ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Lepidoptera  (66)
  • Zea mays  (45)
  • Springer  (111)
  • American Meteorological Society
  • Oxford University Press
  • Periodicals Archive Online (PAO)
  • 1995-1999
  • 1990-1994  (111)
  • 1935-1939
  • 1994  (111)
Collection
Publisher
  • Springer  (111)
  • American Meteorological Society
  • Oxford University Press
  • Periodicals Archive Online (PAO)
  • Wiley-Blackwell  (4)
Years
  • 1995-1999
  • 1990-1994  (111)
  • 1935-1939
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 71 (1994), S. 185-192 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Pyralidae ; Indianmeal moth ; semiochemicals ; attraction ; oviposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Substrates contaminated by wandering fifth instar larvae ofPlodia interpunctella (Hübner) (Lepidoptera: Pyralidae) elicit oviposition by conspecific female moths, and larval rearing diet enhances oviposition and also induces upwind flight. Two-choice oviposition assays determined that four-day-old gravid femaleP. interpunctella preferred to lay eggs on dishes containing cornmeal-based rearing diet compared to empty dishes. Pieces of cheesecloth contaminated by fifth instar larvae elicited more oviposition than untreated cheesecloth or dishes with food. The combination of larval contamination and food was preferred over food only or larval contamination only in both two- and four-choice experiments. The factor(s) in larval contamination responsible for eliciting oviposition in female moths was extracted in hexane, confirming that organic semiochemicals are responsible for the effect. The oviposition-eliciting activity of larval contamination was retained on cheesecloth for up to 30 days following treatment with larvae, suggesting the active component(s) is stable and of low relative volatility. In two-choice windtunnel bioassays female moths initiated flight only when rearing food was present in one of the treatments, and they displayed the highest landing responses to a combination of larval contamination and food. Earlier work onP. interpunctella and related pyralid species found that larval contamination due to secretions from the mandibular glands acted as both a spacing pheromone for wandering larvae and as a kairomone for host-seeking parasitoid wasps. The present study suggests that the same or a similar secretion acts as an oviposition-eliciting pheromone for conspecific females.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 72 (1994), S. 173-180 
    ISSN: 1570-7458
    Keywords: feeding performance ; diapausing propensity ; genetic correlation ; heritability ; host-range ; insect-plant interactions ; Lepidoptera ; Tortricidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Evolutionary constraints on the ability of herbivores to efficiently use a set of phytochemically similar hosts, while maintaining a high performance on phytochemically different hosts, are central in explaining the predominance of host specialization in phytophagous insects. Such feeding trade-offs could be manifested within insect populations as negative genetic correlations in fitness on different host species. We tested the hypothesis that feeding trade-offs were present within a population of the obliquebanded leafroller,Choristoneura rosaceana (Harris). Components of fitness were measured in families originating from an apple orchard that were fed on four host-plant species in the laboratory. Under the conditions of this experiment, all across-host genetic correlations were strongly positive, suggesting that this population comprised true generalists. With the exception of diapausing propensity, the heritability of the fitness components tended to be lower in caterpillars fed on apple leaves than in insects fed other hosts. This suggests a constraint on the selective response of the fitness components in the orchard environment.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 71 (1994), S. 177-180 
    ISSN: 1570-7458
    Keywords: aflatoxin ; Carophilus ; Zea mays ; corn ; plant resistance ; Coleoptera ; Nitidulidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 72 (1994), S. 17-23 
    ISSN: 1570-7458
    Keywords: plant varietal resistance ; armyworm ; Spodoptera exempta ; leaf extracts ; Zea mays ; feeding deterrent ; toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Maize (Zea mays L.) leaf tissue of cv Bastille and cv Michoacan 12 was extracted with n-hexane. The extracts were bioassayed against 5th instar African armyworm,Spodoptera exempta (Walker)(Lepidoptera: Noctuidae), by feeding the larvae on agar based media or sucrose impregnated glass fibre discs. The hexane extract of the ‘resistant’ cv Bastille exhibited feeding deterrency and toxicity which were not shown by the ‘susceptible’ cv Michoacan 12. The hexane extract of cv Bastille was adsorbed onto silica gel, the solution filtered off and the adsorbed component taken up into ethyl acetate. Bioassay of these fractions indicated that the toxic and deterrent action was retained in the ethyl acetate fraction. Preparative thin layer chromatography of the ethyl acetate fraction isolated two biologically active constituents. These were both growth inhibitors and lethal by ingestion to the 5th instar African armyworm. Implications for resistance in maize varieties to insect pests are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 72 (1994), S. 25-31 
    ISSN: 1570-7458
    Keywords: diapause induction ; photoperiod ; temperature ; Phyllonorycter blancardella ; spotted tentiform leafminer ; Lepidoptera ; Gracillariidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The role of photoperiod and temperature in the induction of overwintering diapause inPhyllonorycter blancardella (F.) (Lepidoptera: Gracillariidae) was examined in the laboratory and field using leafminers from commercial apple orchards in Ontario, Canada.P. blancardella exhibited a long-day response to photoperiod: long daylengths resulted in uninterrupted development whereas short daylengths induced diapause. The estimated critical photoperiod for diapause induction was L14.25∶D9.75. The larvae of leafminers destined to enter diapause took ca. 3× longer to complete development than the larvae of non-diapausing leafminers. The development prolonging effect of photoperiod decreased with decreasing daylength. Temperature modified the diapause inducing effect of photoperiod. At L14.25∶D9.75, diapause incidence was similar at 15 and 20°C but was lower at 25°C. Photoperiod also altered the normal relationship between development rate and temperature. At L14.25∶D9.75, the duration of larval development of diapausing leafminers was similar at 15, 20 and 25°C. Temperature alone is unlikely to have a role in the induction of diapause because leafminers exposed to natural late summer and fall temperature regimes and L16∶D8 did not enter diapause.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Pyralidae ; Ectomyelois ceratoniae ; carob moth ; host-finding ; Phoenix dactylifera ; dates ; gas chromatography-electrophysiology ; mass spectrometry ; wind tunnel ; attraction ; volatiles ; headspace
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four volatile compounds emitted from fungus-infected date fruit,Phoenix dactylifera L., were identified using coupled gas chromatographic-electroantennographic recordings, coupled gas chromatographic-mass spectrometric analysis, electroantennographic assays of synthetic standards, and wind tunnel bioassays. These compounds were ethyl hexanoate, ethanol, acetaldehyde, and 2-phenylethanol. Wind tunnel bioassays showed that ethyl hexanoate was capable of stimulating upwind flight and landing on the source by mated female carob moths,Ectomyelois ceratoniae (Zeller). Addition of both ethanol and acetaldehyde to ethyl hexanoate resulted in an increase in attraction to a level similar to that found for date fruits. No such effect was noted for additions of 2-phenylethanol at the dosages tested. In this study, it appears that ethyl hexanoate is a dominant olfactory stimulant and attractant for mated female carob moths, and represents a novel compound with regard to previously identified lepidopteran host odor attractants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 70 (1994), S. 295-298 
    ISSN: 1570-7458
    Keywords: forest tent caterpillar moth ; Malacosoma disstria ; fluctuating asymmetry ; survival ability ; pest management ; Lepidoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Fluctuating asymmetry of the first tarsal segment of the proleg of the forest tent caterpiller mothMalacosoma disstria Hbn. (Lepidoptera: Lasiocampidae) was significantly inversely related to survival ability in the lab. The monitoring of population levels of fluctuating asymmetry could have important implications in pest management of this and other species by providing an indication of the health of a population.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 71 (1994), S. 33-39 
    ISSN: 1570-7458
    Keywords: Helicoverpa zea ; Noctuidae ; Lepidoptera ; Eucelatoria bryani ; Tachinidae ; Diptera ; host-parasitoid relationship ; host regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The parasitoidEucelatoria bryani Sabrosky regulates the larval behavior of its hostHelicoverpa zea (Boddie). Parasitized third, fourth and fifth instars burrow into the soil 0.7–3.4 days earlier than unparasitized larvae that normally enter the soil to pupate at the end of the fifth and final larval instar. Parasitized third instars molt once then burrow as fourth instars, one instar earlier than normal. WhenE. bryani pupariated on the soil surface in the field, none survived to the adult stage. However,E. bryani adults emerged from 49.2% of hosts that had burrowed into the soil. By accelerating the timing ofH. zea burrowing behavior and causing host larvae to enter the soil before death,E. bryani ensures its pupariation in an environment with improved protection against natural enemies and lethal temperatures.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Papilionidae ; Zerynthia ; Aristolochia ; herbivory ; phenology ; nutritional indices
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The main host plants of the butterflyZerynthia rumina L. (Lepidoptera: Papilionidae) in southern Spain occur in different habitats and in general do not grow sympatrically. Therefore, each single local butterfly population uses the particular host available within its range.Aristolochia longa L. is a tuberous perennial herb available only in the spring, whileA. baetica L. is an evergreen perennial vine with indeterminate growth. However, because of the toughness of older leaves, newly hatched larvae feed only on new leaves ofA. baetica, and most of these leaves are produced well before the larvae hatch. In laboratory experiments, caterpillars feeding on either new or matureA. longa leaves grew faster and converted food into biomass more efficiently than those feeding on newA. baetica leaves. These differences are related to variation in nutritional quality among the host plants. Estimates of butterfly abundance were lower in sites whereZ. rumina usesA. baetica, compared with those where the host isA. longa. The potential differential effect of these two food plants on the densities of local butterfly populations relying on them is discussed here.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Tortricidae ; Choristoneura fumiferana ; juvenile hormone analog ; fenoxycarb ; postembryonic development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Journal of insect behavior 7 (1994), S. 605-632 
    ISSN: 1572-8889
    Keywords: Heliothis ; Lepidoptera ; Noctuidae ; pheromone ; visual feedback
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract MaleHeliothis virescens (F.) (Lepidoptera: Noctuidae) were made to fly into a uniformly white and translucent tube within a large wind tunnel while responding to sex pheromone. Different visual patterns placed within the tube greatly affected the ability of the male moths to maintain upwind progress or remain oriented to the wind while in contact with the plume. Over 89% of males attempting to fly through a blank tube, lacking visual patterns, became disoriented, the males gaining or losing altitude and repeatedly hitting the sides of the tube. Patterns of 20–40 dots placed on the sides of the tube at or slightly above plume level resulted in high levels of sustained upwind flight (47–74%) relative to patterns placed directly below (30–40%), directly above (35%), or slightly below the level of the flight path (26–44%). Optimal upwind progression in pheromone-responding males occurred when image motion could be resolved both transversely (T), orthogonally to the longitudinal axis of the body relative to the horizontal plane of the environment, and longitudinally (L), along the body axis. Even very sparse patterns (single rows of dots) could elicit high levels of sustained upwind flight (53–63%) when positioned within the tube such that the males' movements would create both L and T image motion. However, successful negotiation of the tube was also unexpectedly facilitated by patterns apparently providing no horizontal transverse component for flying males but providing longitudinal flow while centering the moth in the plume through a symmetrical left-right input (4–40%).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    ISSN: 1572-8889
    Keywords: parasitoid ; foraging behavior ; Hymenoptera ; Cotesia ; Lepidoptera ; Pieris ; host location ; solitary ; gregarious ; specialist ; generalist
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the present study we apply a comparative approach, in combination with experimentation, to study behavior of two parasitoid species that attack caterpillar hosts with different feeding strategies (gregarious or solitary). In a semifield setup, consisting of clean cabbage plants and plants infested with one of two host species, the foraging behavior of the specialistCotesia rubecula, on obligate parasitoid of solitarily feedingPieris rapae larvae, was compared to that of the generalistCotesia glomerata, a polyphagous parasitoid of several Pieridae species (mainly the gregariously feedingPieris brassicae).Cotesia glomerata displayed equal propensity to search for and parasitize larvae of both host species. AlthoughC. glomerata exhibited a relatively plastic foraging behavior in that it searched differently under different host distribution conditions, its behavior seems more adapted to search for gregariously feeding hosts. Females exhibited a clear “area-restricted” search pattern and were more successful in finding the gregariously feeding caterpillars.Cotesia rubecula showed a higher propensity to search forP. rapae than forP. brassicae, i.e., females left the foraging setup significantly earlier when their natural hostP. rapae was not present.C. rubecula showed a more fixed foraging behavior, which seems adapted to foraging for solitarily feeding host larvae. In a setup with onlyP. rapae larvae, the foraging strategies of the two parasitoid species were quite similar. In a choice situationC. glomerata did not show a preference for one of the host species, whileCotesia rubecula showed a clear preference for its natural host species. The latter was shown by several behavioral parameters such as the number of first landings, allocation of search time, and percentage parasitization.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Journal of insect behavior 7 (1994), S. 885-889 
    ISSN: 1572-8889
    Keywords: Lepidoptera ; Noctuidae ; Mamestra brassicae ; male scents ; hair-pencils ; courtship
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    ISSN: 1572-8889
    Keywords: Tanacetum vulgare ; Tansy ; Lobesia botrana ; European grapevine moth ; Asteracea ; Lepidoptera ; Tortricidae ; oviposition ; behavior ; nonhost plant ; semiochemicals ; plant odor ; olfaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Females ofLobesia botrana Den. et Schiff. (Lepidoptera Tortricidae) are attracted in natural conditions by volatiles released by a nonhost plant: tansy (Tanacetum vulgare L.; Asteracea). We have shown that both tansy flowers and their odor inhibit oviposition behavior and mating behavior and reduce adult longevity. The mean number of eggs laid per female isolated with tansy flowers was reduced by up to 50% every 2 days during the 6 days of exposure. This reduction was maintained after the tansy was removed. In the presence of tansy essential oil, the egg-laying reduction ranged from about 30 to 80% according to the odor concentration. The number of spermatophores found in females isolated with tansy flowers was also reduced twofold compared to the control treatment, indicating that the presence of tansy reduced mating activity. This mating activity is strongly reduced, by two-thirds, when adults face the highest dose of essential oil compared to controls. The number of eggs laid by the controls cannot be explained by the number of spermatophores. Therefore, the reduction in oviposition has been attributed to the presence of tansy flowers or to the tansy odor. Tansy flowers and tansy odor increased male mortality during the exposure (10% in the control, 50% in the tansy treatment, and up to 98% in the odor treatment). The highest rates of male mortality occurred during the 4- to 6-day period of exposure to flowers or odor. Repellence resulting in sustained locomotor activity is a possible cause of such a mortality. Female mortality was increased only in response to the highest dose of odor. This increase might be due to egg retention, and not directly to a plant effect. We discuss the effects of tansy flower odor on different patterns relative to the reproductive behavior ofL. botrana and, especially, on oviposition behavior in the ecological context of plant selection and polyphagy.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 50 (1994), S. 176-181 
    ISSN: 1420-9071
    Keywords: Cardiac glycoside loss ; Danaus plexippus ; aging ; breakdown of chemical defense ; three trophic level interactions ; automimicry ; Lepidoptera ; Asclepias
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Monarch butterflies (Danaus plexippus) are unpalatable to various vertebrate predators because their larvae sequester bitter and emetic cardiac glycosides (CGs) from milkweed plants (Asclepias spp.). Here we show that the concentration of the defensive CGs decrease as individual butterflies age, regardless of the CGs' initial amounts or specific chemical structures. Consequently, individual monarch butterflies can change from being unpalatable models to palatable mimics during their lifetime. Since monarchs breed continuously over the spring and summer in North America, freshly emerged adult butterflies may serve as noxious models for older individuals which become automimics as they age.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Mycorrhiza 5 (1994), S. 119-124 
    ISSN: 1432-1890
    Keywords: Key words Glomus mosseae ; Manganese uptake ; Root exudation ; Manganese reduction ; Mycorrhizal effect ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The influence of rhizosphere microorganisms and vesicular-arbuscular (VA) mycorrhiza on manganese (Mn) uptake in maize (Zea mays L. cv. Tau) plants was studied in pot experiments under controlled environmental conditions. The plants were grown for 7 weeks in sterilized calcareous soil in pots having separate compartments for growth of roots and of VA mycorrhizal fungal hyphae. The soil was left either uninoculated (control) or prior to planting was inoculated with rhizosphere microorganisms only (MO-VA) or with rhizosphere microorganisms together with a VA mycorrhizal fungus [Glomus mosseae (Nicol and Gerd.) Gerdemann and Trappe] (MO+VA). Mycorrhiza treatment did not affect shoot dry weight, but root dry weight was slightly inhibited in the MO+VA and MO-VA treatments compared with the uninoculated control. Concentrations of Mn in shoots decreased in the order MO-VA〉MO+VA〉control. In the rhizosphere soil, the total microbial population was higher in mycorrhizal (MO+VA) than nonmycorrhizal (MO-VA) treatments, but the proportion of Mn-reducing microbial populations was fivefold higher in the nonmycorrhizal treatment, suggesting substantial qualitative changes in rhizosphere microbial populations upon root infection with the mycorrhizal fungi. The most important microbial group taking part in the reduction of Mn was fluorescent Pseudomonas. Mycorrhizal treatment decreased not only the number of Mn reducers but also the release of Mn-solubilizing root exudates, which were collected by percolation from maize plants cultivated in plastic tubes filled with gravel quartz sand. Compared with mycorrhizal plants, the root exudates of nonmycorrhizal plants had two fold higher capacity for reduction of Mn. Therefore, changes in both rhizosphere microbial population and root exudation are probably responsible for the lower acquisition of Mn in mycorrhizal plants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 18 (1994), S. 228-230 
    ISSN: 1432-0789
    Keywords: Fine root ; Root litter ; Biofertiliser ; Leucaena leucocephala ; Trigonella foenum-graecum ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The efficacy ofLeucaena leucocephala root litter as a natural biological fertiliser was assessed usingZea mays as a test plant. Up to 8% of the fine roots of the plants constituted root litter. This fine root litter was better than that ofTrigonella foenum-graecum at increasing the growth and productivity ofZea mays. The root litter increased the growth of maize shoots more than the growth of roots. This appears to be a general phenomenon when plant nutrients are insufficient, as in the present study.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Chemoecology 5-6 (1994), S. 75-77 
    ISSN: 1423-0445
    Keywords: larval host plants ; distribution ; Lepidoptera ; Noctuidae ; Othreis fullonia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The adult fruit piercing moth,Othreis fullonia, a native of the indo-Malaysian region, causes severe damage to fruits grown throughout the tropical and subtropical belt from Africa through Asia and Australia to the Pacific Islands. Plants of the family Menispermaceae and the genusErythrina (Fabaceae) serve as larval hosts but the adult moths prefer Menispermaceae plants for oviposition. In Africa, Asia and Australia, the moth does not lay eggs onErythrina since members of the Menispermaceae are abundant. However in the insular Pacific region, where most islands have few or no species of Menispermaceae, the introduced fruit piercing moth utilizesErythrina as an alternate larval host, and either depletes, endangers or causes the possible extinction of Menispermaceae.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    ISSN: 1423-0445
    Keywords: oviposition ; stimulants ; deterrents ; glucosinolates ; Lepidoptera ; Pieridae ; Pieris rapae ; Pieris napi oleracea ; Alliaria petiolata
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Differential acceptance of garlic mustard,Alliaria petiolata byPieris rapae L. andP. napi oleracea is explained by their differential sensitivities to oviposition stimulants and deterrents in the plant. Fractions containing the stimulants and deterrents were isolated by solvent partitioning between water and n-butanol and by open-column chromatography followed by HPLC.P. napi oleracea showed no preference when offered a choice ofA. petiolata or cabbage, but was strongly stimulated to oviposit by post-butanol water extracts ofA. petiolata. The most abundant glucosinolate in this extract was identified as sinigrin, which could explain the high degree of stimulatory activity.P. rapae preferred cabbage plants overA. petiolata, and the relatively low stimulatory activity was also associated with the glucosinolate-containing aqueous extract. However, this species was strongly stimulated by a fraction that contained small amounts of glucotropaeolin along with unknown compounds. Deterrents to both species were found in the butanol extract fromA. petiolata, andP. napi oleracea was more sensitive thanP. rapae to these deterrents. Some HPLC fractions from the BuOH extract were strongly deterrent toP. napi oleracea, but were inactive toP. rapae. The ecological significance of these behavioral differences between the twoPieris species is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Chemoecology 5-6 (1994), S. 127-138 
    ISSN: 1423-0445
    Keywords: sequestration ; defence substances ; toxic substances ; pheromones ; host selection ; aristolochic acids ; pyrrolizidine alkaloids ; grayanotoxins ; cyanoglycosides ; Lepidoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A number of aposematic butterfly and moth species sequester toxic substances from their host plants. Some of these insects can detect the toxic compounds during food assessment. Some pipevine swallowtails use aristolochic acids among the host finding cues during oviposition and larval feeding and accumulate the toxins in the body tissues throughout all life stages. Likewise, a danaine butterfly,Idea leuconoe, which sequesters high concentrations of pyrrolizidine alkaloids in the body, lays eggs in response to the specific alkaloid components contained in the apocynad host. Insect species sharing the same poisonous host plants may differ in the degree of sequestration of toxins. Two closely ralated aposematic geometrid moth species,Arichanna gaschkevitchii andA. melanaria, sequester a series of highly toxic diterpenoids (grayanotoxins) in different degrees, while a cryptic geometrid species,Biston robstus, does not sequester the toxins, illustrating the diversity in adaptation mechanisms even within the same subfamily. By contrast, a number of lepidopteran species store the same compounds though feeding upon taxonomically diverse plant species. A bitter cyanoglycoside, sarmentosin, was characterised from several moth species in the Geometridae, Zygaenidae and Yponomeutidae, and from the apollo butterflies,Parnassius spp. (Papilionidae), although each species feeds on different groups of plants. Interspecific similarities and differences in life history and ecology are discussed in relation to variable characteristics of sequestration of plant compounds among these lepidopteran insects.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Chemoecology 5-6 (1994), S. 101-117 
    ISSN: 1423-0445
    Keywords: cardenolides ; cardiac glycosides ; chemical defence induction ; latex ; parasitism ; predation ; sequestration ; Insecta ; Diptera ; Tachinidae ; Lepidoptera ; Nymphalidae ; Danainae ; Danaus plexippus ; Asclepiadaceae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The contribution of Miriam Rothschild to the “monarch cardenolide story” is reviewed in the light of the 1914 challenge by the evolutionary biologist, E.B. Poulton for North American chemists to explain the chemical basis of unpalatability in monarch butterflies and their milkweed host plants. This challenge had lain unaccepted for nearly 50 years until Miriam Rothschild took up the gauntlet and showed with the help of many able colleagues that monarchs are aposematically coloured because they sequester toxic cardenolides from milkweed host plants for use as a defence against predators. By virtue of Dr Rothschild's inspiration and industry, and subsequently that of Lincoln Brower and his colleagues, this tritrophic interaction has become a familiar paradigm for the evolution of chemical defences and warning colouration. We now know that the cardenolide contents of different milkweeds vary quantitatively, qualitatively and spatially, both within and among species and we are starting to appreciate the implications of such variation. However, as Dr Rothschild has pointed out in her publications, cardenolides have sometimes blinded us to reality and it is curious how little evidence there is for a defensive function to cardenolides in plants — especially against adapted specialists such as the monarch. Thus the review will conclude with a discussion of the significance of temporal variation and induction of cardenolide production in plants, the “lethal plant defence paradox” and an emphasis on the dynamics of the cardenolide-mediated interaction between milkweeds and monarch larvae.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Chemoecology 5-6 (1994), S. 139-146 
    ISSN: 1423-0445
    Keywords: biochemistry of plants ; sequestration by insects ; transformation by insects ; pyrrolizidine alkaloids ; alkaloidN-oxides ; Asteraceae ; Senecio ; Lepidoptera ; Arctiidae ; Tyria ; Creatonotos
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Among alkaloids the pyrrolizidine alkaloids (PAs) play a unique role in the interactions between plants and adapted insects. InSenecio spp. (Asteraceae) PAs are synthesized in the roots as alkaloidN-oxides which are specifically translocated into shootsvia the phloem-path and channeled to the preferred sites of storage (e.g. inflorescences) where they are stored in the cell vacuoles. In differentSenecio spp. senecionineN-oxide is produced as the common product of biosynthesis, which subsequentlyvia a number of simple but specific reactions is transformed into typical speciesspecific PA-patterns. Insects from diverse taxa sequester PAs for their own defense. Lepidopterans (e.g. arctiids such asTyria jacobaeae andCreatonotos transiens) may hydrolyze plant acquired ester-PAs and convert the resulting necine base into insect-specific PAs by esterification with an acid of their own metabolism. Adapted arctiids and the grasshopperZonocerus take up PAs in the state of the tertiary amine.N-Oxides are reduced in the guts prior to uptake. In the bodies the tertiary PAs are rapidlyN-oxidized by a specific mixed-function oxigenase and are maintained in theN-oxide state. The importance of the reversible interconversion of the nontoxicN-oxide (pro-toxine) into the toxic tertiary alkaloid is discussed as the specific feature of PAs in plant-insect interactions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Electronic Resource
    Electronic Resource
    Springer
    Chemoecology 5-6 (1994), S. 167-171 
    ISSN: 1423-0445
    Keywords: inhibition ; indigestibility ; defence ; alkaloid ; glycosidases ; Lepidoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Glycosidase inhibitors are widespread in plants and can be sequestered by Lepidoptera, for which they can presumably serve as defences by making the insects indigestible to a range of potential predators. As a result of this study of eight British species of moth and butterfly it was found that glycosidase inhibitors in the insects could then be detected in the larval food plants which were not previously known to contain them; however, some were only detectable in the plants after concentration. In some cases the inhibition of specific glycosidases by Lepidoptera was detected even though the insects had not apparently acquired them from their food plants. Inhibition ofβ-N-acetylglucosaminidase was observed in most of the adult Lepidoptera analysed but further work is required to identify the inhibitors, though they are likely to be nitrogen-containing compounds. Weak anti-HIV activity was also observed in the glycosidase-inhibiting fractions ofAcherontia atropos and the plantUrtica dioica.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    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.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Electronic Resource
    Electronic Resource
    Springer
    Chemoecology 5-6 (1994), S. 26-36 
    ISSN: 1423-0445
    Keywords: chemoreception ; olfaction ; plant volatiles ; electroantennogram ; combined GC-EAG ; evolutionary adaptation ; Lepidoptera ; Papilionidae ; Papilio polyxenes ; Papilio machaon hippocrates ; Papilio troilus ; Apiaceae ; Daucus carota ; Pastinaca sativa ; Asteraceae ; Artemisia dracunculus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Antennae of femalePapilio butterflies perceive many volatile plant constituents with widely differing, constituent-specific sensitivities. We compared the responses of threePapilio species to volatiles from host and non-host plants to assess species-specificity and the degree of evolutionary conservatism in olfactory responses. Since previous studies had demonstrated that the polar constituents in odor fromDaucus carota stimulate oviposition behavior inPapilio polyxenes, we collected headspace volatiles fromD. carota, Pastinaca sativa (both Apiaceae) andArtemisia dracunculus (Asteraceae) and separated the polar fraction of these volatiles by gas chromatography. GC-coupled electroantennograms (GC-EAG) were recorded from the speciesPapilio polyxenes, P. machaon hippocrates andP. troilus. In addition, the responses of the three species to five compounds known as generally occurring constituents of plant odor were recorded. The relative sensitivities for these compounds were nearly identical in all threePapilio species. The response spectra to the separated plant volatiles also showed considerable similarities among the species. From the limited set of GC peaks evoking a response in one of the species, 64% (D. carota), 44% (P. sativa) and 29% (A. dracunculus) also evoked a response in both of the other species. The responses of the two closely related Apiaceae feeders (P. polyxenes, P. m. hippocrates) to volatiles fromD. carota were more similar to each other than was either to the response ofP. troilus, which feeds on Lauraceae. However, this was not true for the responses to volatiles fromP. sativa. The least congruence among the three species was found in the responses to volatiles fromA. dracunculus, a non-host for all of them. The differences and similarities found in the response profiles of the threePapilio species are discussed with respect to evolutionary adaptation to host odor versus evolutionary conservatism in adaptation of olfactory receptors.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    ISSN: 1432-2048
    Keywords: Anthocyanin ; Cold stress ; mRNA ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Changes in anthocyanin content and transcript abundance for genes whose products function in general phenylpropanoid metabolism and the anthocyanin pathway were monitored in maize (Zea mays L.) seedlings during short-term, low-temperature treatment. Anthocyanin and mRNA abundance in sheaths of maize seedlings increased with the severity and duration of cold. Anthocyanin accumulation was found in all tested lines that were genotypically capable of any anthocyanin production. Within 24 h of transferring 7-d maize (B37N) seedlings to 10° C, phenylalanine ammonia-lyase (Pal) (EC 4.3.1.5)-homologous and chalcone synthase (C2) (EC 2.3.1.74) transcript levels increased at least 8- and 50-fold, respectively, and 4-coumarate:CoA ligase (4Cl) (EC 6.2.1.12)-homologous and chalcone isomerase (Chi) (EC 5.5.1.6)-homologous transcripts increased at least 3-fold over levels in unstressed plants. Time-course studies showed thatPal (EC 4.3.1.5) andC2-transcript levels remained relatively constant for the first 12 h of cold stress, dramatically increased over the next 12 h, and declined to pretreatment levels within 2 d of returning coldstressed seedlings to ambient (25° C) temperature. Transcripts4Cl (EC 6.2.1.12) andChi (EC 5.5.1.6) increased in abundance within 6 h of cold stress, exhibited no further increase over the next 36 h, and declined to pretreatment levels upon returning seedlings to 25° C. Transcripts homologous to two regulatory (R, C1) and three structural (A1,A2, andBz2) anthocyanin genes increased at least 7- to 10-fold during cold treatment, exhibiting similar kinetics of accumulation as forPal (EC 4.3.1.5) andC2 transcripts. Transcripts encoded byBz1, the anthocyanin structural gene for UDP:glucose-flavonol glucosyltransferase (EC 2.4.1.91), were relatively abundant in control tissues and exhibited only a transient increase during the cold period. Our studies suggest that the genes of the anthocyanin biosynthetic pathway can be consideredcor (Cold-Regulation) genes, and because this pathway is well defined, it is an excellent subject for characterizing plant molecular responses to low temperatures.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 17 (1994), S. 1-8 
    ISSN: 1432-0789
    Keywords: Ammonium excretion ; Azospirillum brasilense ; Auxine ; 2,4-Dichlor-phenoxy-acetic acid ; Nitrogen fixation ; Paranodulation ; Maize ; Zea mays ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Maize seedlings develop nodule-like tumour knots (para-nodules) along primary roots when treated with the auxin 2,4-dichlor-phenoxy-acetic acid (2,4-D). Inoculated NH 4 + -excreting Azospirillum brasilense cells were shown to colonize these tumours, mostly intracellularly, promoting a high level of N2 fixation when microaerophilic conditions were imposed. The nitrogenase activity inside the para-nodules was less sensitive to free O2 than in non-para-nodulating roots. Both light and electron microscopy showed a dense bacterial population inside intact tumour cells, with the major part of the cell infection along a central tumour tissue. The bacteria colonized the cytoplasm with a close attachment to inner cell membranes. In an auxin-free growth medium, young 2,4-D-induced para-nodules grew further to become mature differentiated root organs in which introduced bacteria survived with a stable population. These results provide evidence that gramineous plants are potentially able to create a symbiosis with diazotrophic bacteria in which the NH 4 + -excreting symbiont will colonize para-nodule tissue intracellularly, thus becoming well protected.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 231-238 
    ISSN: 1573-1561
    Keywords: Trichoplusia ni ; Lepidoptera ; Noctuidae ; sex pheromone ; behavior ; evolution ; sexual selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Male cabbage looper moths,Trichoplusia ni, from two colonies in which all females express an abnormal sex pheromone production phenotype were evaluated in a laboratory wind tunnel for upwind flight responses to the normal and abnormal sex pheromones. The abnormal sex pheromone blend consisted of 20 times as much (Z)-9-tetradecenyl acetate and 30-fold less (Z)-5-dodecenyl acetate compared to the normal pheromone blend. Initially, these males exhibited poor behavioral responses to the abnormal sex pheromone and maximum responses to the normal pheromone blend, indicating that there was no linkage between signal production and response. After 49 generations of laboratory rearing, males from the mutant colonies maintained good responses to the normal pheromone and increased their behavioral response to the abnormal sex pheromone to the same levels as for the normal pheromone. Over the same period, normal males maintained their preference for the normal pheromone. These results indicated that evolution had occurred in mutant colonies in favor of greater male responsiveness to the abnormal sex pheromone, resulting in the broadening of the response spectrum to pheromone blend ratios. This evolution presumably resulted from a mating advantage to those males that did not discriminate against mutant-type females in the mutant colonies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    ISSN: 1573-1561
    Keywords: Pieris rapae ; Pieris napi oleracea ; Lepidoptera ; Pieridae ; Barbarea vulgaris ; oviposition ; stimulants ; glucosinolates ; glucobarbarin ; glucobrassicin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The closely related butterflies,Pieris rapae andP. napi oleracea, readily laid eggs onBarbarea vulgaris in greenhouse cages. When offered a choice between cabbage andB. vulgaris, P. rapae showed no preference, butP. napi oleracea preferredB. vulgaris. Bioassays of extracts ofB. vulgaris foliage revealed the presence of oviposition deterrent(s) in l-butanol extracts as well as stimulants in the postbutanol water extracts. However, the deterrent effect was apparently outweighed by the strong stimulatory effect in the whole plants. The postbutanol water extract was preferred over an equivalent cabbage extract by both species, but more significantly in the case ofP. napi oleracea. The stimulants were isolated by open column chromatography and HPLC, and the activity was associated with three glucosinolates.P. napi oleracea was more sensitive thanP. rapae to the natural concentration of compounds1 and3, whereas both species were strongly stimulated to oviposit by natural concentrations of compound2. Compounds1 and2 were identified as (2R)-glucobarbarin and (2S)-glucobarbarin, respectively, and3 was identified as glucobrassicin, on the basis of their UV, mass, and NMR spectra. When the pure compounds were tested at the same concentrations applied to bean plants, the (2R)-glucobarbarin at 0.2 mg/plant was preferred over a standard cabbage extract by both butterfly species. However, at a dose of 0.02 mg/plant,P. rapae preferred the cabbage extract whereasP. napi oleracea still preferred the (2R)-glucobarbarin. No such difference in response of the two species to the same two concentrations of (2S)-glucobarbarin was obtained. The results indicate a distinct difference in sensitivity of these butterflies to the epimers of glucobarbarin, and the differences in behavioral responses of the two butterfly species depend to a large extent on the concentration of stimulant present.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 1039-1051 
    ISSN: 1573-1561
    Keywords: Pieris rapae ; Pieris napi oleracea ; Lepidoptera ; Pieridae ; oviposition ; deterrents ; cardenolides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Oviposition responses ofPieris rapae andP. napi oleracea to 18 cardenolides were compared under the same conditions. Effects of different concentrations of selected cardenolides were also tested. Most of the compounds were deterrent to oviposition by both insects, but to significantly different degrees.P. rapae were strongly deterred by K-strophanthoside, K-strophanthin-β, cymarin, convallatoxin, oleandrin, erysimoside, erychroside, and gitoxigenin. The most deterrent compounds forP. napi oleracea were erychroside, cymarin, erysimoside, convallatoxin, and K-strophanthoside. Strophanthidin-based glycosides were more deterrent than digitoxigenin-based ones, and the number and type of sugar substitutions can have profound effects on activity. Both similarities and contrasts were found in responses ofP. rapae andP. napi oleracea to these cardenolides. Cymarin was equally deterrent to bothPieris species at all concentrations tested. However, when compared withP. rapae, P. napi oleracea was less sensitive to most of the cardenolides.P. napi oleracea was insensitive to K-strophanthin-β and oleandrin at 0.5 × 10−4 M, which were highly deterrent toP. rapae.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 1063-1073 
    ISSN: 1573-1561
    Keywords: Oxime ether ; NMR data ; pheromone mimics ; ESG studies ; structure-response relationships ; turnip moth ; Agrotis segetum Schiff. ; Lepidoptera ; Noctuidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Oxime ether analogs of sex pheromone components of the turnip moth (Agrotis segetum Schiff.) were synthesized by the acidolytic opening of cyclic enol ethers withO-alkyl hydroxylamine hydrochlorides. The compounds varying in chain lengths and in the position of the C=N double bond were studied by electrophysiological single sensillum recordings (electrosen-sillography: ESG). The ESG data indicate in general reduced receptor interaction of all analogs investigated in comparison with natural pheromone components of the turnip moth. The data also show that the grade of decrease of receptor interaction depends on specific structural changes within the molecule. The results demonstrate high complementary pheromone-receptor relationships, predominantly depending on the position of the unsaturated group in the chain, whereas analogs with other structural changes are still recognized as a pheromone-like compound by the receptor.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 1825-1841 
    ISSN: 1573-1561
    Keywords: Epiphyas postvittana ; Lepidoptera ; Tortricidae ; electroantennogram ; pheromone ; dispenser ; apple ; mating ; disruption ; atmospheric concentration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The absorption and release of the pheromone ofEpiphyas postvititana (Lepidoptera: Tortricidae),E 11–14: OAc andE,E 9, 11–14: OAc (95:5) by apple leaves was studied using electroantennograms (EAG) and sticky traps baited with pheromone-treated leaves. Leaves exposed to an airstream containing pheromone reached a constant level of pheromone release within 3 min. Release occurred over a period greater than 24 hr, following removal of leaves from the pheromone-saturated environment. Pheromone-treated leaves were effective as lures in sticky traps for at least three nights, although the average catch per night decrease logarithmically with time. In the field, pheromone was detected by EAG on leaves harvested from up to 25 cm away from a central point source of pheromone. The shape of a surface representing equal pheromone re-release from leaves around a central point source was defined by interpolation from a three-dimensional transect. Leaves harvested from 5 cm under the dispensers showed the highest pheromone release rate. Leaves downwind of the dispensers also had higher release of pheromone. In a treated orchard, significantly higher EAG measurements were recorded in the rows of trees that contained dispensers, compared to grass interrows or untreated trees. The implications of foliar pheromone adsorption and release on atmospheric concentrations and insect behavior require further investigation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Tortricidae ; Acleris variana ; sex pheromone ; (E)-11,13-tetradecadienal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract (E)-11,13-Tetradecadienal (E11,13–14:Ald) is the major sex pheromone component of the eastern blackheaded budworm (EBB),Acleris variana (Fern.). The compound was identified in female pheromone gland extracts by coupled gas chromatographic-electroantennographic detection (GC-EAD), coupled GC-mass spectrometry in selected ion monitoring mode, and retention index calculations of candidate pheromone components.E11,13–14:Ald alone as trap bait was very attractive to male EBB. Addition of the corresponding diene alcohol or acetate or both did not enhance attraction. (Z)-11,13-Tetradecadienal in binary combination with (E)-11,13–14:Ald neither enhanced nor reduced trap catches. Increasing the amounts of pheromone from 0.01 to 10 µg increased trap catches, but increase of pheromone quantity above 100 µg proportionately reduced attraction. Stabilization of slowly polymerizingE11,13–14:Ald and development of a sustained, adequate release rate is required for pheromone-based monitoring of EBB populations.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 24 (1994), S. 35-49 
    ISSN: 1573-5028
    Keywords: acetyl CoA carboxylase ; cDNA Cloning ; herbicide ; nucleotide sequence ; purification ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Acetyl CoA carboxylase (EC 6.4.1.2) in plants is a chloroplast-localized, biotin-containing enzyme that catalyses the carboxylation of acetyl CoA to malonyl CoA, the first committed step of the fatty acid biosynthesis pathway. Acetyl CoA carboxylase is the target site for the monocotyledon-specific aryloxy-phenoxypropionate and cyclohexanedione groups of herbicides. We have purifed a herbicide-sensitive acetyl CoA carboxylase from maize leaves to homogeneity (specific activity 7 μmol min-1 mg-1), separating it during the purification from a minor herbicide-resistant acetyl CoA carboxylase. The purified enzyme is a dimer of 230 kDa subunits. Antibodies raised to the purified acetyl CoA carboxylase detected three cross-reacting clones in a maize leaf cDNA expression library, each having an insert of 4–4.5 kb. Restriction analysis and sequencing showed that the cDNAs were derived from two different transcripts. Comparison of the deduced amino acid sequences with those of chicken and yeast acetyl CoA carboxylases confirmed that both types encoded acetyl CoA carboxylase, corresponding to the C-terminal half of the enzyme. The overall identity of the maize and chicken sequences was 37% (58% similarity) but for some shorter regions was much higher. Analysis of six other acetyl CoA carboxylase clones recovered from the maize cDNA library showed four belonged to one type and two to the other. The nucleotide sequence similarity between the two types of cDNA was approximately 95% in the coding region but considerably less in the 3′-untranslated region. Northern blot analysis of maize RNA showed a single band of 8.2–8.5 kb for acetyl CoA carboxylase mRNA. Southern blot hybridisations indicated that there are probably no more than two genes in maize for acetyl CoA carboxylase. The possible significance of two different cDNAs for acetyl CoA carboxylase is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    ISSN: 1573-5028
    Keywords: Opaque-2 and opaque-2 genes ; allelic diversity ; Opaque-2 proteins ; transcriptional activator ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The expression of the various members of the zein multigene family in maize endosperm is controlled by different regulatory loci. One of these loci, Opaque-2, coding for a bZIP transcriptional factor, controls the expression of a subset of zein genes. Analysis of genomic DNA from plants carrying wild-type (O2) or mutant o2 alleles shows specific DNA restriction patterns that correlate with transcript types and their various gene products. Northern and western analyses show the presence in different wild types of a 1.7 kb transcript coding for different sizes of normal O2 proteins that migrate as doublets in the 68–72 kDa range. Among the various o2 mutants analysed we showed the occurrence of various null-transcript alleles, the presence of alleles with a normal size transcript which, however, produce a different-sized o2 protein, and a mutant producing both a normal size transcript and a longer transcript, but generating only a single o2 product migrating around 40 kDa. Analysis of other mutations (o7, fl2) known to affect zien polypeptide synthesis shows no interference of these mutations in the expression of the O2 gene products. The overall results indicate the occurrence of micro heterogeneity in the O2 wild-type genes and a broad spectrum of o2 mutations, both producing different sizes of O2 or o2 proteins. A nomenclature of the O2 and o2 genes based on the RFLP, transcripts and products of the various alleles is presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 25 (1994), S. 909-916 
    ISSN: 1573-5028
    Keywords: heat shock 70 kDa protein ; multigene family ; polymerase chain reaction ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In this study we have analysed the multigene family coding for the cytoplasmic heat shock 70 kDa proteins (hsp70) inZea mays. Fully degenerate primers were used in a polymerase chain reaction (PCR) to amplify selected regions of the hsp70 genes. Sequence and Southern blot analysis reveals that at least three highly conserved genes exist in maize. In addition, amplification reveals the presence of a conserved intron in all genes examined. Expression analysis shows that the hsp70 genes studied represent members of the inducible and constitutive families. The results obtained may indicate that there are subfamilies of cytoplasmic hsp70 genes expressed in higher plants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 25 (1994), S. 343-353 
    ISSN: 1573-5028
    Keywords: cytochrome P450 ; flower development ; meristem-specific gene ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four cDNA clones exhibiting preferential hybridization to transcripts present in developing maize tassels were isolated by differential screening. One of these cDNA clones hybridizes to transcripts detectable only in the shoot apex. The abundance of this transcript is significantly higher in developing inflorescence apices than in vegetative apices. DNA sequence analysis of a 2107 nucleotide cDNA clone corresponding to this transcript revealed that the transcript encodes a polypeptide of 547 amino acids, with a molecular mass of 58.4 kDa. This polypeptide shares significant sequence similarity with members of the cytochrome P450 monooxygenase gene superfamily, including the conserved C-terminal domains typical of the cytochrome P450 monooxygenases.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 25 (1994), S. 565-568 
    ISSN: 1573-5028
    Keywords: chromatin ; high-mobility-group (HMG) proteins ; protein stability ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Chromosomal non-histone high-mobility-group (HMG) proteins represent essential components of eukaryotic chromatin and have also been isolated from a variety of plants. In maize, studies on structure and function of the two larger of the four major HMG proteins have recently been performed and are now extended by analysis of theirin vivo stability using pulse-chase experiments in a cell suspension culture. The half-life of the analyzed HMGa and HMGb proteins was found to be 65 h or more than 78 h, respectively.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 25 (1994), S. 817-828 
    ISSN: 1573-5028
    Keywords: B-Peru ; germinal revertants ; Mutator ; tandem duplication ; unequal recombination ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Theb locus ofZea mays encodes a transcriptional activator of the anthocyanin biosynthetic pathway. TheB-Peru allele is expressed in the aleurone layer of the seed, which results in dark purple pigmentation of this tissue. An unstableMutator-inducedB-Peru mutant allele,b-Perum220, displays weak, variable pigment and a high germinal reversion rate not characteristic of otherMutator insertions. Characterization of relevant regions ofb-Perum220 revealed aMu2 element insertion in one copy of a 534 bp sequence. This 534 bp sequence is tandemly triplicated in the progenitorB-Peru allele, upstream of theB-Peru transcription start site. In addition to theMu2 insertion, theb-Perum220 allele contains a newly formed large tandem duplication of 4.0 kb, which includes the promoter region and the first three exons of theB-Peru gene. TheMu2 element does not reside at any of the duplication breakpoints. The molecular study of eleven independent germinal revertants revealed five structural classes including structures in which the 4.0 kb tandem duplication is partially or completely deleted, theMu2 element is partially or completely deleted, or a combination of these events has occurred. We hypothesize that most of the revertants arose by unequal recombination between the duplicated regions. Based on these structural analyses, models are discussed to explain the reducedb gene expression inb-Perum220.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    ISSN: 1573-5028
    Keywords: primary response ; ferredoxin NADP+ oxidoreductase ; nitrate ; cycloheximide ; Zea mays ; roots
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To more fully understand the biochemical and molecular events which occur in plants exposed to nitrate, cDNAs whose accumulation was enhanced in nitrate- and cycloheximide-treated maize (Zea mays L. W64A × W182E) roots were isolated. The 340 bp Zmrprn 1 (for Zea mays root primary response to nitrate) cDNA also hybridized with a probe enriched for nitrate-induced sequences, and was characterized further. Sequence analysis of a near full-length cDNA (Zmrprn 1A) showed strong homology (〉90% amino acid identity) with a root ferredoxin-NADP+ oxidoreductase (FNR) of rice, and 45–50% amino acid identity with leaf FNR genes. When expressed in Escherichia coli, the Zmrprn 1A cDNA produced a protein with NADPH: ferricyanide reductase activity, consistent with the enzymatic properties of an FNR. The Zmrprn 1 cDNA hybridized with a 1.4 kb transcript which was expressed in the maize root primary response to nitrate. That is, mRNA levels in roots increased rapidly and transiently in response to external nitrate, and low levels of nitrate (10 μM) induced transcript accumulation. The accumulation of the Zmrprn 1 transcript was not prevented by cycloheximide, indicating that the cellular factor(s) required for expression were constitutively present in maize roots. The Zmrprn 1 mRNA accumulated specifically in response to nitrate, since neither K+ nor NH4 + treatment of roots caused transcript accumulation. Maize leaves had about 5% of the transcript level found in roots, indicating a strong preference for expression of Zmrprn 1 in roots. Analysis of maize genomic DNA indicated the presence of only a single gene or very small gene family for the Zmrprn 1. Together, the data indicate that Zmrprn 1A encodes a nitrate regulated maize root FNR.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    ISSN: 1573-5028
    Keywords: glutamine synthetase genes ; regulation ; nitrate ; ammonium ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The responses of the five cytosolic-type glutamine synthetase (GS1) genes of maize to treatment of hydroponically grown seedlings with 10 mM KNO3 or 10 mM NH4Cl were analyzed. Non-coding 3′ gene-specific hybridization probes and radioanalytic imaging were used to quantitate individual gene transcript levels in excised roots and shoots before treatment and at selected times after treatment. Genes GS1−1 and GS1−2 exhibited distinct organ-specific responses to treatment with either nitrogen source. The GS1−1 transcript level increased over three-fold in roots, but changed little if any in shoots. In contrast, the GS1−2 transcript level increased over two-fold in shoots, but decreased in roots after treatment. Increased transcript levels were evident at 4 h after treatment with either nitrogen source, with maximum accumulations present at 8 h after treatment with ammonium and at 10–12 h after treatment with nitrate. The GS1−3 gene transcript level showed little or no change after treatment with either nitrogen source. The GS1−4 gene transcript level remained constant in shoots of treated seedlings, whereas in roots, it exhibited relatively minor, but complex responses to these two nitrogen sources. The GS1−5 gene transcript is present in very small amounts in seedlings, making it difficult to analyze its response to metabolites in young plants. These results provide support for the possibility that different cytosolic GS genes of maize play distinct roles in nitrogen metabolism during plant growth and differentiation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Electronic Resource
    Electronic Resource
    Springer
    Plant molecular biology 25 (1994), S. 137-140 
    ISSN: 1573-5028
    Keywords: DNA acquisition ; retrotransposon ; retrovirus ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The recently identified maize retroelement Bs1 encodes domains of the plasma membrane H+-ATPase. This is the first example of host DNA captured by a plant retroelement and resembles the acquisition of oncogenes by vertebrate retroviruses. The ability to capture sequences from its host provides plant retroelements with a mechanism to alter gene structure which could be important for evolutionary adaptive change.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    ISSN: 1573-5028
    Keywords: intron ; maize ; splicing ; vectors ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The mechanisms of intron recognition and processing have been well-studied in mammals and yeast, but in plants the biochemistry of splicing is not known and the rules for intron recognition are not clearly defined. To increase understanding of intron processing in plants, we have constructed new pairs of vectors, pSuccess and pFail, to assess the efficiency of splicing in maize cultured cells. In the pFail series we use translation of pre-mRNA to monitor the amount of unspliced RNA. We inserted an ATG codon in the Bz2 (Bronze-2) intron in frame with luciferase: this construct will express luciferase activity only when splicing fails. In the pSuccess series the spliced message is monitored by inserting an ATG upstream of the Bz2 intron in frame with luciferase: this construct will express luciferase activity only when splicing succeeds. We show here, using both the wild-type Bz2 intron and the same intron with splice site mutations, that the efficiency of splicing can be estimated by the ratio between the luciferase activities of the vector pairs. We also show that mutations in the unique U-rich motif inside the intron can modulate splicing. In addition, a GC-rich insertion in the first exon increases the efficiency of splicing, suggesting that exons also play an important role in intron recognition and/or processing.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    ISSN: 1573-5028
    Keywords: Glutathione S-transferase ; herbicide safener ; inducible gene expression ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Several GSTs have been characterised in maize. GST I is a homodimer of 29 kDa subunits, GST II a hetrodimer of 27 kDa and 29 kDa subunits and GST IV a homodimer of 27 kDa subunits. We report the isolation and characterization of a herbicide-safener inducible cDNA clone, GST-27. Based on partial amino acid sequence, GST-27 encodes the 27 kDa subunit present in both glutathione S-transferase isoforms GST II and IV. Northern blotting was used to compare the expression patterns of GST-27 with that of GST-29. Transcripts corresponding to GST-27 were found to be constitutively expressed in RNA isolated from the root, but no expression was detected in RNA isolated from aerial parts of the plant. The application of herbicide safener caused a dramatic increase in the expression of GST-27 in all aerial plant parts tested. GST-29 was found to be constitutively expressed in RNA isolated from a number of maize tissues. The basal level of GST-29 expression showed a minimal increase upon herbicide safener treatment. Although a range of hormonal, environmental and physiological stimuli failed to elevate GST-27 levels, some increase in GST-27 mRNA was observed in the late stages of leaf senescence and after treatments resulting in phytotoxic effects.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Electronic Resource
    Electronic Resource
    Springer
    Mycorrhiza 5 (1994), S. 119-124 
    ISSN: 1432-1890
    Keywords: Glomus mosseae ; Manganese uptake ; Root exudation ; Manganese reduction ; Mycorrhizal effect ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The influence of rhizosphere microorganisms and vesicular-arbuscular (VA) mycorrhiza on manganese (Mn) uptake in maize (Zea mays L. cv. Tau) plants was studied in pot experiments under controlled environmental conditions. The plants were grown for 7 weeks in sterilized calcareous soil in pots having separate compartments for growth of roots and of VA mycorrhizal fungal hyphae. The soil was left either uninoculated (control) or prior to planting was inoculated with rhizosphere microorganisms only (MO-VA) or with rhizosphere microorganisms together with a VA mycorrhizal fungus [Glomus mosseae (Nicol and Gerd.) Gerdemann and Trappe] (MO+VA). Mycorrhiza treatment did not affect shoot dry weight, but root dry weight was slightly inhibited in the MO+VA and MO-VA treatments compared with the uninoculated control. Concentrations of Mn in shoots decreased in the order MO-VA 〉 MO+VA 〉 control. In the rhizosphere soil, the total microbial population was higher in mycorrhizal (MO+VA) than nonmycorrhizal (MO-VA) treatments, but the proportion of Mn-reducing microbial populations was fivefold higher in the nonmycorrhizal treatment, suggesting substantial qualitative changes in rhizosphere microbial populations upon root infection with the mycorrhizal fungi. The most important microbial group taking part in the reduction of Mn was fluorescent Pseudomonas. Mycorrhizal treatment decreased not only the number of Mn reducers but also the release of Mn-solubilizing root exudates, which were collected by percolation from maize plants cultivated in plastic tubes filled with gravel quartz sand. Compared with mycorrhizal plants, the root exudates of nonmycorrhizal plants had two fold higher capacity for reduction of Mn. Therefore, changes in both rhizosphere microbial population and root exudation are probably responsible for the lower acquisition of Mn in mycorrhizal plants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    ISSN: 1432-2242
    Keywords: Sorghum ; Zea mays ; Phylogeny rDNA sequence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The phylogenetic relationships of the genus Sorghum and related genera were studied by sequencing the nuclear ribosomal DNA (rDNA) internal transcribed spacer region (ITS). DNA was extracted from 15 Sorghum accessions, including one accession from each of the sections Chaetosorghum and Heterosorghum, four accessions from Parasorghum, two accessions from Stiposorghum, and seven representatives from three species of the section Sorghum (one accession from each of S. propinquum and S. halepense, and five races of S. bicolor). The maize (Zea mays) line, H95, and an accession from Cleistachne sorghoides were also included in the study. Variable nucleotides were used to construct a strict consensus phylogenetic tree. The analyses indicate that S. propinquum, S. halepense and S. bicolor subsp. arundinaceum race aethiopicum may be the closest wild relatives of cultivated sorghum; Sorghum nitidum may be the closest 2n=10 relative to S. bicolor, the sections Chaetosorghum and Heterosorghum appear closely related to each other and more closely related to the section Sorghum than Parasorghum; and the section Parasorghum is not monophyletic. The results also indicate that the genus Sorghum is a very ancient and diverse group.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 89 (1994), S. 259-264 
    ISSN: 1432-2242
    Keywords: RFLP ; Bootstrap ; Sampling variance ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Knowledge of genetic relationships among genotypes is useful in a plant breeding program because it permits the organization of germplasm and provides for more efficient sampling. The genetic distance (GD) among genotypes can be estimated using random restriction fragment length polymorphisms (RFLPs) as molecular markers. Knowledge of the sampling variance associated with RFLP markers is needed to determine how many markers are required for a given level of precision in the estimate of GD. The sampling variance for GD among all pairs of 37 maize (Z. mays L.) inbred lines was estimated from 1202 RFLPs. The 1202 polymorphisms were generated from 251 enzyme-probe combinations (EPC). The sampling variance was used to determine how large a sample of RFLPs was required to provide a given level of precision. The coefficient of variation (CV) associated with GD has a nearly linear relationship between its expected standard deviation and mean. The magnitude of the decrease in the mean CV for GD with increasing numbers of bands was dependent upon the sampling unit; e.g., individual polymorphic bands vs EPC, and the degree of relatedness among the inbreds compared. The rate of reduction in mean CV with increasing sample size was the same regardless of the restriction enzyme used, BamHI, EcoRI or HindIII, when the bootstrap sampling units were individual polymorphic bands. In constrast, although the rate of reduction (slopes) was the same, the intercepts of the mean CVs were different when EPCs were used as the bootstrap sampling unit. This difference was due to the higher number of bands per EPC in BamHI (4.94) compared with EcoRI (4.83) and HindIII (4.63).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 88 (1994), S. 780-784 
    ISSN: 1432-2242
    Keywords: Acetochlor tolerance ; Gene expression Pollen selection ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The objectives of this research were to determine if genes controlling the reaction to the herbicide acetochlor in maize (Zea mays L.) are active during both the haploid and the diploid phases of the life cycle and if pollen selection can be utilized for improving sporophytic resistance. Pollen of eight inbred lines, previously characterized through sporophytic analysis for the level of tolerance to acetochlor, showed a differential reaction to the herbicide forin vitro tube length; moreover, such pollen reactions proved to be significantly correlated (r =0.786*,df=6) with those of the sporophytes producing the pollen. Pollen analysis of two inbred lines (i.e. Mo17, tolerant, and B79, susceptible) and their single cross showed that thein vitro pollen-tube length reaction of the hybrid was intermediate between those of two parents. An experiment on pollen selection was then performed by growing tassels of Mo17xB79 in the presence of the herbicide. Pollen obtained from treated tassels showed a greater tolerance to acetochlor, assessed asin vitro tube length reaction, than pollen obtained from control tassels. Moreover, the backcross [B79 (Mo17xB79)] sporophytic population obtained using pollen from the treated tassels was more tolerant (as indicated by the fresh weight of plants grown in the presence of the herbicide) than was the control backcross population. The two populations did not differ when grown without the herbicide. These findings indicate that genes controlling the reaction to acetochlor in maize have haplodiploid expression; consequently, pollen selection can be applied for improving plant tolerance.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    ISSN: 1432-2242
    Keywords: Zea mays ; Aspartate kinase Threonine-overproducing mutants ; Lysine ; Methionine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The aspartate-derived amino-acid pathway leads to the production of the essential amino-acids lysine, methionine, threonine and isoleucine. Aspartate kinase (AK) is the first enzyme in this pathway and exists in isoforms that are feedback inhibited by lysine and threonine. Two maize (Zea mays L.) threonine-overproducing, lysine-insensitive AK mutants (Ask1-LT19 and Ask2-LT20) were previously isolated. The present study was conducted to determine the map location of Ask2 and to examine the amino-acid profiles of the Ask mutants. The threonine-overproducing trait conferred by Ask2-LT20 was mapped to the long arm of chromosome 2. Both mutants exhibited increased free threonine concentrations (nmol/mg dry weight) over wild-type. The percent free threonine increased from approximately 2% in wild-type kernels to 37–54% of the total free amino-acid pool in homozygous mutant kernels. Free methionine concentrations also increased significantly in homozygous mutants. Free lysine concentrations were increased but to a much lesser extent than threonine or methionine. In contrast to previous studies, free aspartate concentrations were observed to decrease, indicating a possible limiting factor in threonine synthesis. Total (free plus protein-bound) amino-acid analyses demonstrated a consistent, significant increase in threonine, methionine and lysine concentrations in the homozygous mutants. Significant increases in protein-bound (total minus free) threonine, methionine and lysine were observed in the Ask mutants, indicating adequate protein sinks to incorporate the increased free amino-acid concentrations. Total amino-acid contents (nmol/kernel) were approximately the same for mutant and wild-type kernels. In five inbred lines both Ask mutations conferred the threonine-overproducing phenotype, indicating high expressivity in different genetic backgrounds. These analyses are discussed in the context of the regulation of the aspartate-derived amino-acid pathway.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    ISSN: 1432-2242
    Keywords: Zea mays ; Opaque-2 ; RFLPs Marker-assisted selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Quality Protein Maize (QPM) is a name given to genetically modified opaque-2 maize with hard endosperm. The opaque-2 mutation conditions a reduction in the amount of zein seed storage protein; zeins are deficient in the essential amino acids lysine and tryptophan, and mutant seed have a higher nutritional value. To utilize the potential of opaque-2 maize, elite inbreds can be converted to o2/o2 forms and subsequently to hard endosperm opaque-2. Since opaque-2 is recessive and endosperm specific, conventional backcross procedures to convert elite inbreds to opaque-2 forms are inefficient. To alleviate this problem, a marker-assisted selection procedure was developed for the Texas A&M University Quality Protein Maize breeding program. Hybridization of an O2 cDNA probe to blots of DNA from plants carrying O2 and o2 alleles showed that restriction fragment length polymorphisms (RFLPs) exist between the W64A o2 allele and O2 alleles of Mo17 and TX5855 inbred lines. To identify the opaque2 genotypes in segregating populations, an RFLP marker assay combining the O2 cDNA probe and HindIII-digestion of genomic DNA was developed. The effectiveness of the O2 RFLP marker assay was tested under field conditions using F2 and backcross populations of several hard endosperm opaque-2 lines. A comparison of the genotypes identified by RFLP analysis with the seed phenotypes of the next generation indicated that this procedure is accurate and can be used for identifying O2/O2, O2/o2, and o2/o2 genotypes of individual juvenile plants in breeding populations.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    ISSN: 1573-9368
    Keywords: transient gene expression ; β-glucuronidase ; luciferase ; Hordeum vulgare ; Zea mays ; Nicotiana tabacum ; quantitation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The particle gun approach was used for the quantification of promoter efficiency in a test system for transient gene expression. β-Glucuronidase was used as reporter gene for determining promotote strength. The variability inherent in this gene transfer system was considerably reduced by calculating a transformation efficiency factor given by the expression of a cotransferred second reporter gene (firefly luciferase). The calibration of β-glucuronidase activity by the transformation efficiency factor caused a lower statistical variance of the values and allowed reliable results to be obtained with a smaller set of repetitions. The CaMV 35S promoter (as a control) and the monocot-specific promoters for maize polyubiquitin1, rice actin 1 and the maize-derivedEmu were characterized and compared with respect to expression strength, as tested under identical conditions in suspension cell cultures of maize, barley and tobacco. Compared to the 35S promoter, the monocot-specific promoters show up to 15-fold higher expression in maize and barley but give only weak expression in tobacco. No expression was found for the rice actin 1 promoter in tobacco. The level of reporter gene expression is influenced by the osmotic potential in the agar medium. For theEmu promoter, the calibrated β-glucuronidase activities remained mearly constant at low sucrose concentrations. Above 8% sucrose, the calibrated activities increased steadily with increasing osmotic conditions, reaching a three-to four-fold higher level at the highest sucrose concentration (32%) as compared to the standard concentration (4% sucrose) in the medium.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Electronic Resource
    Electronic Resource
    Springer
    Protoplasma 179 (1994), S. 131-141 
    ISSN: 1615-6102
    Keywords: Inosine diphosphatase ; Golgi membranes ; Zea mays ; Roots
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Light microsomes of corn roots, enriched in endoplasmic reticulum and Golgi membranes, have an IDPase activity which is stimulated by Triton X-100 and by cold storage. In the native state, the enzyme activity does not follow Michaelis-Menten kinetics. It hydrolyses IDP with K0.5 of about 900 μM and Vmax of 300–400 nmol Pi/mg protein/min. In the presence of Triton X-100, the enzyme is maximally stimulated and it renders to a Michaelis-Menten behavior with a Km of about 500 μM and a Vmax of 800–1200 nmol Pi/mg protein/min. The maximal effect of the detergent occurs at about 1 mM IDP (270%), being reduced (190%) at high IDP concentrations (〉2 mM) which, per se, have a slight stimulatory effect on the enzyme. On the other hand, we observed that ATP (〉2 mM) and adenosine inhibit the IDPase. The effects of the nucleotides and of the adenosine are abolished in the presence of Triton X-100, which makes the enzyme fully active. Furthermore, we observed that detergent treatment of the membranes reduces the change in the activation energy which occurs at 10 °C and eliminates cooperative effects, as revealed by the Arrhenius analysis and the Hill analysis, respectively. We also observed that IDPase inhibition by ATP is maximal at low IDP concentrations (1 mM), whereas it decreases at high concentrations of IDP (4 mM), which promote maximal velocities in the native enzyme. Conversely, the inhibitory effect of adenosine is not reduced at high IDP concentrations. Pyrophosphate also inhibits the IDPase, but the effect is non-competitive and it is cumulative with that of ATP. We also observed that the latent activity of the IDPase (Triton-stimulated IDPase) is reduced by pre-treatment of the membranes with glutaraldehyde. The results indicate that Golgi IDPase is an allosteric enzyme which is positively modulated by IDP and negatively modulated by ATP and adenosine. Pyrophosphate inhibits the IDPase, but it seems to act at the catalytic site, whereas the other modulators appear to interact with a distinct regulatory site.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    ISSN: 1615-6102
    Keywords: Auxin ; Mechanical stress ; Mechanosensor ; Microtubule orientation ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Plants respond to mechanical stress by adaptive changes in growth. Although this phenomenon is well established, the mechanism of the perception of mechanical forces by plant cells is not yet known. We provide evidence that the cortical microtubules sub-adjacent to the growth-controlling outer epidermal cell wall of maize coleoptiles respond to mechanical extension and compression by rapidly reorientating perpendicular to the direction of the effective force change. These findings shed new light on many seemingly unrelated observations on microtubule reorientation by growth factors such as light or phytohormones. Moreover, our results suggest that microtubules associated with the plasma membrane are causally involved in sensing vectorial forces and provide vectorial information to the cell that can be utilized in the orientation of plant organ expansion.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    ISSN: 1615-6102
    Keywords: Zea mays ; (1→3), (1→4)-β-D-glucan ; Glucan synthase ; Golgi apparatus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The synthesis of (1→3), (1→4)-β-D-glucan (MG) is associated with the Golgi apparatus of maize. Identification of in vitro reaction products by enzymic hydrolysis and separation of diagnostic oligosaccharides by HPLC was used as a specific assay for MG synthase activity. Large quantities of highly enriched membrane are needed to study the enzyme components of MG synthesis. We directly obtained highly enriched Golgi apparatus in a single flotation centrifugation, without the necessity of an initial downward centrifugation. This new procedure has improved the yield of Golgi apparatus, and has improved recovery of MG synthase activity. The substrate in glucan synthase reactions is UDP-Glc, but UDP-Glc is also a substrate in many other reactions, including the production of simple glucosides. In addition, much of the labeled Glc from UDP-Glc is broken down to Glc-1-P and Glc under MG synthase reaction conditions. We have explored some inhibitors of phosphatase, phosphorylase, phosphodiesterase, and glucosidase activities in order to minimize these competing reactions and increase the activity of MG synthase.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    ISSN: 1615-6102
    Keywords: Auxin ; Meristem (root) ; Quiescent center ; Root cap ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Using roots of maize, we tested the hypothesis that the origin and maintenance of the quiescent center (QC) are a consequence of polar auxin supply. Exposing roots to the polar auxin transport inhibitor 2,3,5-triiodobenzoic acid (TIBA), or to low temperature (4 °C, with subsequent return to 24 °C), enhances mitotic frequency within the QC. In both treatments, the QC most typically is activated at its distal face, and the protoderm/dermatogen undergoes several periclinal divisions. As a result, the root body penetrates and ruptures the root cap junction and the characteristic “closed” apical organization changes to “open”. A QC persists during these changes in apical organization, but it is diminished in size. The data from the TIBA-treated roots suggest a role for auxin in the origin and maintenance of the QC, and further, that alterations in QC dimensions are a consequence of polar auxin supply. We hypothesize that the root cap, and specifically the root cap initials, are important in regulating polar auxin movements towards the root apex, and hence are important in determining the status of the QC.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Electronic Resource
    Electronic Resource
    Springer
    Molecular genetics and genomics 242 (1994), S. 1-8 
    ISSN: 1617-4623
    Keywords: Zea mays ; Flavonoid biosynthesis ; P gene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We report here the first cloning of a chalcone flavonone isomerase gene (CHI) from maize. Northern blot experiments indicate that the maize CHI gene (ZmCHI1) is regulated in the pericarp by the P gene, a myb homologue. The ZmCHI1 gene encodes a 24.3 kDa product 55% and 58% identical to CHI-A and CHI-B from Petunia, respectively. This maize CHI gene has four exons and an intron-exon structure identical to the CHI-B gene of Petunia hybrida. RFLP mapping data indicate that some inbred lines contain two additional CHI-homologous sequences, suggesting an organization more complex than that found in Petunia or bean. The possibility that the additional CHI-homologous sequences are responsible for the lack of CHI mutants in maize will be discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 161 (1994), S. 225-232 
    ISSN: 1573-5036
    Keywords: minirhizotron ; root-length density ; soil core ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Detailed knowledge of the distribution of roots in the soil is important in understanding the extraction of water and nutrients from soil. Various techniques have been developed to monitor root-length density under field conditions. Excavation techniques, including soil cores, have long been considered to give reliable estimates of root-length density, but these techniques are laborious in sample collection and tedious in determination of root lengths. An attractive alternative for monitoring root-length density has been the minirhizotron whereby a periscope is inserted into a clear tube permanently installed in the soil for repeated and rapid measures of root development. The objective of this study was to compare the ability of the minirhizotron technique to measure root-length density as compared to the root-core technique. As in previous studies, substantial disagreement existed between the two techniques in the top 30-cm of the soil. The results from the minirhizotron consistently indicated a much lower root population than the root-core technique in the surface layer of soil. This is especially worrisome because more than 45% of the root-length density was found in this layer with the root-core technique. At deeper soil layers, the minirhizotron data proved to be no less variable than the root-core technique making the determination of statistically significant results difficult. Finally, the relationship between the minirhizotron and soil-core results varied with time even when the observations from the soil surface layer were ignored. Attempts to directly translate minirhizotron observations into a root-length density using a correlation approach would be suspect based on the results of this experiment.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 165 (1994), S. 315-321 
    ISSN: 1573-5036
    Keywords: cell wal's ; epidermis ; growth ; root development ; soil penetration ; stiffness ; Zea diploperennis ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The development of the epidermal layer of roots of Zea is traced from the quiescent centre to the zone where root hairs develop. In the zone of cell division a three layered coat forms on the outside of the epidermal cells consisting of the outer epidermal walls, overlaid by a two-layered pellicle composed of a thick fibrillar inner layer of polysaccharide, and a thin fibrillar outer layer of protein. The epidermal cells divide several times in the same longitudinal file but rarely across a radius to give a new longitudinal file. Thus, the radial walls become much thicker than all but the original transverse walls, and packets of up to 32 daughter cells derived from a single initial may be distinguished. The pellicle develops during these divisions as a continuum over the outer walls of the daughter cells. It is proposed that the pellicle provides a stiffening to the forward end of the root which permits it to penetrate soil without bending. Support for this hypothesis is shown by the Zea mays mutant Ageotropic in which the pellicle is absent, the epidermal surface is disorganized, and which grows crookedly through soil. In the zone of extension growth of normal roots of two Zea species the pellicle thins and disappears. Circumferential strips of the pellicle were peeled off the young epidermal cells and could be stretched to twice their length. This deformation is partly the result of the pellicle stretching and breaking above the attachments of the radial walls. After normal thinning of the pellicle, detachment of the radial walls at their outer ends produces a corrugated surface in the proximal zone of the root tips. In dicotyledons (e.g., soybean), there is no similar pellicle, but a stiff root tip is produced by a long multi-layered root cap, the proximal portion of which covers the elongating epidermal surface.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    ISSN: 1573-5044
    Keywords: bialaphos ; glufosinate ; phosphinothricin ; l-proline ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effectiveness of four phosphinothricin (PPT)-based selective agents were evaluated for use in maize transformation: glufosinate, bialaphos, Basta® and Herbiace®. Glufosinate and its commercial formulation, Basta®, were less effective in controlling growth of non-transgenic corn callus than the tripeptide, bialaphos, or its commercial formulation, Herbiace®. Addition of 25 mM l-proline had no significant effect on selection when using bialaphos. However, when l-proline was included with the selective agent glufosinate, selection was inhibited and callus growth was enhanced. At four weeks, callus growth on 0.3, 1.0 and 3.0 mg l-1 glufosinate in the presence of proline was 76, 43, and 21% of control growth, respectively, and in the absence of proline was only 32, 9, and 6% of control growth. Optimized selection protocols for Basta® and bialaphos yielded comparable numbers of transformants. Using these protocols, fertile transgenic plants were regenerated from transformed callus cultures.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    ISSN: 1573-5060
    Keywords: abscisic acid ; inheritance ; drought stress ; Zea mays ; maize
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary This study analyzes the components of phenotypic variation for abscisic acid (ABA) content in maize (Zea mays L.) leaves and the correlations with drought sensitivity index (DSI) and silk delay (SD), involved in the reaction to water deficit. Eight early- and seven medium-maturity inbreds were examined in field trials: in 1990 with low irrigation volume and in 1991 with low and high irrigation volumes. ABA concentration and DSI were investigated at growth stages (S) corresponding to stem elongation (S3), appearance of the first husks (S4), and mid-end of silking (S5). The ABA concentration was significantly higher in conditions of water deficit and in the later growth stage. The genetic component for ABA concentration attained higher relative values than those shown by DSI in the same growth stages and by SD; moreover, it increased from growth stage 3 to stage 5. The genotype × year and genotype × irrigation volume interactions were smaller for ABA concentration than for DSI and SD. The broad sense heritability on a plant basis, estimated in drought conditions, for ABA concentration ranged from 21.4 to 55.1% according to maturity group and growth stage. A wide variation was observed among lines for ABA concentration: the medium-maturity group showed a three-fold range (from 219 to 605 ng ABA g−1 dry weight). No clear relationships between ABA concentration, DSI and SD were found. These results indicate the feasibility of a selection for ABA concentration within segregating populations derived from crosses between the inbred lines herein tested.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 165 (1994), S. 293-300 
    ISSN: 1573-5036
    Keywords: gravitropism ; living systems theory ; nutation ; Phleum pratense L. ; simulation ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Roots have the ability to change the direction of their forward growth. Sometimes these directional changes are rapid, as in mutations, or they are slower, as in tropisms. The gravitational force is always present and roots have an efficient graviperception mechanism which enables them to initiate gravitropic movements. In trying to model and simulate the course of gravitropic root movements with a view to analyse the component processes, the following aspects of the plant's interaction with gravity have been considered: (1) The level of organization (organism, organ, cell) at which the movement process is expressed; (2) whether the gravity stimulation event is dynamic or static (i.e. whether or not physiologically significant displacements take place with respect to the gravity vector); (3) the sub-systems involved in movement and the processes which they regulate; (4) the mathematical characterization of the relevant sub-systems. A further allied topic is the nature of nutational movements and whether they are linked with gravitropic movements in some way. In considering how they can best be modelled, two types of nutational movements are proponed: stochastic nutation and circumnutation. Most, if not all, natural movements developed in response to static gravistimulation can be viewed as gravimorphisms. This applies at the levels of cell, organ and organism. However, when a system at any one of these levels experiences dynamic gravistimulation, because of its inherent homeostatic properties, it is induced to regenerate a state similar to that previously held. Thus, gravitropism is a regenerative gravimorphic process at the level of the organ.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 163 (1994), S. 267-277 
    ISSN: 1573-5036
    Keywords: cultivar ; critical root length density ; field experiment ; nitrate ; N utilization ; root growth ; uptake rate ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract In a 2-year field study conducted on a high fertilized Gleyic Luvisol in Stuttgart-Hohenheim significant differences among 10 maize cultivars were observed in soil nitrate depletion. The different capability of the cultivars to utilize nitrate particularly from the subsoil was positively correlated with (a) shoot N uptake at maturity, and (b) root length density (Lv) in the subsoil layers at silking. “Critical root length densities” for nitrate uptake were estimated by (a) calculating uptake rates per unit root length (U), (b) subsequent calculation of needed nitrate concentration in soil solution (C1) to sustain calculated U according to the Baldwin formula, and (c) reducing measured Lv and proportionate increase of U until needed concentration equaled measured concentration. Uptake rate generally increased with soil depth. “Critical root length densities” for cultivar Brummi (high measured root length densities and soil nitrate depletion) at 60–90 cm depth ranged from 7 % (generative growth) to 28 % (vegetative growth) of measured Lv Measured root length density of each other cultivar was higher than “critical root length density” for Brummi indicating that the root system of each cultivar examined would have been able to ensure N uptake of Brummi. Positive relationships between root length density and nitrate utilization as indicated by correlation analysis therefore could not be explained by model calculations. This might be due to simplifying assumptions made in the model, which are in contrast to non-ideal uptake conditions in the field, namely irregular distribution of roots and nitrate in the soil, limited root/soil contact, and differences between root zones in uptake activity. It is concluded from the field experiment that growing of cultivars selected for high N uptake-capacity of the shoots combined with “high” root length densities in the subsoil may improve the utilization of a high soil nitrate supply.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 167 (1994), S. 127-134 
    ISSN: 1573-5036
    Keywords: herbicides ; chlorsulfuron ; metsulfuron methyl ; root cap ultrastructure ; root growth ; Pisum sativum ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Herbicide residues may affect seedlings during early stages of their development. We studied this possibility by the use of light and electron microscopy after incubation of germinating seeds ofPisum sativum L. andZea mays L. with different concentrations of chlorsulfuron and metsulfuron-methyl. By in vitro experiments, we have shown that both herbicides caused growth reduction of the very young roots, and severe ultrastructural alterations and injuries of the root caps of both species. Chlorsulfuron caused increase of electron-dense material in the vacuoles, cytoplasmic degeneration even in the inner secretory cell layers of the cap, and disruption of the amyloplast envelopes with release of the statolithic starch grains. In the initial cell complex of the root cap, the herbicides caused the formation of large concentric aggregates of the rough ER and wall disformations in the cells adjacent to this complex. Scanning electron microscopic observations revealed a decrease of the slime layer ensheathing the root cap and the subapical root surface. We conclude that even in early stages of seed germination, both herbicides seriously affect the gravity perception centre (consisting of the statocytes), and the secretory tissue of the root caps, thus probably disturbing the processes of gravitropism and the protective slime secretion of the roots.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    ISSN: 1573-5087
    Keywords: auxin-transport ; indoleacetic acid ; maize ; photoinhibition ; transport ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The uptake of IAA into excised mesocotyls of non-irradiated maize seedlings was linear up to a concentration of about 4×M and in this range there was a tight coupling between the IAA in the stele and the cortex. Prior irradiation with white light of intact seedlings unbalanced this coupling. Lateral and longitudinal transport were affected differently. In the stele, the effect of prior irradiation on longitudinal transport was multiphasic, with an initial stimulatory effect followed by a negative effect at longer prior irradiation times. The lateral transport from the stele to the cortex showed no stimulatory effect and appeared to be inhibited within at least 15 min. The effect of the prior irradiation on longitudinal transport in the stele appeared to be a high intensity effect. In contrast, the effect of the prior irradiation on the lateral transport from the stele to the cortex was saturated at much lower intensities. The data suggest that the light induced change in the lateral transport of IAA between the two tissues may be due to changes either in the number of open lateral transport channels/carriers or in the conductivity of these channels/carriers.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Noctuidae ; Diachrysia chrysitis ; Diachrysia tutti ; pheromones ; sibling taxa ; electroantennographic responses ; biosynthesis ; cross-attraction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The noctuid sibling taxaDiachrysia chrysitis s. str. andD. tutti, of yet uncertain taxonomic status, have previously been shown to possess differences in morphology and to be attracted to different mixtures of the two presumed pheromone components (Z)-5-decenyl acetate and (Z)-7-decenyl acetate. TypicalD. tutti males (clearly broken forewing marking) are known to respond to a 2: 100 mixture of the two isomers, whereasD. chrysitis males (unbroken marking) are attracted to a 100: 10 mixture. We investigated female pheromone production and male electroantennographic (EAG) response inDiachrysia families raised in the laboratory from field-collected gravid females. Extracts of individual females from typicalD. tutti andD. chrysitis families were subjected to gas chromatography with simultaneous flame ionization and electroantennographic detection. All females produced mixtures of Z5- and Z7-10:OAc, but femaleD. chrysitis produced predominantly Z5-10:OAc and the antennae of their brothers responded more strongly to the Z5 peak than to the Z7-10:OAc peak, whereas the opposite was true forD. tutti families. The pheromone components were shown to be biosynthesized from hexadecanoic and tetradecanoic acid, respectively by Z11-desaturation followed by chain shortening, reduction, and acetylation. The EAG responses of males trapped with the typicalD. tutti andD. chrysitis blends, as well as with an intermediate blend, were investigated. Males trapped with theD. tutti mixture almost exclusively had a clearly broken wing marking and showed strongest EAG response to Z7-10:OAc. The intermediate blend and theD. chrysitis mixture gave more mixed catches, but with a prevalence of males with an unbroken (or almost unbroken) wing marking and with a higher mean response to Z5-10:OAc. Some males with typicalD. tutti EAG responses were attracted in the field to theD. chrysitis pheromone. In the flight tunnel someD. chrysitis males were attracted also to theD. tutti mixture. This indicates that cross attraction may take place between the two taxa under natural conditions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 171-181 
    ISSN: 1573-1561
    Keywords: Codling moth ; Cydia pomonella ; Lepidoptera ; Tortricidae ; communication disruption ; mating disruption ; sex pheromone ; (E,E)-8,10-dodecadien-1-ol ; (E,Z)-8,10-dodecadien-1-ol ; (Z,E)-8,10-dodecadien-1-ol ; dodecan-1-ol ; tetradecan-1-ol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In a small section of an apple orchard, six traps were placed each in control and test areas and baited with live virgin female codling moths. Gray elastomer septa were used to dispense communication disruptants around the traps. Dyed male codling moths were released in control and test areas, and the numbers of males captured in control and test traps were compared. In 1991, linear regression curves of percent communication disruption versus logarithm of dose were obtained for three compositions: (E,E)-8,10-dodecadien-1-ol, codlemone (1); codlemone + dodecan-1-ol + tetradecan-1-ol (2); and an equilibrium mixture of the four isomers of 8,10-dodecadien-1-ol (30, (61%EE, 14%ZE, 20%EZ, and 5%ZZ). All three regressions gaver 2 values greater than 0.90. At the 95% confidence limits, slopes and intercepts of compositions 1 and 2 were equivalent, and different from that of composition 3, which produced the greatest percentages of disruption at all doses. In 1992, five treatments were compared at a single dose: 1, 3, none (4), (Z,E)-8,10-dodecadien-1-ol (5), (E,Z)-8,10-dodecadien-1-ol (6). Compositions 5 and 6 gave the greatest and similar percentages of disruption and were different from codlemone (1) and 4 (95% confidence), but not from composition 3. Communication disruption produced by composition 3 was greater than (codlemone), which was greater than 4.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Tortricidae ; Cydia pomonella ; codling moth ; sex pheromone ; halogenated analogs ; isosteric replacements ; EAG ; single sensillum recording ; field trapping ; structure-activity relationship ; codlemone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Pest monitoring and control of the codling moth,Cydia pomonella L., have been developed using the main pheromone component of this species, (E,E)-8,10-dodecadienol (codlemone). However, the activity of codlemone is not satisfactory for pest control by mating disruption. Thus, we have synthesized halogenated analogs of codlemone to see if they could be used as new agents for pest control of the codling moth. Their biological activity was measured by electrophysiological techniques. In EAG screening, codlemone was the most active compound. F(10,11)-codlemone [(E,E)-10,11-difluoro-8,10-dodecadienol] and Cl-codlemone [(E,E)-11-chloro-8,10-undecadienol] elicited significant EAG responses, F(10,11)-codlemone triggering responses not significantly different from responses to codlemone. EAG cross-adaptation experiments and single sensillum recordings revealed that these compounds were detected by the same receptor neuron type as codlemone. No competitive inhibition with codlemone was observed from nonactive compounds. In field trapping, F(10,11)-codlemone and Cl-codlemone were more attractive to male codling moths than codlemone itself. Possible explanations of this activity are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    ISSN: 1573-1561
    Keywords: Citrus jambhiri ; Trichoplusia ni ; Lepidoptera ; Noctuidae ; bergapten ; furanocoumarins ; phototoxins ; plant-herbivore interactions ; psoralen ; ultraviolet-B radiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Projected decreases in stratospheric ozone may result in increases in shortwave ultraviolet (UVB) irradiation at the earth's surface. Furanocoumarins, phototoxic compounds found inCitrus jambhiri foliage, increase in concentration when these plants are grown under enhanced UVB. Survivorship schedules ofTrichoplusia ni (Lepidoptera: Noctuidae) caterpillars reared on plants in the presence and absence of enhanced UVB regimes differ significantly; larvae develop more slowly in early life when reared on plants exposed to increased UVB. This same developmental pattern is observed whenT. ni larvae are reared on artificial diets amended with ecologically appropriate amounts of furanocoumarins. Thus, anthropogenically derived changes in stratospheric ozone and concomitant changes in UV light quality at the earth's surface may influence ecological interactions between insects and their host plants by altering secondary metabolism and hence foliage quality for herbivores.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 639-650 
    ISSN: 1573-1561
    Keywords: Soybean ; lipoxygenase ; peroxidase ; polyphenol oxidase ; trypsin inhibitor ; ascorbate oxidase ; oxidative stress ; Lepidoptera ; Noctuidae ; Helicoverpa zea ; corn earworm ; Cerotoma trifurcata ; bean leaf beetle ; Coleoptera ; Chrysomelidae ; Spissistilus festinus ; three-cornered alfalfa hopper ; Homoptera ; Membracidae ; induced resistance ; interspecific competition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Variation in induced responses in soybean is shown to be dependent, in part, upon herbivore species. Herbivory by the phloem-feeding three-cornered alfalfa hopper caused increases in the activities of several oxidative enzymes including lipoxygenases, peroxidases, ascorbate oxidase, and polyphenol oxidase. Bean leaf beetle defoliation caused increased lipoxygenase activity, but had little effect upon peroxidase, polyphenol oxidase, ascorbate oxidase, or trypsin inhibitor levels in either field or greenhouse studies. In one field experiment, prior herbivory by the bean leaf beetle subsequently reduced the suitability of foliage to the corn earwormHelicoverpa zea. The contribution of these findings to emerging theories of insect-plant interactions is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    ISSN: 1573-1561
    Keywords: Sex pheromone ; (E)-11-hexadecenal ; (E)-11-hexadecen-1-yl acetate ; Palpita unionalis ; Lepidoptera ; Pyralidae ; Pyrustinae ; Anisodes sp. ; Geometridae ; jasmine moth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract (E)-11-Hexadecenal and (E)-11-hexadecen-1-yl acetate were found in abdomen tip extracts from females of the jasmine mothPalpita unionalis (Hübn). The identification was based on capillary GC analyses, mass spectrometry, and laboratory and field tests. In laboratory bioassays, both components elicited a low level of upwind flight by males. The two components when tested separately in the field were inactive, but the blend of the two components at a ratio of (3:7) was highly attractive to males. Traps baited with 1 mg of the two-component blend were competitive to traps baited with five virgin females. The addition of Z isomers components reduced male capture.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Tortricidae ; Spilonota ocellana ; eye-spotted bud moth ; sex pheromone ; (Z)-8-tetradecenyl acetate and (Z)-8-tetradecenyl alcohol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Response of male eye-spotted bud moth,Spilonota ocellana (Denis and Schiffermüller), to different ratios of synthetic sex pheromone components, (Z)-8-tetradecenyl acetate (Z8-14:OAc) and (Z)-8-tetradecenyl alcohol (Z8-14:OH), were compared in four North American locations and in one location in The Netherlands. In British Columbia, Nova Scotia, Michigan, and The Netherlands, a 99:1 blend ofZ8-14:OAc andZ8-14:OH captured significantly more maleS. ocellana thanZ8-14:OAc alone or binary blends containing 10–50%Z8-14:OH. In Ontario, where population sizes were low compared to the other four locations, trends in trap catches were similar, and there was no indication that maleS. ocellana responded differently to the tested pheromone blends. A 99:1 blend ofZ8-14:OAc andZ8-14:OH should be most effective in pheromone-based control programs ofS. ocellana in North America and in The Netherlands. Our results confirm earlier studies that a 99:1 blend ofZ8-14:OAc andZ8-14:OH captures significantly more maleS. ocellana thanZ8-14:OAc alone. However, our finding that a 99:1 blend ofZ8-14:OAc andZ8-14:OH is significantly more attractive than binary blends containing 10–50%Z8-14:OH differs from previous findings in Germany and Switzerland.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    ISSN: 1573-1561
    Keywords: Plutella xylostella ; Lepidoptera ; Plutellidae ; Brassica ; host plant attraction ; EAG ; bioassay ; host plant location ; plant volatiles ; mustard oils ; isothiocyanates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Olfactory attraction of female diamondback moths (Plutella xylostella) to odors of intact and homogenized host plants, as well as individual compounds characteristic of host plants, were investigated by behavioral and electrophysiological methods. Moths were attracted to odors ofBrassica juncea andB. napus seedlings in a Y-tube bioassay. Solvent fractions of homogenizedB. juncea leaves were attractive to moths whether or not isothiocyanates (IC) were present. Moths were attracted in Y-tube bioassays and to field traps baited with individual ICs. Volatiles fromB. juncea andB. napus elicited an electroantennogram (EAG) response and were attractive in the Y-tube bioassay. Allyl IC was shown to be the attractive component in homogenized plant volatiles but was found to be virtually absent from intact plant volatiles. Gas chromatographic fractionation of intact plant volatiles revealed a terpene-containing fraction to be most attractive to the moths. We were unable to isolate individual attractive compounds from this fraction. Our results suggest that certain elements of this fraction, possibly in combination, are important olfactory cues for host-plant finding by the diamondback moth with mustard oils playing an important and possibly synergistic role, particularly when plants are damaged.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    ISSN: 1573-1561
    Keywords: Cucurbitaceae ; Cucurbita pepo ; Insecta ; Lepidoptera ; Pyralidae ; Diaphania ; oviposition ; nitidalis ; pickleworm moth ; egg laying ; visitations ; stimulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Fourteen volatile compounds occurring in leaf trichomes of yellow squash (Cucurbita pepo L. cv. Early Prolific Straightneck) were identified. These compounds accounted for 83.5% of the volatile matrix. Ubiquitous constituents of the epidermis (myristic, palmitic, and stearic acids,n-tricosane, andn-pentacosane) accounted for 73.7%; these compounds were not bioassayed. The volatileso-,m-, andp-xylene, toluene, 2-heptanone, (R)-(+)- and (S)-(−)-limonene, and germacrene D were tested for their influence on attraction and oviposition by the pickleworm moth (Diaphania nitidalis Stoll.). No single compound, except germacrene D, was attractive. (R)-(+)-Limonene and 2-heptanone were weakly repellent. Mixtures of the highly volatile fractions were as attractive as volatiles emanating from whole, intact leaves. Oviposition levels on treated artificial sites corresponded with levels of visitation. Oviposition was significantly stimulated by “whole-leaf” volatiles, and (S)-(−)-limonene caused a slight but significant reduction.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 2127-2138 
    ISSN: 1573-1561
    Keywords: Attacus atlas ; biogenic amines ; chemical defense ; defensive glands of caterpillars ; histamine ; Lepidoptera ; Saturniidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The ability ofAttacus atlas caterpillars to spray a defensive secretion seems to be due to the fine structure of the integumental glands that produce it. The giant gland cells are fixed to stable cuticular rings surrounding the gland openings and tightly closed by cuticular lids. Probably by increasing hemolymph pressure, the lids are blasted off and the secretion spouts out. The fluid contains several aromatics, biogenic amines (e.g., acetylcholine, histamine), glycerol, and trehalose and exhibits tyrosinase activity. Deterrent effects of caterpillar secretion and hemolymph on predatory ants could be shown. Presumably the spraying process serves to apply the secretion to sensitive sites of vertebrate target organisms.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Pieridae ; Hymenoptera ; Braconidae ; cabbage ; Brussels sprouts ; behavior ; tritrophic interactions ; green-leaf volatiles ; herbivore-induced synomones ; elicitor ; caterpillar regurgitant ; Brassica oleracea ; Pieris brassicae ; Cotesia glomerata ; parasitoid ; wasp
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Induction of plant defense in response to herbivory includes the emission of synomones that attract the natural enemies of herbivores. We investigated whether mechanical damage to Brussels sprouts leaves (Brassica oleracea var.gemmifera) is sufficient to obtain attraction of the parasitoidCotesia glomerata or whether feeding byPieris brassicae caterpillars elicits the release of synomones not produced by mechanically damaged leaves. The response of the parasitoidCotesia glomerata to different types of simulated herbivory was observed. Flight-chamber dual-choice tests showed that mechanically damaged cabbage leaves were less attractive than herbivore-damaged leaves and mechanically damaged leaves treated with larval regurgitant. Chemical analysis of the headspace of undamaged, artificially damaged, caterpillar-infested, and caterpillar regurgitant-treated leaves showed that the plant responds to damage with an increased release of volatiles. Greenleaf volatiles and several terpenoids are the major components of cabbage leaf headspace. Terpenoids are emitted in analogous amounts in all treatments, including undamaged leaves. On the other hand, if the plant is infested by caterpillars or if caterpillar regurgitant is applied to damaged leaves, the emission of green-leaf volatiles is highly enhanced. Our data are in contrast with the induction of more specific synomones in other plant species, such as Lima bean and corn.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Electronic Resource
    Electronic Resource
    Springer
    World journal of microbiology and biotechnology 10 (1994), S. 406-409 
    ISSN: 1573-0972
    Keywords: Bacillus cereus-diarrhoeal-type enterotoxin ; Bacillus thuringiensis ; Coleoptera ; Diptera ; Lepidoptera ; thuringiensin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract At moderate concentration, 23 of 40 strains of Bacillus thuringiensis isolated from Sweden were toxic to Trichoplusia ni and five were toxic to Aedes aegypti. Five of the strains were toxic to Diabrotica undecimpunctata at high concentration, two were toxic to Heliothis virescens at low concentration and five produced thuringiensin (formerly called β-exotoxin). No strain was toxic towards the beet armyworm Spodoptera exigua at low concentration. Twenty-three of the strains produced a B. cereus-diarrhoeal-type enterotoxin.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    ISSN: 1573-1561
    Keywords: Bombyx mori ; Lepidoptera ; Bombiridae ; silkworm ; larvae ; ecdysone ; 20-hydroxyecdysone ; feeding behavior ; electrophysiology ; sensilla response ; chemoreceptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The feeding and gustatory responses to ecdysone and 20-hydroxyecdysone were investigated in the silkworm,Bombyx mori. 20-Hydroxyecdysone reduced feeding response strongly in fourth- and fifth-instar larvae, whereas ecdysone had no effect on feeding response. 20-Hydroxyecdysone stimulated the R receptor, the receptor to feeding deterrents, to a great degree. By contrast, ecdysone was much less effective for stimulating the R receptor. These results indicate that ecdysone and 20-hydroxyecdysone have different effects on feeding response due to different interactions with mouthpart chemoreceptors.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 183-198 
    ISSN: 1573-1561
    Keywords: Induced resistance ; protein quality ; Helicoverpa zea ; soybean ; Glycine max ; protease inhibitor ; lipoxygenase ; Lepidoptera ; noctuidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Resistance in soybean toHelicoverpa zea is comprised of both constitutive and inducible factors. In this study, we investigated the induction of resistance byH. zea in both greenhouse and field studies. In a greenhouse experiment, fourth-instarH. zea growth rates were reduced by 39% after 24 hr feeding and by 27% after 48 hr when larvae fed on previously wounded V3 foliage (cv. Forrest) compared with undamaged foliage. In a field study, the weight gain by larvae was more than 52% greater when larvae fed for 72 hr on undamaged R2/R3 soybean plants (cv. Braxton) compared to those that fed on previously wounded plants. A significant component of the induced resistance is due to a decline in the nutritional quality of foliar protein following foliar damage byH. zea. Foliar protein was extracted from damaged and undamaged foliage and incorporated into artificial diets. Larval growth was reduced 26% after four days and 49% after seven days on diets containing protein from damaged plants compared to larvae feeding on foliar protein from undamaged plants. Chemical analyses of protein quality also indicated a decline in quality in damaged plants compared to unwounded plants. Increases in lipoxygenase activity (53%), lipid peroxidation products (20%), and trypsin inhibitor content (34%) were observed in protein from wounded plants. Moreover, a 5.9% loss in free amines and 19% loss in total thiols occurred in protein from wounded plants. Larval feeding causes a significant increase in foliar lipoxygenase activity that varied among genotypes. Lipoxygenase isozymes were measured at pH 5.5, pH 7.0, and pH 8.5 in V3 stage plants of Forrest, Hark, D75-1069, and PI 417061 genotypes. Lipoxygenase activity in each genotype was significantly increased after 72 hr of larval feeding at each pH level tested, with the exception of lipoxygenase isozymes at pH 5.5 in genotype PI 417061. Larval feeding on R2/R3 stage plants (field-grown cv. Braxton) for six days also increased foliar lipoxygenase activity.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Geometridae ; Lambdina athasaria ; Lambdina fiscellaria fiscellaria ; Lambdina fiscellaria lugubrosa ; sex pheromone ; synergism ; 7,11-dimethylheptadecane ; 7-methylheptadecane ; 5,11-dimethylheptadecane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Two methylated hydrocarbons, 7-methylheptadecane (7) and 7,11-dimethylheptadecane (7,11), are female sex pheromone components of the spring hemlock looper (SHL),Lambdina athasaria (Walker). Compounds extracted from female pheromone glands were identified by coupled gas chromatographic-electroantennographic detection (GC-EAD) and coupled GC-mass spectrometry (GC-MS) in selected ion monitoring mode. In field trapping experiments, (7) and (7,11) by themselves were behaviorally inactive, but in combination attracted numerous male moths. (5,11)-Dimethylheptadecane (5,11) was detected in female SHL pheromone gland extracts, but did not enhance attraction to the binary blend of (7) and (7,11). The sex pheromone of SHL is related to that of congeneric eastern hemlock looper (EHL),Lambdina fiscellaria fiscellaria (Guen.) [(5,11) and 2,5-dimethylheptadecane (2,5)] and western hemlock looper (WHL),L.f. lugubrosa (Hulst) [(5,11), (2,5) and (7)]. Specificity of the pheromonal blend, spatial separation of coseasonal EHL and WHL, and temporal separation of sympatric EHL and SHL contribute to reproductive isolation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    ISSN: 1573-1561
    Keywords: Cranberry fruitworm ; Lepidoptera ; Pyralidae ; Acrobasis vaccinii ; sex pheromone ; (E,Z)-8,10-pentadecadien-l-ol acetate ; (E)-9-pentadecen-l-ol acetate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The following compounds and (approximate ratios) were identified in sex pheromone gland extracts of femaleAcrobasis vaccinii Riley by comparison of gas chromatography-mass spectrometric traces with those of synthetic standards: (E,Z)-, (Z,E)-, (Z,Z), and (E,E)-8, 10-pentadecadien-l-ol acetates (100:1:2:12), a dodecen-l-ol acetate (8), (Z)-8-, (Z)-9-, and (E)-9-pentadecen-l-ol acetates (3:23:4), two heptadecen-l-ol acetates (4:4), tetradecyl, pentadecyl, hexadecyl, and heptadecyl acetates (3:15:10:8), dodecan-l-ol (6), tetradecan-l-ol (5), and hexadecan-l-ol (23). The amount of (E,Z)-8, 10-pentadecadien-l-ol acetate (E8,Z10–15:Ac) in the extract was about 0.5 ng/female. Electroantennographic analysis of gas chromatographic fractions of female sex pheromone gland extract showed that the fraction containingE8,Z10–15:Ac elicited the greatest response. Alone,E8,Z10–15:Ac failed to elicit upwind flight of males in flight-tunnel tests, and traps baited with it did not catch males in field experiments. WhenE8,Z10–15:Ac was combined with (E)-9-pentadecen-l-ol acetate (100:4), male upwind flight response in flight-tunnel tests was equivalent to those obtained with extract of female sex pheromone glands (synthetic, 62%; natural, 51%), but the percent of males flying upwind that contacted the source was lower (synthetic, 47%; natural, 88%). The lower percent of source contact elicited by the synthetic pheromone could be a result of the difference in isomer ratios of 8,10–15:Ac in the natural and synthetic pheromone or could indicate that the synthetic pheromone is incomplete. Traps baited with the 100:4 combination caught large numbers of males in field experiments.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 3335-3344 
    ISSN: 1573-1561
    Keywords: Diabrotica virgifera virgifera ; fatty acids ; linoleic acid ; oleic acid ; stearic acid ; semiochemical ; attractants ; western corn rootworm ; host location ; Coleoptera ; Chrysomelidae ; Zea mays ; kairomone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A bioassay-driven sequential fractionation scheme was used to isolate fractions of a crude dichloromethane maize seedling extract behaviorally active to larvae of the western corn rootworm,Diabrotica virgifera virgifera LeConte. (Z,Z)-9,12-Octadecadienoic (linoleic) acid, (Z)-9-octadecenoic (oleic) acid, and octadecanoic (stearic) acid were identified from a purified fraction of maize extract that was attractive to western corn rootworm larvae in choice tests with equal levels of carbon dioxide on both sides of the choice. When synthetic linoleic, oleic, and stearic acids were tested together in the amounts and proportions found in the attractive fraction (1000, 800, and 300 ng of linoleic, oleic, and stearic acids, respectively), significantly more western corn rootworm larvae were found on the side with synthetic free fatty acids plus carbon dioxide than on the side with carbon dioxide alone. Results of the choice-test bioassays were not significantly different when the synthetic blend of free fatty acids was substituted for the purified maize fraction. Neither the purified extract nor the synthetic blend was behaviorally active in preliminary single-choice experiments without carbon dioxide. Linoleic, oleic, and stearic acids were also tested individually in the choice test bioassay with carbon dioxide on both sides of the choice to determine a dose-response curve. Linoleic and oleic acid each had one dose that was significantly attractive in conjunction with carbon dioxide on both sides of the choice, but stearic acid was not active in the doses tested.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 395-405 
    ISSN: 1573-1561
    Keywords: Douglas fir ; Pseudotsuga menziesii ; galactose ; terpenes ; sugars ; carbohydrates ; resistance ; western spruce budworm ; mortality ; Choristoneura occidentalis ; Lepidoptera ; Tortricidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The current year's growth of Douglas fir contains galactose, unusual in that this carbohydrate makes up 78.7% of the total carbohydrate fraction. An agar diet study was undertaken to determine the effects of galactose, other carbohydrates, and terpenes on western spruce budworm larval mortality, growth rate, and adult biomas production. All concentrations of the carbohydrates and terpenes tested, as well as other mineral elements not tested, were typical of the current year's foliage of Douglas fir. In experiment I, the diet containing 5.61% total carbohydrate did not significantly affect larval mortality when compared to the control diet. However, diets containing 9.45% and 15% total carbohydrate concentrations significantly increased larval mortality 64% and 96.1%, respectively, when compared to the control. Also in experiment I, terpenes alone (78.9% morality) and terpenes in combination with 9.45% and 15% total carbohydrates significantly increased larval mortality (97.2% and 100%, respectively) when compared to mortality on the control diet (44%). To determine which carbohydrate was causing the adverse effect, 6% glucose, 6% fructose, and 6% galactose were placed individually and in combination with terpenes in diets in experiment II. The 6% galactose diet significantly increased larval mortality and reduced growth rate when compared to the control, glucose, and fructose diets. Glucose resulted in 16% less larval mortality, significantly enhanced female larval growth rate and pupal weight, but did not affect male larval growth rate and pupal weight, when compared to the control. Fructose resulted in a significant decrease in larval mortality and a general trend of enhanced female and male larval growth rate and pupal weight. Larval mortality on terpenes alone was not significantly different from the control, but terpenes with 6% galactose increased larval mortality and decreased female and male growth rate and pupal weight significantly when compared to glucose-terpene and fructose-terpene diets. No significant interactions were found between carbohydrates and terpenes in either experiment.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 579-591 
    ISSN: 1573-1561
    Keywords: Aldehydes ; formulation ; 10,12-hexadecadienal ; 10,12,14-hexadecatrienal ; moth ; Manduca sexta ; Lepidoptera ; Sphingidae ; tobacco hornworm ; trapping
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In field experiments traps were baited with live females or with a two-, four-, or eight-component blend of the 16-carbon aldehydes previously identified as components of the sex pheromone emitted by femaleManduca sexta moths. The blends were formulated on rubber septa. Traps baited with a blend of all eight aldehydes captured moreM. sexta males than any other treatment. Septa loaded with 600 μg of the eight-component blend were attractive to males for about seven days in the field. Septa loaded with the eight-component blend and stored in a refrigerator at 4°C for a year released the conjugated diene and triene aldehydes at the same rate as freshly prepared septa and were equally attractive in the field.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    ISSN: 1573-1561
    Keywords: Sex pheromone ; attraction inhibitor ; behavioral antagonist ; mating disruption ; air permeation ; field EAG ; Cydia nigricana ; Tortricidae ; Lepidoptera ; pea moth ; (E,E)-8,10-dodecadien-1-yl acetate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Synthetic sex pheromone of the pea mothCydia nigricana, (E,E)-8,10-dodecadien-1-yl acetate (E8,E10–12: Ac), was applied in polyethylene dispensers at a rate of 30 g/ha and 600 dispensers/ha in a 0.6-ha pea field. The release rate ofE8,E10–12: Ac was 140 mg/ha/day after six days, and 82 mg/ha/day after 20 days. Aerial concentrations ofE8,E10–12: Ac, as measured by a portable EAG apparatus, ranged from 2 ± 2 to 7 ± 3 ng/m3. The antennal signal was high and rather constant within pea canopy, but was lower and fluctuated strongly above canopy. Initially, 〉99% isomerically pureE8,E10–12: Ac was released, and male moths were attracted to dispensers. After nine days, isomeric blend composition had equilibrated to approx. 92%E8,E10–12: Ac and 8% of the inhibitory isomersE,Z-,Z,E-, andZ8,Z10–12: Ac. Males were then repelled from the pheromone-permeated field. Traps baited with 100 µgE8,E10–12: Ac caught 258 ± 133C. nigricana males/trap in the control, but no males at all in the disruption field.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    ISSN: 1573-1561
    Keywords: Centaurea maculosa ; sesquiterpene lactone ; cnicin ; host-plant selection ; oviposition behavior ; antifeedant ; attractant ; Spodoptera littoralis ; Agapeta zoegana ; Stenodes straminea ; Pterolonche inspersa ; Lepidoptera ; Noctuidae ; Cochylidae ; Pterolonchidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The sesquiterpene lactone cnicin was extracted fromCentaurea maculosa andCentaurea vallesiaca. We examined its effects on the ovipositional response and larval development of generalist and specialist insect herbivores associated withC. maculosa. For the oviposition trials, three plant species (C. maculosa, Achillea millefolium, andCichorium intybus), half of which were sprayed with 3% of cnicin, were exposed to the specialist mothsStenodes straminea, Agapeta zoegana, andPterolonche inspersa in field cages. All three species significantly preferredC. maculosa to other plants andP. inspersa significantly preferred cnicin-sprayed plants to untreated plants for oviposition. Tested over all species, cnicin significantly increased the number of eggs laid on a given plant. A larval diet test examined the toxicity of cnicin for larvae of the generalist noctuid mothSpodoptera littoralis. Cnicin concentrations of 3% and 6% were lethal and 1% and 0.5% seriously inhibited growth and development. The larvae of theC. maculosa specialistStenodes straminea survived at 6% cnicin, but none of the pupae hatched.Agapeta zoegana was able to survive at 1% and 3% cnicin. Both specialists had difficulties with the artificial diet, but weight increase and survival was not further reduced when cnicin was present compared with on the control diet. In conclusion, cnicin influenced host recognition by the specialist species, and larvae of the generalist did not survive on natural levels of cnicin. Growth and survival of the specialist were not influenced by cnicin but were considerably hampered on artificial diet.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 1025-1037 
    ISSN: 1573-1561
    Keywords: Pieris rapae ; Pieris napi oleracea ; Lepidoptera ; Pieridae ; oviposition ; stimulants ; glucosinolates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The relative activities of 10 glucosinolates in stimulating oviposition byP. rapae andP. napi oleracea were compared under the same conditions. When tested at the same concentration, the structurally different glucosinolates stimulated both butterfly species to widely varying degrees. In most cases,P. rapae was more sensitive to aromatic and indole glucosinolates than to aliphatic representatives. This species responded even less to alkyl thio and sulfinyl glucosinolates. However,P. napi oleracea responded strongly to these aliphatic and sulfur-containing members of the group, and the relative activities of aromatic and aliphatic glucosinolates did not show a clear pattern for this species.P. napi oleracea was much more sensitive to low concentrations of sinigrin than wasP. rapae. The threshold concentration for response ofP. napi oleracea to sinigrin was 10−8 M, which was 100 times lower than forP. rapae, butP. rapae was more sensitive thanP. napi oleracea to changes in glucosinolate concentrations. For bothPieris species, an optimal concentration was reached, above which the response remained constant or tended to decrease.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    ISSN: 1573-1561
    Keywords: Cotesia rubecula ; Hymenoptera ; Braconidae ; Lepidoptera ; Pieridae ; Plutellidae ; Pieris rapae ; Brassica oleracea ; Plutella xylostella ; Phaselus vulgaris ; Geranium molle ; tritrophic interactions ; infochemicals ; volatiles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The role of airborne infochemicals in host selection by the parasitoidCotesia rubecula (Marshal) (Hymenoptera: Braconidae) was examined in a wind tunnel. To elucidate the role of volatile chemicals in attractingC. rubecula to cabbage infested by the host [Pieris rapae L. (Lepidoptera: Pieridae)], the potential sources of volatiles related toP. rapae infestation on cabbage were tested individually. The responses of females to nonhost plant species, bean and geranium, as well as to frass of a nonhost lepidopteran were also examined.C. rubecula was attracted to cabbage previously infested byP. rapae and to frass and regurgitate ofP. rapae. No attraction was observed to larvae ofP. rapae alone. Females were also attracted to mechanically damaged cabbage, cabbage previously infested byPlutella xylostella L. (Lepidoptera: Plutellidae) (a nonhost lepidopteran herbivore), and cabbage previously infested by snails (a nonhost, noninsect herbivore). Intact cabbage, bean, and geranium plants elicited no attraction. A low frequency of attraction was observed to mechanically damaged bean and geranium. Attraction was also observed to frass ofP. xylostella. Volatiles from cabbage related to damage, and volatiles from frass and regurgitate of the host seem to play an important role in guidingC. rubecula to plants infested by its host.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    ISSN: 1573-1561
    Keywords: Cotesia rubecula ; Hymenoptera ; Braconidae ; Lepidoptera ; Pieridae ; Plutellidae ; Pieris rapae ; Plutella xylostella ; Helix aspera ; Brassica oleracea ; Phaseolus vulgaris ; tritrophic interactions ; synomones ; infochemicals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The responses of the parasitoidCotesia rubecula to differently damaged cabbages were recorded during a series of choice tests. To determine if flyingC. rubecula can discriminate differences in the blend of volatiles emitted by cabbages damaged by different causes and how plant volatiles released from a distant source affect the searching behavior ofC. rubecula once searching on a plant, wasps were presented with a choice of plants located one behind the other and separated by a distance of 15 cm. The sources of damage were: cabbage damaged by the host (Pieris rapae), by a nonhost lepidopteran herbivore (Plutella xylostella), by a nonhost, noninsect herbivore (snail), and by mechanical means. The results showed that the site of first landing and the time spent searching on the leaves was influenced by the type of damage inflicted on plants. Wasps preferred to land on cabbages damaged by host and nonhost species of Lepidoptera over those damaged by snails and mechanical means. No preference was observed for first landing between cabbages damaged by the two species of Lepidoptera or between cabbages damaged by snails and mechanical means. Cabbage damaged byP. rapae was searched most intensively, followed by cabbage damaged byP. xylostella, cabbage damaged by snails, and cabbage damaged by mechanical means.C. rubecula differentiates between the volatile blends emitted by differently damaged cabbages, and it is attracted to volatiles related to recent lepidopteran damage. Wasps searched longer on freshly damaged than on leaves with older damage.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    ISSN: 1573-1561
    Keywords: Galleria mellonella ; Apis mellifera ; Pyralidae ; Apidae ; Lepidoptera ; Hymenoptera ; greater wax moth ; honeybee ; propolis ; plant resins ; phenolics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Bee propolis is a sticky amalgamation of plant resins collected by honeybees (Apis mellifera L.) and used in the hive for filling cracks and repairing combs. Propolis contains a diversity of compounds of plant origin, and is reported to have medicinal, antimicrobial, insecticidal, and phytotoxic properties. We examined the physical and chemical composition of North American samples of bee propolis from several sites in North America and tested for bioactivity against larvae of the greater wax moth (Galleria mellonella L.), a common apiary pest. The amount of methanol-extractable resin in samples from Ohio and Georgia ranged from 24% to 79% by weight. Propolis collected from hives in Ohio was more chemically diverse (over 30 compounds detected by paper chromatography) than material from south Georgia (fewer than 10 major compounds) and contained a lower proportion of methanol-insoluble beeswax. The paper chromatographic surveys revealed little variation in the chemical profile of specific hives over a six-month period and no differences between propolis from adjacent hives. Four flavonoids were identified from propolis collected in Ohio: kaempferol, galangin, 3,3′-dimethoxyquercetin and 3-methoxykaempferol. When mixed into artificial diet, fractionated propolis reduced larval growth of the greater wax moth, but not dramatically. An array of phenolics reported from propolis (caffeic acid, chrysin, ferulic acid, galangin, kaempferol, and quercetin) were bioassayed individually for effects on larvae, but none reduced larval growth at the concentrations tested, suggesting that wax moths are tolerant of some phenolics in their diet.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    ISSN: 1573-1561
    Keywords: Pieris rapae ; Lepidoptera ; Pieridae ; Plutellidae ; Plutella xylostella ; Cotesia rubecula ; Hymenoptera ; Braconidae ; Brassica oleracea capitata ; infochemicals ; plant volatiles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract To elucidate the identity of the volatile compounds that could be involved in the searching behavior of the parasitoidCotesia rubecula Marshall (Hymenoptera: Braconidae), the volatiles released by cabbage and frass of Lepidoptera feeding on cabbage were collected and analyzed using a gas chromatograph-mass spectrometer. The volatiles emitted by intact cabbage were α-pinene, β-pinene, myrcene, 1,8-cineole,n-hexyl acetate,cis-3-hexen-1-yl acetate, and dimethyl trisulfide. Mechanical damage on an intact plant induced the release of two more compounds,trans-2-hexenal and 1-methoxy-3-methylene-2-pentanone. Current feeding by larvae ofPieris rapae L. (Pieridae) induced the plant to release all the compounds released after mechanical damage and additionally 4-methyl-3-pentenal and allyl isothiocyanate. Current feeding by larvae ofPlutella xylostella L. (Plutellidae) induced the plant to release all the compounds present after mechanical damage and additionally allyl isothiocyanate. The volatiles emitted after feeding by the lepidopterans had ceased were the same as those emitted by cabbage damaged by mechanical means. The blend of volatiles emitted by frass was comprised of plant chemicals, mainly sulfur compounds. Frass ofP. rapae emitted allyl isothiocyanate, methyl isothiocyanate, methyl propyl sulfide, dimethyl trisulfide,S-methyl methane thiosulfinate, 4-methyl-3-pentenal,trans-2-hexenal, and 2,3-dihydro-4-methyl furan. Frass ofP. xylostella emitted only dimethyl trisulfide andS-methyl methane thiosulfinate. The blend of volatiles emitted by frass is herbivore-species specific.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 20 (1994), S. 1985-2001 
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Lasiocampidae ; Malacosoma disstria ; Orgyia leucostigma ; larva ; tannin ; tannic acid ; peritrophic membrane ; oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Final-instarMalacosoma disstria fed artificial diets containing tannic acid develop lethal pupal deformities. We examined some of the factors potentially underlying tannin sensitivity in this species, including the permeability of the peritrophic envelope to tannic acid and the chemical fate of tannic acid in the gut. Tannic acid does not penetrate the peritrophic envelope ofM. disstria, demonstrating that the containment of tannic acid within the endoperitrophic space is not sufficient to protect an insect herbivore from the adverse effects of ingested tannins. Ingested tannic acid undergoes extensive chemical modification in the midgut. Only 19–21 % of the high molecular weight components of the tannic acid ingested was recovered in the frass. Of two possible chemical fates of ingested tannic acid, oxidation is the predominant chemical transformation, whereas little hydrolysis occurs. Measurements of gut redox parameters showed that conditions in the midgut favor the oxidation of phenols. However, similar conditions occur in the midguts ofOrgyia leucostigma, in which no oxidation occurs. Therefore, oxidizing gut redox conditions do not necessarily lead to polyphenol oxidation in lepidopteran larvae. We conclude that the sensitivity ofM. disstria to ingested tannins is a consequence of their oxidation in the midgut.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    ISSN: 1573-1561
    Keywords: Apiaceae ; Peucedanum ; Lepidoptera ; Noctuidae ; Spodoptera littoralis ; HPLC ; preparative isolation ; furocoumarins ; furanocoumarins ; pyranocoumarins ; growth inhibition ; dietary utilization ; plant chemical diversity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Peucedanum arenarium Waldst. & Kit.,P. austriacum (Jacq.) Koch,P. coriaceum Reichenb.,P. longifolium Waldst. & Kit,P. officinale L.,P. oreoselinum (L.) Moench,P. ostruthium L., andP. palustre (L.) Moench accumulate different structural types of coumarins including simple coumarins, linear furanocoumarins, linear dihydropyranocoumarins, angular dihydrofuranocoumarins and angular dihydropyranocoumarins. Linear furanocoumarins, known for various biological activities, include some well-known antifeedants, such as bergapten, isopimpinellin, and xanthotoxin. The aim of this investigation was to screen the diverse coumarins fromPeucedanum for insecticidal activity. LC was used to analyze and isolate coumarins for the bioassays. A growth inhibition bioassay with 17 derivatives, comprising all structural types fromPeucedanum, carried out withSpodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) as test organism, indicated the majority of the linear furanocoumarins and the angular dihydrofuranocoumarin athamantin as active compounds. Oxygenation of the prenyl residue of linear furanocoumarins decreased activity. Further formation of an ester with angelic acid even resulted in complete inactivity. Five active linear furanocoumarins, bergapten, isopimpinellin, xanthotoxin, isoimperatorin, and imperatorin, and two linear furanocoumarins with a substituted furan ring, peucedanin and 8-methoxypeucedanin, were compared in a dietary utilization bioassay. Relative growth rate (RGR) and relative consumption rate (RCR) divided the tested coumarins in three groups of similar activity. Isopimpinellin and peucedanin slightly decreased RGR and RCR of the treated larvae, and xanthotoxin, isoimperatorin, and 8-methoxypeucedanin heavily decreased RGR and RCR. Bergapten and imperatorin differed by the lowest RGR values and rather high RCR values. The effects caused by these two coumarins indicate specific postingestive toxicity. The results obtained in this study add to the reputation of coumarins to be an effective chemical defense, postulating that chemical diversity is a necessary trait for well-defended plants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Pyralidae ; Chilo partellus ; spotted stem borer ; female sex pheromone ; (Z)-11-hexadecenal ; (Z)-11-hexadecen-1-ol ; multicomponent pheromones ; signal integrity ; dispensing technique ; trap efficiency ; proximity effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The effect of proximity of the release points of the two pheromone components (Z)-11-hexadecenal and (Z)-11-hexadecen-1-ol of the spotted stem borer,Chilo partellus (Lepidoptera: Pyralidae) on behavior of the males and on trapping efficiency was investigated. Separating the dispensers of the two components in the trap by a mere 3 cm resulted in a threefold decrease in trap performance, compared to very close release of the components. The result is attributed to possible distortion of the pheromone signal, resulting in confused behavior ofC. partellus males in the vicinity of the trap. The ethological and practical implications of the phenomenon are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 79 (1994), S. 149-161 
    ISSN: 1573-5060
    Keywords: maize ; germplasm ; cluster analysis ; landraces ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Two experiments were carried out with two objectives. First, to establish the phenetic relationships among the maize (Zea mays L.) landraces from Galicia (Northwestern Spain) maintained at the Misión Biológica de Galicia. Second, to assess the resemblance between a collection of Spanish populations (including the landraces from Galicia) and a set of US Corn Belt varieties. For the first objective 73 varieties from Galicia, along with 9 hybrid checks, were grown in 9×9 simple lattices at two locations for two years. For the second objective 131 populations from the US Corn Belt and Spain, along with 9 hybrid checks, were grown for three years in unreplicated experiments. Cluster analyses were carried out with the first principal components that accounted for a significant amount of the total variation. Four groups were found among the landraces from Galicia. The populations from Spain and America were classified as belonging to nine main groups. The replicated experiment was more accurate than the unreplicated one. However, it is concluded that an unreplicated test grown in several environments is accurate enough to detect the main groups, although some inaccuracies should be expected.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    ISSN: 1573-5060
    Keywords: maize ; Zea mays ; photoinhibition ; photosynthesis ; low-temperature adaptation ; breeding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Sixty-seven inbred lines of maize were evaluated for resistance to low-temperature photoinhibition of photosynthesis, using a pulse-modulated chlorophyll fluorescence technique. The evaluation procedure was based on leaf discs, which were exposed to a high irradiance (1000 µmol/m2/s) at 7°C. The efficiency of open PSII reaction centres as a reflection of overall photosynthesis was measured before and after a photoinhibition-inducing treatment. Exposure of leaf discs to photoinhibitory condition for 2, 4, and 8 hours resulted in an efficiency reduction of 30, 53 and 83%, respectively. Testing of inbred lines showed large differences for photoinhibition susceptibility. The difference in photosynthetic efficiency between the most extreme lines after a treatment of eight hours was 39%. Resistance to photoinhibition was shown to be relevant under cool field conditions. It proved to be a trait strongly amenable to selection.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Electronic Resource
    Electronic Resource
    Springer
    Photosynthesis research 39 (1994), S. 67-73 
    ISSN: 1573-5079
    Keywords: Zea mays ; C4-photosynthesis ; decarboxylation ; NADP-ME type ; l-malate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effect of structural analogues of l-malate was studied on NADP-malic enzyme purified from Zea mays L. leaves. Among the compounds tested, the organic acids behaved as more potent inhibitors at pH 7.0 than at pH 8.0, suggesting that the dimeric form was more susceptible to the inhibition than the tetrameric form of the enzyme. Oxalate, ketomalonate, hydroxymalonate, malonate, oxaloacetate, tartrate, α-hydroxybutyrate, α-ketobutyrate, α-ketoglutarate and α-hydroxyglutarate exhibited linear competitive inhibition with respect to the substrate l-malate at pH 8.0. On the other hand, glyoxylate and glycolate turned out to be non-competitive inhibitors, while glycolaldehyde, succinate, fumarate, maleate and β- and γ-hydroxybutyrate had no effect on the enzyme activity, at the concentrations assayed. These results suggest that the extent of inhibition was dependent on the size of the analogues and that the presence of an 1-carboxyl group along with a 2-hydroxyl or 2-keto group was important for binding of the substrate analogue to the enzyme.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    ISSN: 1573-5036
    Keywords: allelopathy ; crop rotation ; nitrogen utilization ; root growth ; soil nitrate depletion ; Vigna unguiculata ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract In the northern Guinea Savanna of Ghana (1984–1987) a field experiment was conducted to study the reasons for beneficial effects of rotating maize (Zea mays) and cowpea (Vigna unguiculata) on yield and N and P use of maize. The treatments included two cropping systems, maize monocropping and maize/cowpea rotation, two levels of nitrogen (0 and 80 kg N ha-1 as urea) and two levels of phosphorus application (0 and 60 kg ha-1 P as Volta phosphate rock). Yields and nutrient accumulation of maize were larger in rotation than in monocropping, independent of the N and P level. Fertilizer application (N and P) increased yields of maize in both cropping systems to the same extent. Nitrate contents of the soil after cowpea and after maize monoculture were comparable at the beginning of the cropping period. Also, potential nitrogen mineralization was only slightly larger after cowpea in the unfertilized plots. However, soil nitrate of fertilized plots was similar or even higher under monocropping than under crop rotation, especially in deeper soil layers and at the end of the cropping period. This indicates that in addition to the availability of mineral N, its use by the plants was limiting for the productivity of maize. Root length densities of maize were significant lower in monocropped maize than in maize grown in rotation. Soil physical parameters (infiltration, bulk density, aggregate stability and water capacity) showed a significant deterioration compared to a bush fallow plot, but differed only slightly between the cropping systems. Also in a pot experiment maize growth was much better in the soil from the crop rotation than from the monocropping plots, provided P was eliminated as the main growth-limiting factor. Since this effect persisted in spite of N application and optimization of soil physical properties by mixing the soil with polystyrol it is concluded that the results indicate that yield decline in maize monocropping might be due to allelopathic effects.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    ISSN: 1573-5036
    Keywords: C distribution ; native soil organic matter ; rhizosphere ; root released carbon ; wheat ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Wheat and maize were grown in a growth chamber with the atmospheric CO2 continuously labelled with 14C to study the translocation of assimilated carbon to the rhizosphere. Two different N levels in soil were applied. In maize 26–34% of the net assimilated 14C was translocated below ground, while in wheat higher values (40–58%) were found. However, due to the much higher shoot production in maize the total amount of carbon translocated below ground was similar to that of wheat. At high N relatively more of the C that was translocated to the root, was released into the soil due to increased root respiration and/or root exudation and subsequent microbial utilization and respiration. The evolution rate of unlabelled CO2 from the native soil organic matter decreased after about 25 days when wheat was grown at high N as compared to low N. This negative effect of high N in soil was not observed with maize.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 79 (1994), S. 13-18 
    ISSN: 1573-5060
    Keywords: Zea mays ; haploid induction ; maternal haploids ; inducer line ZMS ; maize
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Presented are the results of a two-year study of haploid maize plants in the field. The haploids were produced with the aid of inducer line ZMS. In total, 604 and 1030 haploids were obtained and studied in the first and second years, respectively. Tassels of haploid plants were found to be almost completley sterile. Fertility of ears was studied by pollinating them with the pollen from diploid inbred lines, the cross resulting in almost all of the haploid ears carrying kernels. On average 27.4 kernels per ear of haploid plant were obtained in the first year of study and 26.3 in the second. These gave rise to normal diploid plants. This property allows genotypes selected at the level of haploid plants to be involved in breeding process. Unusual plants were found among haploids, phenotypically resembling homozygous lines. It was assumed that the plants had resulted from spontaneous chromosome doubling in haploids. The results of comparative studies of progenies of unusual plants and inbred lines derived from the same synthetic population are presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Electronic Resource
    Electronic Resource
    Springer
    Plant growth regulation 14 (1994), S. 235-242 
    ISSN: 1573-5087
    Keywords: auxin transport ; calcium ; gravitropism ; root cap ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract There is evidence that the cap is the initial site of lateral auxin redistribution during the gravitropic response of roots. We tested this further by comparing asymmetric auxin redistribution across the tips of gravistimulated intact roots, decapped roots, isolated root caps and isolated apical sections taken from decapped roots. Gravistimulation caused asymmetric (downward) auxin movement across the tips of intact roots and isolated root caps but not across the tips of decapped roots or across isolated apical root segments. Naphthylphthalamic acid and pyrenoylbenzoic acid, inhibitors of polar auxin transport, inhibited asymmetric auxin redistribution across gravistimulated isolated root caps and across the tips of gravistimulated intact roots. For intact roots there was a positive correlation between the extent of inhibition of assymmetric auxin redistribution by polar auxin transport inhibitors and the extent of inhibition of asymmetric calcium chelating agent, ethylene glycol-bis(β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid, also caused parallel inhibition of asymmetric auxin redistribution and gravitropic curvature and this effect was reversed by subsequent treatment with calcium. The results support the hypothesis that the cap is a site of early development of auxin asymmetry in gravistimulated roots and that calcium plays an important role in the development of lateral auxin redistribution.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...