lipids were analyzed from individualP. metricus adult females collected from 13 colonies. Surface lipids were recovered from the paper and pedicels of their nests. Eighteen hydrocarbons were identified in these lipid fractions. The major components of the wasp cuticular lipids weren-heptacosane,n-nonacosane, methylhentriacontane, and methyltritriacontane. Factor analysis revealed that extracts of pedicels are all similar in composition, while cuticle and paper extracts vary, sometimes similarly according to colony identity.
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  • 139
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    Journal of chemical ecology 16 (1990), S. 3067-3089 
    ISSN: 1573-1561
    Keywords: Semiochemicals ; kairomones ; parasitoid behavior ; parasitoid manipulation ; foraging environment ; Heliothis zea ; Lepidoptera ; Noctuidae ; Microplitis croceipes ; Hymenoptera ; Braconidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Allelochemicals are known to serve important roles at all steps in the host-searching sequence of parasitoids. We discuss the various roles of these allelochemics and the type of information needed to develop their use in pest control, which to date has been very limited. Rapid advancements are being made with respect to airborne chemicals and longer-range foraging behavior. Moreover, recent discoveries have shown that genetic diversity in parasitoid populations and phenotypic plasticity of individuals, together with their physiological state, often result in substantial variations in the response to chemical cues. Successful application of semiochemical-parasitoid systems will require management of these intrinsic parasitoid variables as well as management of the foraging environment. We illustrate emerging technology for such an application. For the immediate future, the development of this technology will allow us to: (1) define the genetic and phenotypic foraging profiles important to consistent and efficient parasitoid foraging, and (2) establish the proper propagation and release procedures and monitoring bioassays necessary to ensure appropriate behavioral and physiological qualities of released organisms. For the long term, we envision technology for comprehensively manipulating the pest/crop environment in ways that would provide foraging stimuli and other needs important to retention and efficiency of parasitoids.
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  • 140
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    Journal of chemical ecology 16 (1990), S. 2429-2439 
    ISSN: 1573-1561
    Keywords: Cucumis sativus ; ferulic acid ; split root ; phosphorus ; potassium ; water ; net uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Since distribution of allelopathic compounds in soils is highly variable, injurious effects by such compounds should be related to the frequency of contact with roots. Experiments were conducted to determine how P, K, and water uptake of cucumber seedlings were affected as the fraction of roots in contact with ferulic acid (FA) was increased. Seedlings were grown in Hoagland's nutrient solution for 14 days and then transferred to 0.5 mM CaSO4 solution for 24 hr before being placed into a split-root culture system. The containers in the system were filled with 0.5 mM concentrations of KH2PO4 and CaSO4 or 0.5 mM concentrations of KH2PO4, CaSO4, and ferulic acid (FA). Net uptake of P by seedlings (milligrams per seedling) decreased in a curvilinear (concave) manner as the fraction of the roots in contact with FA increased. Net uptake of K (milligrams per seedling) and water (milliliters per seedling) by seedlings decreased linearly as the fraction of the roots in contact with FA increased. Net uptake of P, K, and water by seedlings was reduced 57, 75, and 29%, respectively, when the whole root system was exposed to FA. Net P and K uptake of roots (milligrams per gram root fresh weight) not in contact with FA decreased in a linear and curvilinear (convex) manner, respectively, as the fraction of roots in contact with FA increased. Net P and K uptake of roots in contact with ferulic acid increased in a linear and curvilinear (convex) manner, respectively. Net water uptake of roots (milliliters per gram root fresh weight) not in contact with FA increased in a curvilinear (concave) manner as the frequency of the roots in contact with FA increased. Net water uptake of roots in contact with FA did not show a trend. Transpiration (milliliters per square centimeter) was reduced in a linear manner as the fraction of roots in contact with FA increased. A very slight compensation by roots not in contact with FA for roots in contact with FA was observed for net water uptake rates. No compensation for P and K uptake rates was observed.
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  • 141
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    Journal of chemical ecology 17 (1991), S. 1811-1819 
    ISSN: 1573-1561
    Keywords: Atta cephalotes ; Hymenoptera ; Formicidae ; attine fungus ; fungal performance ; condensed tannin ; hydrolyzable tannin ; polyphenol oxidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The leaf-cutting antAtta cephalotes is a generalist herbivore of the neotropics and collects leaf material to cultivate a fungus. It appears that this fungus, a Basidiomycete, is responsible for the ability of the ants to utilize most of the available woody plant species. Tannins and other phenolics are ubiquitous secondary chemicals in woody plants, and Basidiomycete fungi produce enzymes, such as polyphenol oxidase, that are capable of polymerizing and inactivating the phenolics. This study evaluates the effects of a condensed and a hydrolyzable tannin on the activity of polyphenoi oxidase and the growth of the fungus. I hypothesized that low concentrations of tannin would not inhibit polyphenol oxidase activity but high concentrations would inhibit the enzyme. Consequently, I predicted that only high concentrations of tannin would inhibit fungal growth. Laboratory assays with the fungus indicated that hydrolyzable tannin (tannic acid) and condensed tannin (quebracho tannin) differ in the mechanism of inhibition. Tannic acid does not inhibit polyphenol oxidase activity but does inhibit fungal growth. Quebracho tannin, however, inhibits both polyphenol oxidase activity and fungal growth. As predicted, both tannic acid and quebracho tannin primarily inhibit the fungus at high concentrations.
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  • 142
    ISSN: 1573-1561
    Keywords: Atta laevigata ; Hymenoptera ; Formicidae ; territorial pheromone ; agonistic behavior ; Dufour gland
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The workers of the leaf-cutting antAtta laevigata were found to mark a territory around their nest and along trunk trails. Elsewhere, we reported that the territorial mark had orientation and agonistic functions. The presence of this mark induced an alarm behavior in intruder workers and stimulated the residents' aggressiveness. Of the parts of the body tested, only the extracts from gaster or Dufour gland were able to induce the same agonistic behavior. The compoundsn-heptadecane, (Z)-9-nonadecene, 8,11-nonadecadiene, and (Z)-9-tricosene, secreted by Dufour gland were identified on foraging trails in the field as components of the territorial odor.
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  • 143
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    Journal of chemical ecology 18 (1992), S. 209-221 
    ISSN: 1573-1561
    Keywords: Trillium ; ant dispersal ; Hymenoptera ; Formicidae ; elaiosomes ; lipids ; diglycerides ; triglycerides ; oleic acid ; linoleic acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract This study was designed to compare the chemistry of elaiosomes of three sympatric species ofTrillium to discover if there are correlations between chemistry and dispersal rates by ants. We quantified the amount of proteins and neutral lipids and qualitatively analyzed the fatty acids occurring in triglyceride, diglyceride, monoglyceride, and free fatty acid fractions.T. grandiflorum had the highest lipid concentration per milligram of protein and the highest total lipid per elaiosome, followed byT. erectum and then byT. undulatum. Oleic acid (18∶1) was abundant in all lipid fractions of each species. This fatty acid, which is responsible for corpse-carrying behavior in some ants, probably causes ants to pick up diaspores. Linoleic acid (18∶2) is relatively abundant inT. erectum andT. grandiflorum but not inT. undulatum and may cause ants that have picked up diaspores to move (carry) those diaspores back to the nest. Total elaiosome mass and fatty acid composition appear to explain whyT. erectum is dispersed most rapidly and why ants that have picked up elaiosomes move moreT. grandiflorum thanT. undulatum diaspores.
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  • 144
    ISSN: 1573-1561
    Keywords: Pheromone ; 3,5-dimethyl-6-(methylethyl)-3,4,5,6-tetrahydropyran-2-one ; enantiomer ; parasitoid ; Macrocentrus grandii ; Hymenoptera ; Braconidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In a previous study we reported identification of (3R*,5S*,6R*)-3,5-dimethyl-6-(methylethyl)-3,4,5,6-tetrahydropyran-2-one as a component of the pheromone ofMacrocentrus grandii Goidanich. The lactone was present in male and female wasps, and laboratory and field bioassays demonstrated that both sources of the lactone elicit flight initiation, upwind anemotaxis, and casting in male wasps. In the present study, the synthetic (3R,5S,6R)- and (3S,5R,6S)-lactone enantiomers (RSR andSRS, respectively) were bioassayed for biological activity. In wind tunnel studies theSRS enantiomer elicited flight initiation, upwind anemotaxis, and casting by male wasps comparable to lactone derived from male and female wasps. Flight response to theRSR enantiomer averaged 14 percent of theSRS enantiomer. No specific ratio of the stereoisomers was found more attractive than theSRS enantiomer alone. Field studies demonstrated theSRS enantiomer was active alone in attracting male wasps. When paired with (Z)-4-tridecenal (a previously identified female-derived sex pheromone), theSRS enantiomer yielded a synergistic response comparable to (Z)-4-tridecenal plus female-derived lactone.
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  • 145
    ISSN: 1573-1561
    Keywords: Phenylalkenals ; Leptogenys spp ; Pogonomyrmex rugosus ; Hymenoptera ; Formicidae ; 2-phenylpropenal ; 2-phenyl-2-butenal ; 2,5-dimethyl-3-(1-methyl) butylpyrazine ; 2,5-dimethyl-3-isopentylpyrazine ; 2,5-dimethyl-3-isopentenyl-6-isopentylpyrazine ; 4-methyl-3-heptanone ; 5-methyl-3-hexanone ; Maillard reaction ; benzaldehyde ; chemoreceptors ; defensive allomones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Cephalic extracts of two unrelated species of ants,Leptogenys processionalis andPogonomyrmex rugosus, have been found to contain 2-phenylpropenal and 2-phenyl-2-butenal, while two other species related to the first,L. chinensis andL. kitteli, lacked either.L. kitteli also produced a tetrasubstituted pyrazine found previously only in two New Zealand ants in the genusMesoponera. The chemical reactivity of the phenylalkenals suggests their function in repelling attack by predators.
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  • 146
    ISSN: 1573-1561
    Keywords: Hymenoptera ; Braconidae ; Lepidoptera ; Pieridae ; Cruciferae ; tritrophic interactions ; foraging behavior ; host-habitat location ; herbivoreinduced synomones ; flight chamber ; infochemicals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Recently parasitoids were hypothesized to encounter a reliability-detectability problem relating to chemical stimuli from the first and second trophic level, when searching for hosts. The relative role of infochemicals originating from the host,Pieris brassicae (second trophic level), and its food plant, cabbage (first trophic level), have been investigated with respect to long-range host location by the larval parasitoidCotesia glomerata. Flight-chamber dual choice tests showed that uninfested cabbage plants are least attractive to female wasps. Host larvae and their feces were more attractive than clean plants but far less attractive than artificially damaged and herbivore-damaged plants. The plant-host complex, with host larvae actively feeding on the plant, was the most attractive odor source for the parasitoids. The data indicate that one of the solutionsC. glomerata uses to solve the reliability-detectability problem is to respond to infochemicals that are emitted from herbivore-damaged plants. Whether these infochemicals are herbivore-induced synomones that are produced by the plant remains to be demonstrated. Infochemicals emitted by the herbivore or its by-products are of little importance in the foraging behavior ofC. glomerata.
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  • 147
    ISSN: 1573-1561
    Keywords: Philanthus crabroniformis ; Philanthus barbatus ; Philanthus pulcher ; Hymenoptera ; Sphecidae ; beewolf ; mandibular glands ; pheromones ; semiochemicals ; mass spectrometry ; infrared spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The composition of the territorial marking pheromones from mandibular glands of males of the beewolvesPhilanthus crabroniformis, P. barbatus, andP. pulcher have been determined. The structures of the components were elucidated by gas chromatography-mass spectrometry and gas chromatography-Fourier transform infrared spectroscopy. The major compound ofP. crabroniformis is isopropyl tetradecanoate, with somewhat lesser amounts of 2-tridecanone, 3-methyl-3-butenyl tetradecanoate, and 92∶8 (Z)∶(E)-11-eicosen-1-ol. The major compounds ofP. barbatus are ethyl tetradecanoate and hexadecanal, which are present in approximately a 60∶40 ratio. These two compounds comprise over 95% of the neutral lipids. Also present in lesser amounts are ethyl dodecanoate, tetradecanal, hexadecan-1-ol, a Δ x -octadecen-1-ol, and octadecan-1-ol. The major compounds ofP. pulcher are ethyl (Z)-7-hexadecenoate and geranylgeraniol acetate, which comprise nearly 90% of the neutral lipid fraction, with smaller amounts of tetradecanal, pentadecanal, and ethyl hexadecanoate; trace amounts of Δ x hexadecenal, hexadecanal, and octadecanal are also present.
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  • 148
    ISSN: 1573-1561
    Keywords: scanning electron microscopy ; CP/MAS [13C]NMR ; Hymenoptera ; Vespidae ; social wasps ; Polistes metricus ; nest paper ; nest pedicel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The ultrastructure and chemical composition of paper and pedicel from nests ofPolistes metricus that were constructed in the laboratory from known building material were compared to paper and pedicel from nests constructed in the field. Scanning electron micrographs showed the addition of a gluelike secretion from the wasp to the construction material. Solid-state [13C]NMR, elemental analyses, and amino acid analyses indicate that this secretion is a silklike protein with serine, glycine, alanine, and proline comprising 65–73% of the identified residues.
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  • 149
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    Journal of chemical ecology 18 (1992), S. 1901-1912 
    ISSN: 1573-1561
    Keywords: Parasitoid ; pheromone ; bioassay ; wind-tunnel ; Hymenoptera ; Braconidae ; Macrocentrus grandii ; Lepidoptera ; Pyralidae ; Ostrinia nubil-alis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A multicomponent sex pheromone inMacrocentms grandii Goidanich (Hymenoptera: Braconidae) was demonstrated using wind-tunnel and field bioassays. In wind-tunnel bioassays, three Florisii fractions from female wasps (hexane, 5%, and 50% ether in hexane) and one from male wasps (50% ether in hexane) were attractive to males. The hexane and 5% ether in hexane fractions each elicited similar male behavioral responses. These included upwind anemotaxis, casting, landing on the source, wing fanning, and mating attempts between males. The 50% ether in hexane fraction, whether male- or female-derived, initiated a strong flight response by males but few landings on the source. In addition, the 50% ether in hexane fraction was found to synergize strongly the hexane fraction. All females tested in the wind tunnel gave no responses to male- or female-derived extracts. Field tests generally supported the wind-tunnel results, although no field attraction was observed for the 5% ether in hexane fraction.
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  • 150
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    Journal of chemical ecology 20 (1994), S. 2307-2321 
    ISSN: 1573-1561
    Keywords: Polistes metricus ; Hymenoptera ; Vespidae ; cuticular hydrocarbons ; discriminant analysis ; nestmate recognition ; social wasps
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The cuticular lipids ofPolistes metricus queens, workers and males from seven laboratory-maintained colonies were extracted and analyzed by combined gas chromatography-mass spectrometry. Males had higher proportions of alkenes (20.5%) in their cuticular lipids than did queens (2.3%) or workers (7.7%). Discriminant analyses of the cuticular lipid profiles of the adult wasps showed that males group separately from females. Additional analyses showed that queens group with their respective workers by colony and that queens group even more closely with males by colony. The most distinct groupings occurred with workers only by colony and with males only by colony. Stepwise discriminant analyses showed that each type of grouping was dependent upon a different combination of cuticular lipids.
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  • 151
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    Journal of chemical ecology 20 (1994), S. 2437-2453 
    ISSN: 1573-1561
    Keywords: Varroa jacobsoni ; Acari ; Varroidae ; mite ; Apis mellifera ; Hymenoptera ; Apidae ; honeybee ; chemoreception ; host selection ; cuticle ; hydrocarbons ; alkanes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The ectoparasitic miteVarroa jacobsoni invades worker brood cells of the honeybeeApis mellifera during the last 20 hr before the cells are sealed with a wax cap. Cuticle extracts of 8-day-old worker honeybee larvae occupying such brood cells have an arrestment effect on the mite. The mites run for prolonged periods on the extract, systematically returning onto the stimulus after touching the borders of the treated area. Mites increase walking speed and path straightness in response to increasing doses of a nonpolar fraction of the cuticle extract. Saturated straight-chain odd-numbered C19–C29 hydrocarbons were identified by thin-layer argentation chromatography and gas chromatography-mass spectrometry as the most active constituents, with branched alkanes also contributing to the arrestment effect of this active fraction. Analysis of the behavior responses to syntheticn-alkanes indicate that the response is probably based on a synergism between the different alkane components of the fraction rather than to an individual compound.
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  • 152
    ISSN: 1573-1561
    Keywords: Herbivory ; host preference ; host selection ; oviposition ; phenolic glucosides ; willow ; Salicaceae ; Salix ; galling sawfly ; Hymenoptera ; Tenthredinidae ; Euura amerinae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The effects of phenolic glucosides on the oviposition behavior ofEuura amerinae L. (Hymenoptera: Tenthredinidae) were tested in multiple oviposition experiments using different shoot length categories ofSalix pentandra L. (with different amounts of phenolic glucosides) and in experiments with pure phenolic glucosides (salidroside, arbutin, salicin, 90% salicortin, 90% 2′-O-acetylsalicortin) or composite total fractions of phenolic glucosides from three willow species (S. pentandra, S. myrsinifolia Salisb.,S. triandra L.). This was the first time that the effects of pure phenolic glucosides on the oviposition behavior of sawfly species were tested. Total fraction of phenolic glucosides fromS. pentandra and its main individual glucoside, 2′-O-acetyl-salicortin, stimulated the strongest ovipositional behavior inE. amerinae. The results show clearly that females ofE. amerinae can recognize and choose their host willow,S. pentandra, on the basis of phenolic glucosides. Moreover, they are probably able to use phenolic glucosides as a cue in shoot selection within host-plant individuals.
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  • 153
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    Journal of chemical ecology 18 (1992), S. 271-282 
    ISSN: 1573-1561
    Keywords: Plant-insect interaction ; Pinus sylvestris ; Neodiprion sertifer ; Diprion pini ; Hymenoptera ; Diprionidae ; insect performance ; flavonoids ; taxifolin glucoside ; resin acids
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Responses of sawfly larvae (Hymenoptera, Diprionidae) to the flavonoid taxifolin glucoside in their host plant were studied in a laboratory experiment. Larvae ofNeodiprion sertifer andDiprion pini were raised from egg hatch to cocoon spinning on two Scots pine (Pinus sylvestris) chemotypes, one without needle taxifolin glucoside (−) and the other containing 2–4% taxifolin glucoside (+). The (+) chemotype had somewhat lower concentrations of needle terpenoids (resin acids) than the (−) chemotype. Current-year needles had higher taxifolin glucoside concentrations than mature needles. There were no differences in survival or body size betweenN. sertifer larvae that fed on the (+) chemotype and those that fed on the (−) chemotype. FemaleD. pini larvae raised on (+) needles developed 6% more slowly than larvae fed (−) needles. The results from this study are contrary to earlier findings showing that flavonoid glucosides have strong negative effects on insect performance. Possible explanations for the different outcomes are discussed.
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  • 154
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    Journal of chemical ecology 19 (1993), S. 1315-1321 
    ISSN: 1573-1561
    Keywords: Dufour's gland ; poison gland ; myrmicine ant ; alkanes ; alkenes ; anabaseine ; anabasine ; alkaloids ; Hymenoptera ; Formicidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The Cape harvester ant,Messor capensis (Mayr), is widespread in the more arid regions of southern Africa, where it forms trails many meters long and harvests considerable quantities of seeds. The poison gland contains primarily the alkaloid, anabaseine, with minor amounts of the related alkaloid, anabasine, and an unidentified compound. The Dufour's gland contains predominantly alkanes and alkenes of carbon chain length 12–23.n-Pentadecane is the major component, with lesser amounts ofn-pentadecene,n-tridecane,n-heptadecane,n-tetradecane,n-heneicosene, andn-tricosene. The dienes,n-heneicosadiene andn-tricosadiene are rather unusual components of the Dufour's gland of ants.
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  • 155
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    Journal of chemical ecology 6 (1980), S. 467-472 
    ISSN: 1573-1561
    Keywords: Pheromone ; caste ; ant ; Hymenoptera ; Formicidae ; Tetramorium caespitum ; 4-methyl-3-hexanol ; 4-methyl-3-hexanone
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The heads of maleT. caespitum contain 4-methyl-3-hexanol (1.7 μg, only the erythro isomer(s) detected) and 4-methyl-3-hexanone (0.8 μg). The heads of alate females contain 0.1 μg of each compound, whereas only the alcohol (0.1 ⧎g) was found in the heads of workers. Both compounds act as attractants for the workers and their possible functions are discussed.
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  • 156
    ISSN: 1573-1561
    Keywords: Colletes spp. ; bees ; Hymenoptera ; Colletidae ; Dufour's gland secretion ; nest cell lining
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The liquid secretion of the Dufour's gland in mated females comprises a mixture of macrocyclic lactones, straight chain mono- and dicarboxylic acids, together with trace amounts of di- and trihydroxy monocarboxylic acids and a series ofn-alkanes. Polymerization of the liquid to form the membranous nest cell lining, which also contains alanine and glutamic acid as major constituents, may be mediated by an enzyme from the thoracic salivary gland and voided via the mouth. The composition and structure of the cell linings are similar to those of Wigglesworth's “cuticulin.”
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  • 157
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    Journal of chemical ecology 6 (1980), S. 827-835 
    ISSN: 1573-1561
    Keywords: Pyrazines ; 2,5-dimethyl-3-isopentylpyrazine ; marking volatiles ; mandibular gland ; philanthine wasp ; nyssonine wasp ; premating behavior ; Hymenoptera ; Sphecidae
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Males of several sphecid wasps apply volatile secretion on specific sites, perches. The odor is supposed to act in premating behavior as an attracting pheromone. There are strong indications that the scenting material is produced by the mandibular glands. One philanthine species,Philanthus triangulum, and three nyssonine ones,Argogorytes fargei, A. mystaceus, andNysson spinosus, the latter cleptoparasite onArgogorytes wasps, have been analyzed by gas chromatography-mass spectrometry. The major compound in the mandibular gland secretion of the four species was tentatively identified as 2,5-dimethyl-3-isopentylpyrazine. A few other pyrazines not yet identified were also found. Preliminary tests withP. triangulum show that alkylpyrazines influence male behavior.
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  • 158
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    Journal of chemical ecology 6 (1980), S. 883-893 
    ISSN: 1573-1561
    Keywords: Pachycondyla (= Termitopone) laevigata ; Hymenoptera ; Formicidae ; chemical communication ; termite predation ; pygidial gland
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Termite predation by the ponerine antPachycondyla (= Termitopone) laevigata is regulated by a recruitment trail pheromone which originates from the pygidial gland and not, as previously assumed, from the hindgut. The pygidial gland opens between the 6th and 7th abdominal terga and is associated with a distinct cuticular structure which obviously serves as a glandular applicator.
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  • 159
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    Journal of chemical ecology 7 (1981), S. 909-917 
    ISSN: 1573-1561
    Keywords: Trichogramma pretiosum ; Hymenoptera ; Trichogrammatidae ; biological control ; kairomone ; Heliothis zea ; Lepidoptera ; Noctuidae ; host density
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Trichogramma pretiosum Riley females exhibit success-motivated searching after oviposition. The stimulatory effect of contact with host eggs makes host-egg density an important factor in determining the appropriate strategy for behavioral manipulation, using kairomones, that simulate host seeking, in biological control programs. Host eggs can be used, in conjunction with kairomones or by themselves, to improve the performance of these important beneficial insects.
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  • 160
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    Journal of chemical ecology 8 (1982), S. 285-300 
    ISSN: 1573-1561
    Keywords: Monomorium spp. ; Hymenoptera ; Formicidae 2,5-dialkylpyrrolidines ; ant venom alkaloids ; methoxymercuration-demercuration ; chemotaxonomy
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A comparative analysis of the venomous alkaloids produced by ant species in the subgenusMonomorium of the genusMonomorium has been undertaken. All species produce mixtures of unsymmetricaltrans-2,5-dialkylpyrrolidines, but the proportions of the constituents may vary considerably between species. All alkaloids contain both C6 and C9 side chains which are present as C9-saturated. C6-monounsaturated, and both C6-and C9-monounsaturated dialkylpyrrolidines. The structure of 2-(1-hex-5-enyl)-5-(1-non-8-enyl)pyrrolidine, a previously undescribed alkaloid, was proved by unambiguous synthesis after the location of the double bonds was established by the methoxymercuration-demercuration followed by mass spectrometry. The possible chemotaxonomic significance of the mixtures of venomous alkaloids produced by these species ofMonomorium is discussed.
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  • 161
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    Journal of chemical ecology 8 (1982), S. 867-871 
    ISSN: 1573-1561
    Keywords: Apis mellifera ; Hymenoptera ; Apidae ; 2-heptanone ; isopentyl acetate ; citral ; geraniol ; hoarding
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Hoarding experiments were conducted with honeybees (Apis mellifera L.) in cages containing comb treated with either 2-heptanone, isopentyl acetate, citral, or geraniol. 2-Heptanone increased hoarding rates; isopentyl acetate decreased hoarding rates; citral and geraniol had no observed effect.
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  • 162
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    Journal of chemical ecology 8 (1982), S. 1035-1042 
    ISSN: 1573-1561
    Keywords: Dufour's gland ; volatile components ; Nemeritis canescens(Grav.) ; hydrocarbons ; Hymenoptera ; Ichneumonidae ; oviposition
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The Dufour's gland of the parasitic waspNemeritis (= Venturia) canescens (Grav.) was shown by gas chromatography and mass spectrometry to contain a mixture of C21, C23, and C25 saturated and monounsaturated hydrocarbons. The main component (62%) was (Z)-10-tricosene. The biological activity of the components is discussed.
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  • 163
    ISSN: 1573-1561
    Keywords: Argentine ant ; Iridomyrmex humilis (Mayr) ; Hymenoptera ; Formicidae ; trail-following bioassay ; (Z)-9-hexadecenal ; geometric isomer ; analogues ; choice tests
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In laboratory trail-following bioassays of Argentine ant workers,Iridomyrmex humilis (Mayr), the geometric isomer, (E)-9-hexadecenal, of the trail pheromone component (Z)-9-hexadecenal elicited insignificant trail following as did the potentially more stable formate analogs, (Z)-7-tetradecenyl formate, (E)-7-tetradecenyl formate, and tetradecyl formate. Further, in direct choice tests, workers showed no preference for gaster extract trails (0.002 ant equiv/cm) over trails of (Z)-9-hexadecenal (0.2 ng/cm). Moreover, a 10-fold increase in synthetic trail concentration to 2.0 ng/cm caused (Z)-9-hexadecenal trails to be significantly preferred over gaster extract trails by trail-following ants.
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  • 164
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    Journal of chemical ecology 9 (1983), S. 57-65 
    ISSN: 1573-1561
    Keywords: Honeybee ; Apis mellifera ; alarm pheromone ; acetate ; alcohol ; Hymenoptera ; Apidae ; sting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Twelve compounds identified from honeybee,Apis mellifera L., sting extracts were evaluated in a standardized laboratory test for their effectiveness in eliciting an alarm response from caged worker honeybees. Two-1-decanol and phenol-were judged ineffective as alarm pheromones. The other ten-1-butanol, isopentyl acetate, isopentyl alcohol, 1-hexanol, 2-heptyl acetate, 2-heptanol, 1-octanol, 1-acetoxy-2-octene, 2-nonyl acetate, and 1-acetoxy-2-nonene-produced alarm responses of similar speed and intensity. Three non-sting-derived compounds-β-ionone, methyl benzoate, andtrans-cinnamaldehyde—caused weak or no responses, indicating that the responses were not simply a reaction to concentrated odoriferous substances.
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  • 165
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    Journal of chemical ecology 9 (1983), S. 105-111 
    ISSN: 1573-1561
    Keywords: Pogonomyrmex badius ; Hymenoptera ; Formicidae ; oleic acid ; social context ; midden ; pheromone ; harvester ant ; necrophoric
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The response of the southern harvester ant,Pogonomyrmex badius, to oleic acid was found to depend on social context. Social context was specified as the number of ants engaging in each of five categories of behavior. When a large percentage of the colony is doing midden work or nest maintenance, papers treated with oleic acid are taken to the midden, as previously reported. However, when a large percentage of the colony is foraging or convening, treated papers are taken into the nest as if they were food items.
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  • 166
    ISSN: 1573-1561
    Keywords: Larch sawfly ; Pristiphora erichsonii (Hartig) ; Hymenoptera ; Tenthredinidae ; feeding behavior ; nutritional indices ; abietic acid ; dehydroabietic acid ; neoabietic acid ; isopimaric acid ; sandaracopimaric acid ; resin acids
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Diterpene resin acids significantly affect consumption rates, feeding efficiencies, and growth rates of the larch sawfly,Pristiphora erichsonii (Hartig) when topically applied to their natural food, tamarackLarix laricina (DuRoi) K. Koch. Abietic acid, neoabietic acid, dehydroabietic acid, and isopimaric acid significantly reduced consumption rates, feeding efficiencies, and growth rates. Sandaracopimaric acid reduced growth and efficiency but did not influence consumption rate. Two-way analysis of variance indicates a significant interaction between chemical and concentration for growth rate, feeding efficiency, and consumption rate. This interaction indicates that increasing chemical concentrations do not influence the larch sawfly in a uniform manner, supporting the concept of concentration-dependent biological activity of allelochemics.
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  • 167
    ISSN: 1573-1561
    Keywords: Xylocopa hirsutissima ; Vespa orientalis ; Camponotus ; Hymenoptera ; Xylocopidae ; Vespidae ; Formicidae ; pheromone ; allomone ; chemical preparation ; cis-3,6-dimethyltetrahydro-2-pyrone ; 6-n-undecyltetrahydro-2-pyrone ; 6-n-pentyl-5,6-dihydro-2-pyrone ; lactones
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Simple preparations ofcis-3,6-dimethyltetrahydro-2-pyrone, VII,6-n-undecyltetrahydro-2-pyrone, XVIIb, and 6-n-pentyl-5,6-dihydro-2-pyrone, XVIa, have been achieved. Products VII and XVIIb, respectively, are the major constituent of the pheromonal blend of a carpenter bee (Xylocopa hirsutissima) and the pheromone of the queens of the Oriental hornet (Vespa orientalis). The lactone XVIa is a suspected defensive allomone in two species of formicine ants of the genusCamponotus. All three compounds have been prepared from dehydroacetic acid, I, a cheap and industrially available starting material.
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  • 168
    ISSN: 1573-4927
    Keywords: esterases ; Megachile rotundata ; Hymenoptera ; allozymes ; isozymes
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract This study describes the biochemical characterization and genetic variation of cytosolic esterases in the alfalfa leafcutting bee,Megachile rotundata (Fab.). Esterase isozymes were separated by nondenaturing polyacrylamide gel electrophoresis and isoelectric focusing and characterized by inhibition with eserine sulfate, EDTA, paraoxon, andp-hydroxymercuribenzoate. Based on inhibition patterns and substrate specificity, there are major differences between adults and immature forms and more subtle differences between male and female adults. M. rotundata esterases are largely organophosphate sensitive and the two major adult allozymes were highly variable within the population examined. Differences in esterase expression between life stages with respect to niche and the occurrence of diploid males are discussed.
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  • 169
    ISSN: 1573-4927
    Keywords: esterases ; Megachile rotundata ; Hymenoptera ; allozymes ; isozymes
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract This study describes the biochemical characterization and genetic variation of cytosolic esterases in the alfalfa leafcutting bee,Megachile rotundata (Fab.). Esterase isozymes were separated by nondenaturing polyacrylamide gel electrophoresis and isoelectric focusing and characterized by inhibition with eserine sulfate, EDTA, paraoxon, andp-hydroxymercuribenzoate. Based on inhibition patterns and substrate specificity, there are major differences between adults and immature forms and more subtle differences between male and female adults. M. rotundata esterases are largely organophosphate sensitive and the two major adult allozymes were highly variable within the population examined. Differences in esterase expression between life stages with respect to niche and the occurrence of diploid males are discussed.
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    Biochemical genetics 30 (1992), S. 443-453 
    ISSN: 1573-4927
    Keywords: heterozygosity ; allozymes ; Hymenoptera ; Bombus ; Psithyrus
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Allozyme variation at an average of 37.3 loci was assessed in queens of 16Bombus and 2Psithyrus bumble bee species from North America. The mean expected heterozygosity $$(\bar H)$$ for theBombus species was 0.008±0.006 (95% confidence limits) and that for thePsithyrus was 0.007±0.007. These levels are significantly lower than found in other Hymenoptera but are comparable to those found in previous studies of bumble bees based on far fewer loci. Neutral mutation and random genetic drift can account for the observed variation, but this implies a very small effective population size for species of bumble bees.
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  • 171
    ISSN: 1573-4927
    Keywords: glycerol-3-phosphate dehydrogenase ; social bees ; wasp ; isozymes ; Hymenoptera
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In only 1 bee species(Tetragona clavipes) of 24 sampled in 145 colonies (0.69%) did we detect the presence of more than one allele for glycerol-3-phosphate dehydrogenase (EC 1.1.1.8), an enzyme that is involved in flight. In 34 colonies containing 9 wasp species, 5 colonies of only 2 species(Polybia paulista andP. sericea) showed variation in larval G-3-PDH (14.7%). The small amount of variation observed for theG-3-PDH-1 locus in the bee and wasp species analyzed in the present study agrees with that reported for the G-3-PDH system in other insects.
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  • 172
    ISSN: 1432-1351
    Keywords: Comparative colour vision ; Opponent processes ; Colour computation ; Hymenoptera ; Colour discrimination behaviour
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Behavioural tests were carried out with 9 hymenopteran insect species, which ranked certain sets of coloured stimuli according to their subjective similarity to a previously memorized stimulus. Kendall's τ coefficient is employed for the analysis of correlation between these similarity rankings and the colour distance rankings predicted by various models of neural colour computation. The models are based on the measured spectral sensitivities of photoreceptor colour types and use a variety of simple colour coding systems to derive hypothetical colour distances. The correlation between the predictions of the models and the behavioural results serves as a measure for the likelihood of existence of a colour coding system. In all species, the similarity rankings can be best explained by assuming that colour is coded on a perceptual level by two colour opponent mechanisms. Brightness differences are ignored, indicating that an intensity-coding sub-system is not used in colour discrimination by the insects investigated. The weighting factors of the colour opponent mechanisms differ between species in detail, but not in the principles involved. It is thus possible to employ a standard measure of perceptual colour distance (colour hexagon distance) to predict the capacities of colour discrimination adequately in all the tested insects.
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    The visual computer 9 (1993), S. 200-212 
    ISSN: 1432-2315
    Keywords: Gaseous animation ; Turbulence ; Spectral synthesis ; Natural phenomena simulation ; Texture generation ; Time-varying texture
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    Topics: Computer Science
    Notes: Abstract This paper presents a new spectral synthesis method, motivated by the spectral turbulence theory, for visual modeling and the realistic and computer-effective animation of turbulent gaseous motion in 2-D and 3-D, which avoids the computational costs of direct simulation. Animation of gases is achieved through a phase shift in the frequency domain according to Kolmogorov's exponential law. The parameters of the turbulence model are intuitive, enabling animaters and designers to become familiar with them quickly. Owing to the method's computational effectiveness, an interactive, (quasi-)real-time, parallelized version, which provides the fast feedack needed to easily adjust the model's parameters, could be implemented.
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    Theoretical chemistry accounts 63 (1983), S. 323-338 
    ISSN: 1432-2234
    Keywords: Dynamic systems ; Chaotic chemical reactions ; Kinetic logic ; Turbulence ; Belousov-Zhabotinskii reaction
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    Topics: Chemistry and Pharmacology
    Notes: Abstract Earlier approaches to the analysis of chemical dynamic systems using kinetic logic are refined to deal more effectively with systems having the two or more feedback circuits required for chaos. The essential kinetic features of such a system can be represented by a directed graph (called aninfluence diagram) in which the vertices represent the internal species and the directed edges represent kinetic relationships between the internal species. Influence diagrams characteristic of chaotic chemical systems have the following additional features: (1) They are connected; (2) Each vertex has at least one edge directed towards it and one edge directed away from it; (3) There is at least one vertex, called a turbulent vertex, with at least two edges directed towards it. From such an influence diagram a state transition diagram representing the qualitative dynamics of the system can be obtained using the following 4-step procedure: (1) A logical relationship is assigned at each turbulent vertex; (2) A local truth table is generated for each circuit in the influence diagram; (3) The local truth tables are combined to give a global truth table using the logical relationships at the turbulent vertices; (4) The global truth table is used to determine the corresponding state transition diagram using previously described methods. This refined procedure leads to a more restricted set of influence diagrams having the interlocking cycle flow topology required for chaos than the procedure described earlier. Systems with 3 internal species are examined in detail using the refined procedure. All systems with 3 dynamic variables shown in the simulation studies of Rössler to give chaotic dynamics correspond to influence diagrams which give inter-locking cycle (chaotic) flow topologies by the refined procedure. In addition, two models for the Belousov-Zhabotinskii reaction are examined using the refined procedure. The results are potentially informative concerning possible mechanisms for the limitation of the accumulation of autocatalytically produced HBrO2 (one of the internal species) during the course of this reaction.
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    Potato research 23 (1980), S. 371-375 
    ISSN: 1871-4528
    Keywords: nitrogen ; phosphorus ; potassium ; calcium ; sodium ; nitrate ; sulphate ; micronutrients
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The specific gravity and dry matter content of 193 tuber samples (cultivars: Arran Banner, Spunta, Up-to-Date, Cara) from crops grown at Kokkinochoria, the major potato growing area of Cyprus, were related to each other as follows: Dry matter (%)=−269.59+268.24×specific gravity. This regression accounted for 82.4% of the variation; the fiducial limits (P〈0.05) for single determinations of specific gravity were±1.54 percentage units. The mineral contents of the tubers were similar to those reported in other countries.
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  • 176
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    Potato research 33 (1990), S. 13-21 
    ISSN: 1871-4528
    Keywords: hormones ; media ; phosphorus ; rooting depth ; solar radiation ; temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary To expand potato production in developing countries using cuttings as a source of good quality planting material, requires simple low cost methods to root and establish them. Experiments at a warm tropical site in the Philippines, to determine appropriate methods, showed that simple media ranging from fine sand to clay subsoil mixed with rice hulls enabled rooting which was not improved by hormones. Nitrogen rich media, such as volcanic soil or compost with additional P, were best for developing cuttings into strong transplants but there were no major differences in root and shoot development from cuttings differing in size and age. Tuberizations was favored by increasing the number of nodes buried in the media. Low solar radiation of 7 MJ/m2/day enabled high cutting survival up to root initiation, after which higher radiation supported larger root and shoot production.
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  • 177
    ISSN: 1573-9171
    Keywords: EPR ; radical ; fluorine ; conformation ; phosphorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract EPR spectra of radical adducts of phosphonyl radicals with 2-hydroperfluoro-4-methyl- and 4,4-dimethyl-2-pentene have been studied. The molecular mechanics method has been used to determine the preferred conformation of the (CF3)2CF-CF-HCF3P(O)(OMe)2 radical. The eclipsed conformation of the C–P bond and 2p z -orbital of an unpaired electron is stabilized due to steric factor and hyperconjugation.
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  • 178
    ISSN: 1615-6102
    Keywords: Hymenoptera ; Olfactory sensilla ; Sensillum placodeum ; Trichogen cell doubling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The oval pore plates (approx. 17 μm long) are separated from the antennal cuticle by a furrow, the inner wall of which is flexible. The thin perforated plates are strengthened by an encircling and a middle ledge, the latter of which branches into about 100 almost parallel rims. Each pore plate is innervated by about 20 sense cells. The dendrites fork into numerous branches occupying the outer receptor lymph cavity below the perforated plate. Each pore plate is associated with one thecogen cell, two trichogen cells, one tormogen cell and one “envelope cell 4”. A so-called “additional cell” surrounds the sensillum in the imaginal stage. The envelope cells in the later of the two pupal stages examined, have reached an arrangement which immediately precedes the secretion of the cuticulin layer. The surface of the duplicate trichogen cells is almost equal in area to the completed perforated plate. A dendritic sheath, entirely reduced in the imago, protrudes into the exuvial space, where it encloses a single dendrite. In the younger pupal stage the “Sensillenanlage” forms a crater, whereby envelope cell 4 overtops the other envelope cells. The distal ends of the trichogen cells are divided into several appendages that form the bottom of the “crater”.
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  • 179
    ISSN: 1573-5125
    Keywords: Ems estuary ; phosphorus ; iron ; fluorescence ; aluminium ; adsorption ; suspended matter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In winter 1992/1993, a persistent local maximum in fluorescence, dissolved iron, dissolved aluminium and dissolved inorganic phosphate was found, upstream of the turbidity maximum in the freshwater zone of the Ems estuary (The Netherlands — Federal Republic Germany; western Europe). Upstream of this local maximum values ranged from 6 to 9 rel. units fluorescence, 0.9 to 2.4 μmol dm−3 iron, 0.5 to 0.7 μmol dm−3 aluminium and 0.6 to 2.3 μmol dm−3 dissolved inorganic phosphate. Within the maximum peak values of 24 rel. units fluorescence, 5.8 μmol dm−3 iron, 1.4 μmol dm−3 aluminium and 8.3 μmol dm−3 dissolved inorganic phosphate were observed. Downstream, fluorescence (indicator of dissolved organic carbon) showed conservative mixing with sea water, whereas dissolved iron, aluminium and dissolved inorganic phosphate did not. Dissolved aluminium and iron were quickly removed from solution to reach values of ∼100 nmol dm−3 aluminium and ∼0.3 μmol·dm−3 Fe at salinities of approximately 7 PSU. Further seaward iron concentrations gradually decreased to levels below 0.04 μmol dm−3. Dissolved aluminium first decreased to ∼20 nmol dm−3 at 29 PSU and increased again to concentrations of 30–44 nmol dm−3 at higher salinities. Dissolved inorganic phosphate, however, first decreased to upstream concentrations before reaching a secondary peak in the mid-estuarine reaches. At salinities 〉25 PSU dissolved inorganic phosphate mixed conservatively with sea water. It is hypothesized that adsorption-desorption equilibria are responsible for the local maximum values of fluorescence (DOC), iron, aluminium and dissolved inorganic phosphate. The similarity between the observed curves suggests a common underlying process, possibly related to the adjustment of new equilibria between suspended matter of marine and riverine origin.
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  • 180
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    Applied mathematics and mechanics 15 (1994), S. 1047-1053 
    ISSN: 1573-2754
    Keywords: Turbulence ; LES (large eddy simulation) ; turbulence model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Mathematics , Physics
    Notes: Abstract In this paper the database obtained from LES is used to examine the algebraic turbulence model in Demuren and Rodi’s work. The results show that the prediction of normal Reynolds stresses and turbulence energy by means of turbulence modeling is better than that of shear Reynolds stresses. The comparison shows the LES method can be used to examine turbulence modelling.
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  • 181
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    Aquatic ecology 24 (1990), S. 69-89 
    ISSN: 1573-5125
    Keywords: model ; eutrophication ; phosphorus ; P/C ratio ; lake ecosystem
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A dynamic, deterministic model is presented to simulate the phosphorus cycle and plankton growth in the shallow, hypertrophic Loosdrecht Lakes (The Netherlands) before and after restoration measures. Besides inorganic phosphorus (SRP) in both the surface water and the interstitial water, the model comprises three algal groups, zooplankton, fish, detritus, zoobenthos and upper sediment (all modelled both in carbon and in phosphorus). Within the model system, the phosphorus cycle is completely closed. Carbon and phosphorus are described independently, so that the dynamics of the P/C ratios can be modelled. Sediment processes are described in a simplified form. Simulated values are largely within the range of observed ones. The detrital fraction of the seston (=phytoplankton+detritus) varies from 50–60% in summer to about 90% in winter. SRP in the surface water is very low during most of the year. Sensitivity for external phosphorus input is larger for algal and detrital P than for algal and detrital C and chlorophyll-a. So the P/C ratio of the seston decreases following restoration measures, as is observed in the lakes, while the much higher P/C ratios of zooplankton and fish remain constant. Phosphorus mobilisation from the sediment decreases with decreasing external input. Adaptation of the model system to the reduced loading takes place within about two years. Sources of uncertainty in the model include the limited knowledge on selective grazing as well as on mortality and mineralisation processes.
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  • 182
    ISSN: 1573-5176
    Keywords: seaweed ; Agardhiella ; carrageenan ; phosphorus ; cultivation ; growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Gas liquid chromatography, chemical analyses, and infrared and13C-NMR spectroscopies indicated that phycocolloids extracted fromAgardhiella subulata had a dominant ι-carrageenan feature with less deviant ι-carrageenan and υ-carrageenan. The presence of methylated galactose and a small contamination by xylose were registered. Unattached plants were cultivated for 4 weeks in tanks receiving seawater enriched with 53.5 µM nitrate and 0 to 20 µM phosphate (Pi) week−1. The growth was phosphorus (P)-limited up to a tissue P content of 0.14 ± 0.03% dry weight. Maximal specific growth rate and carrageenan content were observed with enrichments of 6 µM Pi and 3 µM Pi, respectively. Hence carrageenan production was promoted in the range of 3–6 µM Pi. Further Pi enrichment was useless. This phenomenon, observed with P nutrition, is comparable to the ‘Neish effect’ in nitrogen nutrition studies.
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  • 183
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    International journal of salt lake research 3 (1994), S. 159-173 
    ISSN: 1573-8590
    Keywords: phosphorus ; orthophosphate ; phosphomolybdenum blue ; salt effect ; hypersaline ; saline ; lakes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geography
    Notes: Abstract Standard methods for the determination of phosphorus as phosphate ion are now well established for fresh and marine waters. In highly saline waters, however, salt effects due to ionic strength, or to particular ions present, may result in method interferences. Three methods of analysis of phosphate based on the formation of phosphomolybdenum blue complexes have been evaluated here for hypersaline waters. Stannous chloride reduction in aqueous media exhibits a substantial salt effect and its use is not recommended. Stannous chloride reduction following extraction into non aqueous solvents shows a significant salt effect (up to 30 per cent) in solutions of salinity 〉100 g L−1. Dilution of hypersaline waters to below this salinity may overcome the salt effect but the method suffers from other disadvantages involving resource constraints and health and safety considerations. Ascorbic acid reduction, catalysed by antimony (III) ions, appears to offer the most promise for hypersaline waters. Turbidity in samples having high salinity (〉 100 g L−1) and high phosphorus concentrations (〉 500 μg P L−1) changes the spectral characteristics of solutions but linear calibration curves still result for concentrations in the range 400 to 1,000 μg P L−1. The occurrence of turbidity is also affected by the ionic composition of hypersaline waters since solutions made from sea salt give different results to those made from sodium chloride. Dilution of samples, to give salinities less than 100 g L−1 prior to reduction is recommended to avoid turbidity. The salt effect in these lower salinity waters is less than 3 per cent up to 100 g L−1.
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    Journal of scientific computing 9 (1994), S. 369-403 
    ISSN: 1573-7691
    Keywords: Turbulence ; transport model ; Reynolds stress ; realizability ; second-order closure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract The realizability of Reynolds stress models in homogeneous turbulence is critically assessed from a theoretical standpoint. It is proven that a well known second-order closure model formulated using the strong realizability constraints of Schumann (1977) and Lumley (1978) is, in fact, not a realizable model. The problem arises from the failure to properly satisfy the necessary positive second time derivative constraint when a principal Reynolds stress vanishes-a flaw that becomes apparent when the nonanalytic terms in the model are made single-valued as required on physical grounds. More importantly, arguments are advanced which suggest that it is impossible to identically satisfy the strong from of realizability in any version of the present generation of second-order closures. On the other hand, models properly formulated to satisfy the weak form of realizability—wherein states of one or two component turbulence are made inaccessible in finite time via the imposition of a positive first derivative condition—are found to be realizable. However, unlike the simpler and more commonly used second-order closures, these models can be ill-behaved near the extreme limits of realizable turbulence due to the way that higher-degree nonlinearities are often unnecessarily introduced to satisfy realizability. Illustrative computations of homogeneous shear flow are presented to demonstrate these points which can have important implications for turbulence modeling.
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  • 185
    ISSN: 1573-7691
    Keywords: Turbulence ; probability distributions ; temperature fluctuations ; vorticity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract A phenomenological theory of single-point probability distributions in turbulence is presented. Expressions for the probability distribution functions are derived and analyzed for a decaying passive scalar, temperature fluctuations in Bénard convection and vorticity fluctuations in both stationary and decaying homogeneous, isotropic turbulence. The predictions of the theory are compared with the results of physical and numerical experiments.
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    Evolutionary ecology 6 (1992), S. 312-330 
    ISSN: 1573-8477
    Keywords: genetic models ; inbreeding depression ; mating cost ; Hymenoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Existing genetic models of the evolution of sibmating behaviour in diploids incorporate inbreeding depression in terms of reduced fecundity of consanguineous mating pairs rather than reduced survival or fecundity of the progeny of such matings. Here we derive a model to correct this deficiency and extend the model to haplodiploids where differential effects of inbreeding in males and females is a crucial consideration. Our analyses indicate that sibmating can readily evolve in both diploids and haplodiploids in which male mating costs and inbreeding depression are reasonably low, provided there is some mechanism to permit sibmating such as siblings being reared in nests or other forms of aggregation. Our analyses also indicate that once sibmating invades, it typically will go to fixation, although sib-/randommating polymorphisms can persist in both diploids and haplodiploids if male mating costs are close to zero and inbreeding depression reduces survival by around one-third. The conditions favouring sibmating are slightly more restrictive in haplodiploids than in diploids. In light of this we may ask why we see intense sibmating in many haplodiploids such as parasitic wasps, fig wasps, ants, bark beetles and mites, and only rarely in diploid animals. The common factor could be certain kinds of aggregation behaviour that are a prerequisite for sibmating in the absence of kin recognition. Another possibility is that inbreeding depression is likely to be more severe in diploids than in haplodiploids because deleterious recessives are purged from haplodiploid populations when expressed by haploid males. Thus, lower levels of inbreeding depression might be one important reason why sibmating appears to arise more frequently in haplodiploids than diploids. Phylogenetic analysis of groups, such as bark beetles and mites, exhibiting both diploid and haplodiploid populations may be useful in elucidating the relative importance of gregarious behaviour and haplodiploidy in facilitating sibmating systems.
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    Plant and soil 126 (1990), S. 115-119 
    ISSN: 1573-5036
    Keywords: inorganic P ; organic P ; P/Fe ; P/Mn ratios ; phosphorus ; rice ; silicon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A pot experiment was conducted to measure the effect of silicon on phosphorus uptake and on the growth of rice at different P levels. Rice (Oryza sativa L. cv. Akebono) was cultured in Kimura B nutrient solution without and with silicon (1.66 mM Si) and with three phosphorus levels (0.014 mM P, low; 0.21 mM, medium; and 0.70 mM, high). Shoot dry weight with Si (+Si) in solution increased with increasing P level, while shoot weight without Si (−Si) was maximum at 0.21 mM P, suggesting that +Si raised the optimum P level for rice. +Si increased shoot weight more when P was low or high than when P was medium. The concentration and amount of inorganic P in shoots increased with increasing P level. +Si did not significantly decrease P uptake by rice at 0.014 mM P, however, uptake at 0.21 and 0.70 mM P was 27 and 30 percent less than uptake with −Si, respectively. In −Si with 0.21 and 0.70 mM P, inorganic P in shoots was more than double the concentration in shoots grown in +Si solutions. The Si concentration in shoots decreased slightly with increasing P level, although Si uptake was not significantly affected by P. +Si decreased the uptake of Fe and Mn by an average of 20 and 50 percent, respectively, thus P/Mn and P/Fe ratios increased in the shoot when P was low. From the results above, the beneficial effect of Si on the growth of rice was clearly shown when P was low or high. This effect may have resulted from decreased Mn and Fe uptake, and thus increased P availability within P deficient plants, or from reduced P uptake when P was high.
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  • 188
    ISSN: 1573-5036
    Keywords: aluminium ; aluminium toxicity ; Leucaena yield ; lime ; phosphorus ; phosphorus uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The effects of lime and P addition on the amounts of soil extractable P and Al, and on the growth of the tropical legume Leucaena leucocephala were investigated in a factorial experiment under controlled climate conditions using 4 (Koronivia, Nadroloulou, Batiri, and Seqaqa) highly-weathered, acid (pH initially 3.9 to 4.9) soils from Fiji. Resin-extractable P increased with lime addition and then decreased above pH 5.5, whereas M KCl-extractable Al decreased to undetectable levels at or above pH 5.2. Plant growth was usually adversely affected at low and high pH, even in the presence of added P. The pH (in M KCl) at which maximum growth occurred in the 4 soils varied from approximately 4.4 to 5.2; values somewhat lower than those reported in the literature. Changes in dry matter yield with increasing soil pH were strongly influenced by P status and a positive lime × P interaction was obtained with 3 of the 4 soils. Above pH 5.2, liming decreased the yield of both tops and roots, for reasons which are discussed in part II. The data obtained for extractable soil P and plant P concentrations indicate that P deficiency is a major problem on these soils.
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  • 189
    ISSN: 1573-5036
    Keywords: aluminium ; aluminium toxicity ; aluminium-induced P deficiency ; chemical composition ; Leucaena ; lime ; Lolium perenne L ; perennial ryegrass ; phosphorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The effects of lime and P on the chemical composition of the tropical legume Leucaena leucocephala were studied in a controlled climate laboratory experiment using 4 (Koronivia, Nadroloulou, Batiri, and Seqaqa) highly-weathered, acid soils from Fiji. For all soils, changes in the concentration of P in the Leucaena tops followed trends similar to the yield response curve, i.e., the concentration of P was highest at the soil pH at which maximum growth occurred. The concentration of Al in plant tops increased on either side of the pH of maximum growth, but Al uptake by the whole plant (tops plus roots) declined steadily with increasing pH. Although complete major (except P) and minor nutrients were added regularly, there was variation in the uptake of nutrients with pH. Poor growth at low pH values was attributed to an Al-induced P deficiency within the plant and at high pH to a soil P deficiency and, to a smaller extent, to the increased concentration of Al in the plant tops.
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  • 190
    ISSN: 1573-5036
    Keywords: disturbance ; fertilizer ; nitrogen ; nutrient enrichment ; phosphorus ; secondary succession ; species richness
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Effects of annual additions of mineral N and P (100 kg ha−1) on plant species composition and annual aboveground net primary production (ANPP) were investigated during the first three years following disturbance in a semi-arid ecosystem. Additions of N reduced richness of perennial plant species during years 2 and 3, while P reduced the number of perennial species only in year 3. From year 1 to year 2, annual and biennial species richness declined in all treatments while ANPP of annual species increased greatly. Added N increased ANPP of annual species while it decreased ANPP of most perennial species relative to the unfertilized control treatment. Community similarities were higher for the control and native vegetation than for other pairs of treatments using both species presence and plant production data. Nitrogen additions have retarded but not completely arrested secondary succession in this system.
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  • 191
    ISSN: 1573-5036
    Keywords: eucalypt ; foliar analysis ; legume ; nitrogen ; phosphorus ; plant nutrients ; plant analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The sensitivity of tissue nutrient concentrations to changes in plant age and the supply of P and N was compared between leaves and associated twigs in two forest species. In a young regrowth stand, tissues were sampled on three occasions from the mid-crown position of karri (Eucalyptus diversicolor F. Muell.) and Bossiaea laidlawiana Tovey and Morris, a major understorey legume. Leaves and twigs were also sampled from young plants of B. laidlawiana growing in a mature eucalypt stand to which P treatments had been applied. Nitrogen application increased N concentrations in twigs of karri and B. laidlawiana, but not in leaves. Phosphorus application increased P concentrations in both leaves and twigs of karri but the average increases were proportionally greater in twigs (65%) than in leaves (36%). Over the sampling period, P concentrations in leaves declined, while those in twigs were relatively stable. In B. laidlawiana, P supply also had a larger effect on P concentrations in twigs than in leaves. Addition of 200 kg P ha−1 increased average P concentrations in twigs by 109% in the regrowth stand and by 215% in the mature stand while the corresponding increases in leaves were only 11% and 27%. Concentrations of other nutrients in both species were also affected by N and P application, the most notable being a decline in the concentrations of the minor nutrients, Zn and Cu, with increased P supply. The increased N concentrations in twigs of karri, and the increased P concentrations in tissues of both species, were associated with responses of karri to added N and P, and of B. laidlawiana to added P. This indicates that tissue concentrations of N and P were generally below critical concentrations where N and P were not applied. The results show that for these species twigs may be a better tissue than leaves for diagnosing deficiencies or predicting N and P requirements. The ratio of P concentrations in twigs to P concentrations in leaves also increased with added P. It is suggested that this ratio may be a useful index if it reduces the variability caused by sampling position within the crown or genetic differences between plants.
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  • 192
    ISSN: 1573-5036
    Keywords: ammonium ; labile organic P ; nitrate ; N mineralization ; phosphorus ; Plantago major L. ssp. pleiosperma ; soil nutrient availability ; soil nutrient pools ; spatial variation ; temporal variation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract As part of a research project on the variation in life-history characteristics within a population of Plantago major L. ssp. pleiosperma, seasonal and spatial variability in the availability of macronutrients (N, P, and K) were examined on a small scale in the 0–25 cm soil depth at a primary beach plain site, embanked since 1966. On the basis of distinct differences, among other things, in plant biomass, an a priori division into three different types of microhabitat occurring in a mosaic distribution pattern was made: an overall low-lying area (subsite 1) with slightly elevated patches of 0.5 to 1.5 m in diameter (subsite 2) and rather large patches, 20 to 40 m in diameter, of sea buckthorn shrubs, with small and relatively open spots (subsite 3) in the transitional zone from lower area into scrub. All three subsite types were studied within a total area of approximately 2000 m2. Three methods of analysis were applied: an inventory survey (sampling once at the start of the growing season), an analysis of the seasonal variation (sampling at approximately monthly intervals during the period April-November), and an assessment of nitrogen mineralization potentials in the laboratory (sampling once at the beginning of the growing season). All three procedures clearly demonstrated the occurrence of differences in the availability of nutrients over very short distances, i.e. a pronounced spatial variability among subsites. Particularly the availability of N and P appeared to have increased at the subsites 2 and 3, when compared to subsite 1. This small-scale differentiation in soil properties has occurred in an essentially homogeneous parent material (e.g. in texture and carbonate content) over a period of about 20 years. Besides a spatial variability, statistically significant temporal fluctuations were observed in the availability of N, P, and K. Relative fluctuations of mineral N (as indicated by the range/mean ratio) were especially large at the subsites 2 and 3.
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    Biochemical genetics 29 (1991), S. 593-600 
    ISSN: 1573-4927
    Keywords: glycerol-3-phosphate dehydrogenase ; bees ; wasps ; isozymes ; Hymenoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Glycerol-3-phosphate dehydrogenase (G-3-PDH) isozymes were investigated in several bee and wasp species to verify if variations detected in G-3-PDH-2 isozymes are closely related to the age and activity of adult workers in the nest or hive of social species. In the solitary, the semisocial, and one social bee species, no phenotypic variations were detected for G-3-PDH-2 isozymes, and this was also the case for all wasp species investigated which were characterized as social. These results allow us to suggest that the variation detected in G-3-PDH-2 isozymes is a phenomenon closely related not only to adult age and activity in the hive, but also to a gradual acquisition of the ability to fly, which is not present in newly emerged worker meliponids in particular.
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    Mathematical geology 5 (1973), S. 127-148 
    ISSN: 1573-8868
    Keywords: granitic rocks ; phosphorus ; range number ; comparative trend analysis ; information-theory statistics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Mathematics
    Notes: Abstract One hundred and three samples of granitic rock taken systematically from the Andean part of Colombia reveal that the observed variation in phosphorus content reflects the variation observed for the wholerock chemical composition. This relationship was established using a form of trend analysis termed COMTRENA and information-theory statistics.
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  • 195
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    Plant systematics and evolution 137 (1981), S. 229-240 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Orchidaceae ; Cephalanthera longifolia ; Cistaceae ; Cistus salviifolius ; Hymenoptera ; Halictus ; Flower biology and ecology ; pollination ; pollen imitation ; floral mimicry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Solitary bees (Halictus sp.) were found to be the effective pollinators ofCephalanthera longifolia. In the same foraging flight the bees also visit flowers ofCistus salviifolius which has a similar colour pattern.Cephalanthera offers no reward to its pollinators, but orange papillae on its labellum successfully imitate pollen ofCistus. AsCephalanthera also attracts pollinators in the absence ofCistus, this is regarded as “facultative floral mimicry”.
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    Plant systematics and evolution 137 (1981), S. 241-258 
    ISSN: 1615-6110
    Keywords: Orchidaceae ; Ophrys ; Hymenoptera ; Apoidea ; Scoliidae ; Sphecidae ; solitary bees ; Pollination ; pseudocopulation ; isolating mechanisms ; plant mimicry ; Flora of southern Spain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An investigation of pseudocopulation behaviour in species ofOphrys from southern Spain confirms the close relationship betweenCampsoscolia ciliata (Scoliidae) andOphrys speculum, and betweenEucera nigrilabris (Apoidea) andOphrys tenthredinifera. It could be demonstrated thatEucera barbiventris is the pollinator ofOphrys scolopax subsp.scolopax, whereas other species ofEucera andTetralonia which are active at the same time show no interest at all for the flowers of this species. Special attention was paid to the forms of the taxonomically confusedOphrys fusca group:O. fusca s. str.,O. iricolor, O. omegaifera andO. atlantica. WhileO. fusca s. str. is widespread, small-flowered and has late anthesis,O. iricolor has very large flowers and early anthesis. Each of the four members ofO. fusca agg. in S. Spain is pollinated by a different bee, and selective experiments show that each of these four species of bees is specifically attracted only to one of theOphrys species:Andrena flavipes is the pollinator ofO. fusca s. str.,Colletes cunicularius infuscatus ofO. iricolor, Anthophora atroalba ofO. omegaifera, andChalicodoma parietina ofO. atlantica. These four pollinators belong to 4 different bee families (Andrenidae, Colletidae, Anthophoridae, Megachilidae). As this type of pollination represents a very effective pregamic isolation mechanism, these four taxa ofOphrys fusca agg., at least in southern Spain, behave and should be regarded as genuine species.
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    Plant systematics and evolution 173 (1990), S. 209-222 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Scrophulariaceae ; Monttea ; Hymenoptera ; Anthophoridae ; Centris ; Oil-flowers ; oil-bees ; Flora of Argentina
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Plant species that secrete oil as their primary floral reward are rare and sporadically found in the angiosperms. We report here thatMonttea, a genus previously unsuspected of being an oil-plant, produces lipids from trichome elaiophores on the inside of the lower (anterior) lip. The discovery of the production of oils by species of this S. American genus explains the occurrence of unusual dual-function collecting structures in ArgentineCentris (Hymenoptera: Anthophoridae) and explains the presence of oil-collecting bees in regions where oil-secreting flowers were previously thought to be absent. The behavior of these centridine pollinators onMonttea flowers parallels that of oil-collecting bees onDiascia (Scrophulariaceae) in S. Africa.
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  • 198
    Electronic Resource
    Electronic Resource
    Springer
    Plant systematics and evolution 177 (1991), S. 71-75 
    ISSN: 1615-6110
    Keywords: Malus ; Medicago sativa ; Salvia glutinosa ; Hymenoptera ; Apoidea ; Apis mellifera ; Bombus ; Floral constancy ; foraging ; pollination ; social behaviour
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Contrary to most other bee species honeybees are highly eusocial and hold extremely long-lived societies. Their all-season activities force them to use whatever plants available and prevent any specific adaptations — in the flowers, in honeybees, and in all competing bees. This flexible behaviour in flowers has been a precondition for perennial colony life. But as bees evade becoming contaminated by pollen their visits often do not result in pollination. Honeybee monocultures thus must be avoided by all means.
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  • 199
    Electronic Resource
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    Springer
    Plant systematics and evolution 193 (1994), S. 173-186 
    ISSN: 1615-6110
    Keywords: Rhamnaceae ; Frangula ; Diptera ; Coleoptera ; Hymenoptera ; Mecoptera ; Breeding system ; phenology ; pollination biology ; protandry ; reproductive success ; self-incompatibility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Various aspects of the reproductive biology of the perennial hermaphroditeFrangula alnus Mill. were studied in two populations located in the province of Cádiz, southern Spain. Flowering extends from the second week of May to early July. The small, whitegreenish, entomophilous flowers are incompletely protandrous and last 8–10 days, but pollen transfer takes place only on days 1–3. A very weak, pleasant odour along with nectar and pollen attract over 45 insect species, of which 21 are probable pollinators. These are mainlyDiptera but also includeHymenoptera and the unusual (as flower visitors)Mecoptera. Reproduction is exclusively sexual and strictly xenogamous, with pollen transfer depending solely on insect vectors. Although flower morphology and individual flower phenology do not fully prevent self-pollination, and geitonogamy can easily take place, the level of autogamy was negligible. Therefore, some self-incompatibility mechanism is operative in this species. Only 2.8% of open-pollinated flowers set fruit. At the flower level, fruit initiation was apparently limited by availability of cross-pollen, which in turn seemed influenced by the structure of the population. The seed/ovule ratio in ripe fruits was ca. 50%. Predispersal (maternal) reproductive success (percent ovules becoming filled seeds) was 1.42%. For mature individuals this corresponded to ca. 430 to 1560 potential offspring per year.
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  • 200
    ISSN: 1573-5036
    Keywords: crop rotations ; copper ; fertilizers ; iron ; manganese ; phosphorus ; potassium ; zinc
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A field experiment was carried out to study the effect of various crop rotations, of high yielding varieties of cereals, pulses, fodders, tubers and oilseeds, on the performance of the crops and the fertility status of the soil over two crop-rotation cycles. The yields of rice (Oryza saliva L.), potato (Solanum tuberosum L.) and onion (Allium cepa) crops were found to be decreasing. The yields of wheat (Triticum aestivum L.) and mustard (Brassica juncea coss), were not affected, while the yield of moong (Phaseolus aureus Roxb.) showed a tendency to increase. Rotations which included berseem (Trifolium alexandrinum) increased the organic carbon content of the soil and there was a slight lowering of the pH with the highest application of phosphatic fertilizer. The accumulation of available potassium was greater in the treatments where the highest amount of fertilizer was applied. The available nitrogen content of the soil increased with application of nitrogen and the balance sheet of nitrogen, phosphorus and potassium showed a positive trend. The continuous cropping of high yielding varieties showed a reduction in the available zinc and iron status of the soil, whereas available manganese and copper increased. The available micronutrients, except manganese, did not correlate significantly with soil pH.
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