bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic basis of photoperiodic control of summer and winter diapause in geographic ecotypes of the rice stem maggot, Chlorops oryzae
Authors: Takeda Mitsuyoshi 
Published: October 2003

Abstract Chlorops oryzae Matsumura (Diptera: Chloropidae) is bivoltine in northern Japan but trivoltine in the southern part of the country. Larvae of the bivoltine strain (Akita, 39° N) develop without delay under L14:D10 but enter summer diapause in the mature larval stage under L15:D9. In contrast, larvae of the trivoltine strain (Aichi, 35° N) develop quickly under L15:D9 but enter summer diapause under L14:D10. The genetic basis of their different summer‐diapause behavior was analyzed by reciprocal crossing between the two ecotypes and backcrossing to the hybrids. Although a polygenic system seems to be involved, there is a single gene on the X‐chromosome exerting a major effect on summer diapause. The northern bivoltine ecotype has a longer critical photoperiod for the induction of winter diapause in the first larval stage and remains in diapause longer than the southern trivoltine ecotype. The differences in the critical photoperiod and the winter diapause duration between the two ecotypes seem to be controlled by a polygenic system but again a sex‐linked or closely linked gene (or genes) plays a major role. The two geographic ecotypes differ significantly in summer‐ and winter‐diapause traits, both of which are characterized by sex‐linked inheritance. Despite this, no apparent sterility or inviability in hybrids between the ecotypes occurs.
Phloem specific aphid resistance in Cucumis melo line AR 5: effects on feeding behaviour and performance of Aphis gossypii
Authors: Klingler John , Powell Glen , Thompson Gary A. , Isaacs Rufus 
Published: October 2003

AbstractThe feeding behaviour, excretion rate, and life history traits of the cotton‐melon aphid, Aphis gossypii (Glover) (Homoptera, Aphididae), were measured on a resistant melon, Cucumis melo L., breeding line, AR 5. The site of resistance detection by the aphids was determined using the electrical penetration graph (EPG) technique. EPG recordings showed that resistance is expressed within the host plant, rather than on its surface, because the time to first stylet penetration was not significantly different between AR 5 and the closely related susceptible breeding line, PMR 5. EPG patterns associated with stylet pathway activities of the aphids were not significantly different between the resistant and susceptible lines. Significant behavioural differences were observed only after stylets contacted phloem sieve elements. On AR 5, the duration of salivation after sieve element puncture (waveform E1) was significantly longer, and the number of aphids showing phloem sap ingestion (waveform E2) was significantly reduced. We conclude that the resistance mechanism producing the effects seen in this study acts within the phloem sieve elements. Monitoring of excretion rates on the two genotypes showed that aphid feeding was delayed and greatly reduced on the resistant genotype. Comparisons of aphid life history traits and population development between host plant genotypes showed that the effects of resistance act throughout aphid development and are highly effective at slowing down population increase.
Chemoreception of amino acids by female fourth‐ and sixth‐instar larvae of the spruce budworm
Authors: Panzuto M. , Albert P. J. 
Published: October 2003

AbstractAn electrophysiological approach was used to record the responses of maxillary styloconic sensilla of fourth‐ and sixth‐instar larvae of the spruce budworm Choristoneura fumiferana to 14 amino acids. One cell in the lateral styloconic sensillum was identified as an amino acid‐sensitive neuron. All of the amino acids tested, except l‐proline and l‐arginine, were detected by this cell. Arginine did not evoke a response from either the medial or lateral styloconic sensilla. Proline evoked responses from a cell in the medial styloconic sensillum. It is known from previous behavioural work that l‐proline is a phagostimulant and l‐valine inhibits feeding in Choristoneura; we thus further characterized the responses to these two amino acids. For both instars, l‐proline was detected as low as 0.001 mmol/l and the maximal response was at 50 mmol/l. Stimulation of fourth‐ and sixth‐instar larvae with l‐valine showed that the maximum firing frequency was obtained at 1 mmol/l. Above and below this concentration, firing frequency decreases. Sensory responses to the amino acids stimuli did not correlate with known behavioral responses to similar stimuli.
Wolbachia transmission in a naturally bi‐infected Drosophila simulans strain from New‐Caledonia
Authors: Merçot Hervé , Poinsot Denis 
Published: October 2003

Abstract Wolbachia are maternally‐transmitted endocellular bacteria infecting several arthropod species. In order to study the possibility of Wolbachia segregation in a naturally bi‐infected host, isofemale lines from a bi‐infected Drosophila simulans (Sturtevant) strain from Nouméa (New Caledonia) were backcrossed using uninfected males carrying the same nuclear background. Uninfected males were used to avoid the cytoplasmic incompatibility syndrome (CI) associated with the presence of Wolbachia in males. Each line was established using a female infected simultaneously by the two different Wolbachia variants wHa and wNo. The backcross led to some individuals carrying only one type of infection being recovered among the progeny of the bi‐infected foundress females. Rarely, uninfected individuals were also recovered. Isolated for the first time in its natural host, wNo exhibited a significantly weaker CI phenotype than the isolated wHa variant. Infection fate when backcross conditions were relaxed varied depending on rearing conditions of the host. Under favourable conditions, the infection was generally maintained, while it was frequently lost under unfavourable conditions. This result probably reflects the direct fitness dependence of the symbiont on its host.
Role of chlorophyll content of prey diets in prey‐locating behavior of a generalist predatory stink bug, Eocanthecona furcellata
Authors: Yasuda Tetsuya 
Published: October 2003

AbstractFeeding preferences of nymphs of a predatory stink bug, Eocanthecona furcellata, to Spodoptera litura larvae fed with various food items were examined. Bugs preferred larvae fed with spinach leaves to those feeding on bean sprouts. Solvent extracts of S. litura larvae given spinach or lettuce leaves contained a large amount of (E)‐phytol which was found to elicit the proboscis‐protruding behavior of this bug. (E)‐Phytol was not detected in similar extracts of larvae fed with bean sprouts containing no (E)‐phytol. When S. litura larvae fed with artificial diets containing various amounts of chlorophyll, the (E)‐phytol contents in those larvae and their feces increased in proportion to the dietary chlorophyll contents, indicating that (E)‐phytol was derived from the chlorophyll ingested through hydrolysis. Bugs showed the proboscis‐protruding behavior in response to extracts of larvae fed with spinach and lettuce leaves or a kidney‐bean artificial diet, and their response depended on (E)‐phytol contents. On the other hand, extracts of larvae fed with bean sprouts were not effective. When a larva fed with bean sprouts was treated with (E)‐phytol and presented together with a larva fed with spinach leaves, bugs failed to distinguish between the two. These results indicate that (E)‐phytol originating from chlorophyll in the prey diet serves as an important cue in the prey‐locating behavior of E. furcellata.
Effects of fumonisin B1 on growth and metabolism of larvae of the yellow mealworm, Tenebrio molitor
Authors: Abado‐Becognee K. , Fleurat‐Lessard F. , Creppy E.E. , Melcion D. 
Published: October 2003

AbstractThe chronic and acute toxicity of fumonisin B1 (FB1), a mycotoxin from Fusarium moniliforme, to the larvae of the yellow mealworm, Tenebrio molitor, was assessed. The toxin was administered via the diet or injected directly into the larvae. Young T. molitor larvae fed on a diet containing 450 μg FB1 per g diet exhibited reduced growth performance but only after consuming the fumonisin‐contaminated diet for several weeks. FB1‐contaminated diet also reduced the rate of carbon dioxide production, food consumption and protein metabolism. The concentrations of FB1 in the diet did not increase mortality, even when tested at the highest dose of 450 μg FB1 per g of diet. Injection of 25 ng FB1 per larva decreased the CO2 production, but became significant only 11 days after the injection and was reversible with time. A parallel analysis of the retention of FB1 by the larvae indicated that about 40% of the ingested FB1 was excreted in the faeces.
Effects of Pieris host species on life history parameters in a solitary specialist and gregarious generalist parasitoid (Cotesia species)
Authors: Brodeur Jacques , Geervliet Jacqueline B. F. , Vet Louise E. M. 
Published: October 2003

AbstractHost specificity and host selection by insect parasitoids are hypothesized to be correlated with suitability of the hosts for parasitoid development. The present study investigates the correlation between host suitability and earlier studied host‐finding behaviour of two closely related braconid larval parasitoid species, the generalist Cotesia glomerata (L.) and the specialist C. rubecula (Marshall) (Hymenoptera: Braconidae). We compared the capability of both parasitoid species to parasitize and develop in three Pieris host species, i.e. P. brassicae (L.), P. rapae (L.) and P. napi (L.) (Lepidoptera: Pieridae). In laboratory experiments, we measured the effect of host species on fitness parameters such as survival, development, sex ratio and size of parasitoid progeny. The results show that C. glomerata is capable of developing in the three host species, with significant differences in parasitoid survival, clutch size and adult weight among Pieris species. The host range for development was more restricted for C. rubecula. Although C. rubecula is physiologically able to develop in P. brassicae larvae, parasitoid fitness is negatively affected by this host species, compared to its most regular host, P. rapae. A comparison of the present data on host suitability with earlier studies on host‐searching behaviour suggests that the host‐foraging behaviour of both parasitoid species not only leads to selection of the most suitable host species for parasitoid development, but also plays a significant role in shaping parasitoid host range.
Plant architecture and the foraging success of ladybird beetles attacking the Russian wheat aphid
Authors: Clark Teresa L. , Messina Frank J. 
Published: October 2003

AbstractWe examined the interaction between the fourteen‐spotted ladybird beetle, Propylea quatuordecimpunctata (L.), and the Russian wheat aphid, Diuraphis noxia (Mordvilko), on two grasses with divergent leaf architectures. Like wheat, crested wheatgrass bears flat, broad leaves, whereas Indian ricegrass produces slender, tightly rolled leaves. In the absence of aphid prey, residence times and time budgets of larvae and adults of P. quatuordecimpunctata were similar on the two hosts, although larvae tended to remain longer on crested wheatgrass. When aphids were present, both predator stages dislodged, contacted, and captured aphids at higher rates on Indian ricegrass than on crested wheatgrass. Predator time budgets and behavior sequences also reflected a greater predation risk for D. noxia on Indian ricegrass, and were consistent with earlier, population‐level experiments in the field. Comparisons between aphid‐free and aphid‐infested plants suggest that the effect of host plant in this tri‐trophic system largely depended on differences in the availability of prey refuges rather than on differences in predator searching behavior; proportionally more aphids fed in exposed locations on Indian ricegrass than on crested wheatgrass. Plant architecture is likely to be an important component of the predation risk of D. noxia because of the aphid's tendency to feed in relatively concealed locations.
Sensitivity of two greenhouse pests to vapours of essential oils
Authors: Tunç I. , Şahinkaya Ş. 
Published: October 2003

AbstractVapours of essential oils extracted from cumin, Cuminum cyminum L., anise, Pimpinella anisum L., oregano, Origanum syriacum var bevanii (Holmes) Ietswaart and eucalyptus, Eucalyptus camaldulensis Dehn., were found to be toxic to two greenhouse pests, viz. the carmine spider mite, Tetranychus cinnabarinus (Boisd.) (Tetranychidae, Tetranychini) and cotton aphid, Aphis gossypii Glov. (Aphididae, Aphidini). In general, a minimum dose of 0.5 μl/l air and 2–3 days of exposure was required for 99% mortality using essential oils of the first three plants.
Effects of prey density, prey instar, and patch size on the development of the predatory mosquito, Toxorhynchites towadensis
Authors: Yasuda Hironori , Hagimori Kyoko 
Published: October 2003

AbstractEffects of prey density, prey instar, and patch size on the development of the predatory mosquito larva, Toxorhynchites towadensis, were investigated in the laboratory. Survivors of T. towadensis showed different developmental patterns in relation to prey age structure. All predatory larvae in containers with only second instar prey developed into the third instar. However, in several containers with fourth instar prey, mortality of predators was observed. During the third instar, no predatory larva died, but both prey density and prey instar significantly affected the survival of predators during their fourth instar. Large prey size promoted large predator adults, and predatory larvae which grew up in small surface containers responded by developing to large sizes than those in large containers. Larval developmental time of the predators differed in each treatment. During first and second instars, faster predator development was observed in containers with small surface areas and containing young prey individuals. However, when development was enhanced by the presence of old prey individuals, no surface effect was observed. The fastest predator development was observed with prey of mixed instars and high density. This study suggests that a small surface container containing prey of mixed instars and high density is suitable for development of predators.
Plant virus and parasitoid interactions in a shared insect vector/host
Authors: Christiansen‐Weniger Petra , Powell Glen , Hardie Jim 
Published: October 2003

AbstractInteractions between barley yellow dwarf luteovirus (BYDV) and the aphid parasitoid, Aphidius ervi Haliday (Hymenoptera: Aphidiidae), were investigated while sharing the vector/host, Sitobion avenae (F.) (Homoptera: Aphididae). Aphids, which were parasitized during their second larval stadium, had access to virus‐infected plants before, immediately after, or several days after parasitoid attack. The larval development of A. ervi in S. avenae was significantly delayed when virus acquisition took place before or shortly after the parasitoid had hatched, but not when the parasitoid was at the second larval stage during virus acquisition. Similarly, the presence of BYDV led to a significantly higher aphid mortality when they acquired virus up to and including the time that A. ervi was at the first larval stage. Adult female parasitoids deposited fewer eggs in viruliferous aphids. Virus transmission was not reduced by parasitization, and in some experiments aphids which were subjected to parasitoid attack transmitted BYDV more efficiently than unattacked insects.
Infochemicals influencing the host foraging behaviour of Dahlbominus fuscipennis, a pupal parasitoid of the European spruce sawfly (Gilpinia hercyniae)
Authors: Rostás Michael , Dippel Cornelia , Hilker Monika 
Published: October 2003

AbstractThe chalcidoid wasp Dahlbominus fuscipennis Zett. (Hymenoptera: Eulophidae) parasitises pupae of the European spruce sawfly Gilpinia hercyniae Htg. (Hymenoptera: Diprionidae). In this parasitoid‐host system the role of infochemicals for successful parasitisation was studied. Olfactometer experiments and dual choice bioassays in petri dishes showed that D. fuscipennis was not attracted by volatiles from a plant‐host complex consisting of spruce, sawfly larvae and pupae. On the other hand, odours from needles of Picea abies (L.), that were collected from the ground, attracted D. fuscipennis to the habitat of the sawfly. Volatiles from host pupae were not attractive, whereas a contact kairomone from sawfly pupae elicited frequent antennal drumming, a behaviour that indicates host recognition. This contact kairomone was extracted with methanol from the outer cocoon layer of the pupa. The kairomone is not produced by the silk glands of the last instar larva spinning the cocoon, since a methanolic extract of silk gland secretion did not elicit any response in D. fuscipennis. Further bioassays revealed that non‐volatile components of the integument of the prepupa within the cocoon also elicited antennal drumming. We suggest that chemicals of the prepupal integument diffuse from inside the cocoon to the outside where they inform the parasitoid on the suitability of the host.
Control of codling moth in small plots by mating disruption: alone and with limited insecticide
Authors: Vickers R. A. , Thwaite W. G. , Williams D. G. , Nicholas A. H. 
Published: October 2003

AbstractMating disruption alone and mating disruption supplemented with limited applications of either azinphos‐methyl or fenoxycarb was evaluated in 0.11–0.30 ha plots for the control of codling moth Cydia pomonella (L.) (Tortricidae: Olethreutinae) populations.Where populations were low, mating disruption alone was sufficient to keep codling moth damage levels below 1% at harvest. ‘Low’ was defined as no more than 0.2% damage at harvest and fewer than 1.3 larvae/metre of trap band from January–March inclusive in the previous season. Neither mating disruption alone nor when supplemented with azinphos‐methyl or fenoxycarb during the first spring generation gave commercially acceptable levels of control in other than low density populations. Small plot size may have contributed to the failures.At the high density site unintentional supplementary control provided by drift of azinphos‐methyl from border areas to which it was applied throughout the season gave excellent control in the first year and suggested an interaction between low dosages of insecticide and pheromone treatments that enhanced the disruptive effect of the latter.
Stimulation and attenuation of induced resistance by elicitors and inhibitors of chemical induction in tomato (Lycopersicon esculentum) foliage
Authors: Stout Michael J. , Workman Kathi V. , Bostock Richard M. , Duffey Sean S. 
Published: October 2003

AbstractElicitors and inhibitors of chemical induction were used to manipulate the activities of several putative defense‐related proteins in leaves of the tomato, Lycopersicon esculentum Mill. The four presumptive defenses manipulated were proteinase inhibitors, polyphenol oxidase, peroxidase, and lipoxygenase. The elicitors used were jasmonic acid, methyl jasmonate, ultraviolet light, and feeding by larvae of the noctuid, Helicoverpa zea Boddie; the inhibitors used were salicylic acid and acetylsalicylic acid. These chemical manipulations were combined with short‐term growth assays using larvae of the generalist noctuid, Spodoptera exigua Hubner, in order to assess the relative roles of the proteins in induced resistance to S. exigua. When activities of proteinase inhibitors and/or polyphenol oxidase in leaf tissue were high (e.g., in damaged or elicited plants), growth rates of larvae of S. exigua were low; when activities of polyphenol oxidase and proteinase inhibitors were low (e.g., in undamaged or damaged, inhibited plants), growth rates of larvae were high. In contrast, high activities of peroxidase and lipoxygenase were not associated with decreases in suitability of leaf tissue for S. exigua. The association of high levels of proteinase inhibitors and polyphenol oxidase with resistance to S. exigua– irrespective of the presence or absence of damage – strongly implicates these proteins as causal agents in induced resistance to S. exigua.
Electroantennogram responses of male Sphinx perelegans hawkmoths to floral and ‘green‐leaf volatiles’
Authors: Raguso Robert A. , Light Douglas M. 
Published: October 2003

AbstractElectroantennograms (EAGs) from field‐collected male Sphinx perelegans hawkmoths were recorded in response to 10 individual floral scent compounds identified from Clarkia breweri (Onagraceae), 21 additional volatiles characteristic of other night‐blooming flowers, and eight ‘green leaf’ volatiles. Measurable EAG responses were elicited to all compounds tested, but the most effective antennal stimulants were benzyl acetate, linalool, methyl salicylate and trans‐2‐hexenal. Mean, pooled EAGs to oxygenated terpenoids, aromatic esters and fatty acid derivatives were larger in magnitude than those in response to aromatic aldehydes/alcohols, monoterpenes and nitrogen‐bearing compounds. The rank order of male S. perelegans' EAGs did not differ significantly from that of previously recorded responses of male Hyles lineata to the same scent compounds, and EAG magnitudes were generally larger for S. perelegans than for H. lineata. Both hawkmoth species are shown to have broad olfactory receptivities and could potentially respond to a wide array of plant volatiles as floral attractants.
Behavioural and olfactory variations in the leek moth, Acrolepiopsis assectella, after several generations of rearing under diverse conditions
Authors: Lecomte C. , Pierre D. , Pouzat J. , Thibout E. 
Published: October 2003

AbstractThree strains of the leek moth, Acrolepiopsis assectella, were compared: two reared on leek leaves (Allium porrum) for which generations 10 to 12 (L) or generation 2 (G2) were used, the third one (D) reared on an artificial diet incorporating leek powder, for which generation ca 140 was examined. The walking behaviour (L and D) and the antennal responsiveness (L, G2 and D) were compared between individuals subjected to leek leaf odour and 4 volatiles identified in these leaves: 2 specific sulphur ones (dipropyl thiosulphinate and dipropyl disulphide) and 2 ‘general green leaf volatiles’ (cis‐3‐hexen‐1‐ol and trans‐2‐hexen‐1‐ol). The walking behavioural thresholds to leek odour, dipropyl thiosulphinate, and cis‐3‐hexen‐1‐ol were lower for L than for D females. The chemoanemotactic responses to dipropyl disulphide are almost identical, and trans‐2‐hexen‐1‐ol has nearly no activity. Accordingly, the olfactory sensitivity (assessed by EAG) to sulphur volatiles and cis‐3‐hexen‐1‐ol was higher for L and G2 females than for D ones. The threshold for thiosulphinate was at a concentration (v/v) of 4 ×10−4 M/l for D females, 4 × 10−5 M/l for L females and 4 × 10−8 M/l for G2 ones. It may be hypothesised that laboratory rearing conditions cause variations in the thresholds of antennal sensitivity and walking behaviour to specific and more efficient leek volatiles. This may result from the selective pressures experienced by the larvae reared in the laboratory.
Identification of the sex pheromone of Ostrinia palustralis
Authors: Huang Yongping , Tatsuki Sadahiro , Kim Choon‐gon , Hoshizaki Sugihiko , Ishikawa Yukio 
Published: October 2003

AbstractBy means of gas chromatography with electroantennographic detection, gas chromatography‐mass spectrometry and a series of bioassays, (E)‐11‐tetradecenyl acetate (E11‐14:OAc) and (Z)‐11‐tetradecenyl acetate (Z11‐14:OAc) at a ratio of 99:1 were identified as female sex pheromone components of Ostrinia palustralis. The average amounts of E11‐ 14:OAc and Z11‐14:OAc in a single sex pheromone gland were 37.2±24.4 ng and 0.3±0.2 ng, respectively. In a wind‐tunnel bioassay, the binary blend of E11‐ and Z11‐14:OAc elicited the same male behavioral responses as did virgin females.