bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host preferences of two encyrtid parasitoids for the Columbian Phenacoccus spp. of cassava mealybugs
Authors: Van Driesche R. G. , Bellotti A. , Herrera C. J. , Castillo J. A. 
Published: April 2011

AbstractIn a choice test among six life stages of Phenacoccus herreni Cox & Williams, Epidinocarsis diversicornis (Howard) used its antennae to examine adult and 3rd stadium females more than other stages and preferentially attempted to oviposit in these plus 2nd stadium females. Success of ovipositor insertion was unaffected by host stage. The outcome of these behaviors was preferential oviposition by E. diversicornis in the large female host stages. Acerophagus coccois Smith also preferentially examined larger female mealybugs (second and third stadium nymphs and adults) more than other stages and successfully inserted its ovipositor in these stages more often than in second stadium male nymphs and male cocoons, resulting in a similar preference in this species for larger female host stages. When given a choice between adult female hosts of two species, P. herreni and Phenacoccus gossypii Townsend & Cockerell, E. diversicornis exhibited a clear preference for P. herreni; whereas A. coccois preferred P. gossypii.RÉSUMÉChoix opéré par deux encyrtides parasitoïdes parmi des espèces colombiennes de Phenacoccus, cochenilles du maniocEpidinocarsis diversicornis (Howard), ayant la possibilité de choisir entre six stades différents de Phenacoccus herreni Cox & Williams, examine avec ses antennes plus particulièrement les adultes et les larves femelles du 3ème stade, et essaie de pondre de préférence dans ces stades et les larves femelles de second stade. L'insertion de la tarière s'effectue aussi bien quel que soit le stade de l'hôte. Il résulte de ces différents aspects du comportement que E. diversicornis pond de préférence dans les femelles des stades les plus avancés. Acerophagus coccois Smith préfère aussi examiner les cochenilles femelles les plus grosses (second et 3ème stade larvaires et adulte), et introduit sa tarière avec succès dans ces stades plus souvent que dans les larves mâles de second stade ou les cocons mâles; il en résulte aussi pour cette espèce une préférence pour les femelles des stades les plus gros.Quand on leur a donné le choix entre des femelles des deux espèces de cochenilles (P. herreni et Phenacoccus gossypii Towsend & Cockerell), E. diversicornis manifestait une nette préférence pour P. herreni, tandis que A. coccois préférait P. gossypii.
The contribution of symbiotic yeast to toxin resistance of the cigarette beetle (Lasioderma serricorne)
Authors: Dowd Patrick F. , Shen Samuel K. 
Published: April 2011

AbstractRepresentative plant allelochemicals were tested for toxicity to larvae of the cigarette beetle Lasioderma serricorne (F.) that were either untreated, treated with fungicides, or treated to render them free of symbiotic yeast (‘aposymbiotic’) through surface sterilization of eggs. Insects rendered symbiont‐free had higher mortality and/or developmental rates than controls when fed diets containing flavone, resorcinol or tannic acid. Fungicides reduced symbiont populations and/or caused morphological abnormalities. Two hydrolytic enzymes, which made up a significant portion of mycetome hydrolytic activity, were absent when symbionts were not present, as indicated by gel electrophoresis. This information indicates symbionts do contribute to the survival of their host by detoxifying toxins.RésuméContribution des levures symbiotiques à la résistance de Lasioderma serricorne aux toxinesLa toxicité relative de substances allélochimiques végétales typiques a été examinée sur des larves de L. serricorne F. traitées aux fongicides et rendues aposymbiotiques par stérilisation superficielle des œufs. La toxicité de la nicotine est relativement inaffectée chez les larves aposymbiotiques; cependant les toxicités des resorcinol, flavone et acide tannique sont significativement augmentées chez les insectes ayant reçu un traitement pour éliminer leurs symbiontes. L'électrophorèse sur gel a montré que quelques enzymes responsables de l'hydrolyse du 1‐naphthyl acétate, réaction enzymatique de la détoxification enzymatique, sont absentee chez les insectes aposymbiotiques. L'acide sorbique a réduit significativement l'effectif de symbiontes, tandis que le bénomyl a réduit leur gamme provoquant la multiplication anormale d'autres espèces. Ces résultats montrent que les symbiontes contribuent aux possibilités de détoxification de l'insecte. L'élimination des symbiontes peut être une technique efficace pour lutter contre les insectes qui en contiennent, puisqu'elle les priverait de leur contribution à l'alimentation et à la détoxification. Cette stratégie est vraisemblablement compatible avec des programmes de lutte intégrée, puisque les prédateurs et parasites ne contiennent pas de symbiontes.
Responses of the parasitoid Cotesia rubecula to its host Pieris rapae in a flight tunnel
Authors: Keller Michael A. 
Published: April 2011

AbstractResponses of female Cotesia rubecula (Marshall) (Hymenoptera: Braconidae) to larval Pieris rapae (L.) (Lepidoptera: Pieridae) feeding on cabbage leaves were investigated in a flight tunnel. Latency of flight was shorter and the proportion of female wasps flying to leaves was greater when cabbage was infested with hosts. This indicated that wasps detected hosts prior to taking flight and were attracted to them. Wind speed was varied (18, 54, 100 cm/s) to examine its effect on the response of wasps to hosts. Flight was inhibited by increasing wind speed and was accompanied by less frequent but longer bouts of ‘pointing’ (antennae raised and spread, facing into the wind). The accuracy of landing but not the duration of flight to the plant was affected by increasing wind speed. The results indicated that increasing wind speed will reduce the rate of parasitoid oviposition.RésuméRéactions dans un tunnel de vol du parasitoïde Cotesia rubecula à son hôte, Pieris rapaeCette étude concerne les réactions des femelles de C. rubecula Marshall (Hyméno., Braconidae) aux chenilles de P. rapae (Lépido, Pieridae) alimentées sur feuilles de choux. Le tunnel fournit un flux laminaire et l'air est recyclé avec désodorisation par circulation sur un filtre de charbon de bois. La période de latence avant l'envol est plus brève et la proportion de femelles volant vers les feuilles plus élevée quand les choux sont contaminés par les chenilles. Ceci montre que les femelles détectent les hôtes avant l'envol et qu'ils les attirent. Le vent peut influer sur la libération de kairomones, sur les caractéristiques du panache d'odeurs et sur l'énergétique du vol; en conséquence, différentes vitesses de vent (18, 54, 100 cm/S) ont été utilisées pour examiner leurs effets sur la réaction des braconides. Le vol a été inhibé par une augmentation de la vitesse du vent et était accompagné par de plus longues, mais moins fréquentes poussées de ‘pointage’ (antennes dressées et étendues, face au vent). La précision de l'atterrissage a été affectée par l'augmentation de la vitesse du vent, mais non la durée du vol vers la plante. Ces résultats ont montré que l'augmentation de la vitesse du vent peut réduire le taux de ponte du parasitoïde en inhibant le vol. La signification de ces résultats est discutée en relation avec la situation dans la nature.
Oviposition and tarsal chemoreceptors of the cabbage root fly are stimulated by glucosinolates and host plant extracts
Authors: Roessingh P. , Städler E. , Fenwick G. R. , Lewis J. A. , Nielsen J. Kvist , Hurter J. , Ramp T. 
Published: April 2011

AbstractThe role of glucosinolates in the oviposition behaviour of the cabbage root fly, Delia radicum (L.) (Diptera, Anthomyiidae) was investigated using egg counts and electrophysiological recordings from tarsal contact chemoreceptors. The glucosinolates present both inside and on the surface of cauliflower leaves were determined. The total amounts obtained with the two methods differed by a factor of 100. The extract of the leaf surface contained about 60 μg per g leaf extracted (gle), the total leaf extract 7.5 mg per gle. The glucosinolate patterns of the two extracts were qualitatively similar, but the ratios of the content of individual glucosinolates showed considerable differences.The D sensilla on segment 3 and 4 of the tarsus of D. radicum females were shown to contain a sensitive receptor cell for glucosinolates. In contrast, the receptor cells of the D sensilla of the other segments did not respond in a dose dependent way to these compounds. The glucosinolate receptors were found to be especially sensitive to glucobrassicin, gluconasturtiin and glucobrassicanapin with thresholds of about 10 −8M to 10 −9M. Large differences (up to two orders of magnitude) were observed among the different glucosinolates.A significant correlation was found between the behavioural discrimination index and the electrophysiological results. But no obvious correlation existed between the chemical nature of the glucosinolate side chain (e.g. indole, aromatic and aliphatic groups), and their stimulatory activity. However, a significant correlation was found between the overall length of the side chain and the biological activity.Although the flies discriminated clearly between model leaves with and without glucosinolates, a clear dose response curve was only obtained for the indole glucosinolate glucobrassicin. Since the most stimulatory fraction of the surface extract contained no glucosinolates, it was concluded that other compounds, in addition to glucosinolates, do play an important role for the stimulation of oviposition.
Effects of diet, photoperiod and temperature on the postdiapause reproduction in the cabbage bug, Eurydema rugosa
Authors: Ikeda‐Kikue K. , Numata H. 
Published: April 2011

AbstractIn Eurydema rugosa Motschulsky (Heteroptera: Pentatomidae), the type of food supplied (i.e. seeds or leaves of the brown mustard, Brassica juncea Hemsel) and photoperiod, which control the induction of adult diapause, do not play a role in the initiation of reproduction after overwintering. A temperature above 13.2°C was required to start reproduction. After its initiation, however, short‐day conditions on seeds induced diapause again in some adults. Although a diet of seeds under long‐day conditions, in common with short‐day conditions, induced diapause in young adults (Numata & Yamamoto, 1990), it did not reinduce diapause in adults after overwintering. Thus, E. rugosa that had overwintered became sensitive to diapause‐inducing photoperiod again but not to dietary factors.
The effect of host size on quality attributes of the egg parasitoid, Trichogramma pretiosum
Authors: Bai Baorong , Luck Robert F. , Forster Lisa , Stephens Beth , Janssen J. A. M. 
Published: April 2011

AbstractIn a study of the quality of Trichogramma pretiosum Riley (Hymenoptera: Trichogrammidae), we compared female wasps emerging from natural hosts, parasitized in the laboratory or the field with those emerging from factitious hosts used for commercial mass production. Females from the natural hosts were larger, more fecund, and longer lived than those from the factitious hosts. Compared to small females, large female wasps are substantially more fecund when honey (carbohydrate) is available but marginally more fecund when honey is unavailable. The size of a female T. pretiosum depends on two factors: the size of the host egg from which it emerges even when the wasp was gregarious, and the number of conspecifics that emerge with it. The similarities in the size distribution of female wasps emerging from natural hosts, in conjunction with the mechanism by which Trichogramma measure host size and allocate eggs accordingly, suggests the hypothesis that size related components of fitness in female T. pretiosum are under strong selection in the field.
Effect of dietary nitrogen on gypsy moth larval nutritional indices, development and lipid content
Authors: Sheppard C. A. , Friedman S. 
Published: April 2011

AbstractNutritional indices, development rates, percent dry weights and total lipids were determined in gypsy moth larvae (Lymantria dispar L.) reared on a high wheat germ (HWG) diet or diets prepared from lyophilized, ball‐milled oak or pine foliage as the only source of dietary nitrogen (N). With regard to both total and proteinaceous N content, HWG diet > oak diet > pine diet. All nutritional indices measured were significantly lower in second instars fed pine diet vs. oak diet. Protein supplementation of pine diet with either casein or ovalbumin to bring total N up to the level present in oak diet resulted in small increases in approximate digestibility (AD) and efficiency of conversion of ingested food (ECI), but relative growth rate (RGR) remained unaffected. The low RGR of larvae fed pine diet (unsupplemented or protein supplemented), as compared to those fed HWG or oak diet, was accompanied by significantly lower larval percent dry weight and percent total lipid. In contrast, RGR, larval percent dry weight and total lipid values were comparable in second instars fed HWG or oak diet. Insects reared from the first through the final instar on oak diet exhibited lower pupal weights compared to those reared on HWG. Casein addition to oak diet generally resulted in even more extended larval development times and further reduced pupal weights, but wheat germ addition to oak diet did not alter development rates and caused an increase in pupal weights.
Prospects for using pyroproxyfen‐treated targets for tsetse control
Authors: Langley P. A. , Hargrove J. W. , Mauchamp B. , Royer C. , Oouchi H. 
Published: April 2011

AbstractUsing 14C cholesterol as a marker a positive correlation was established between the amount of oil (a chlorinated n‐alkane containing 43–46% chlorine, ‘cereclor S45’) picked up by an adult tsetse fly exposed by tarsal contact to a treated surface and the duration of such exposure. Only a poor uptake was achieved from netting surfaces treated with less than 50% oil in acetone. Terylene netting treated with radioactive pyriproxyfen, [1‐methyl‐2‐(4‐phenoxyphenoxy)ethoxy] pyridine, dissolved in cereclor, was exposed in the field for a year. After 9 months 20 % of the original radioactivity remained and was shown to be 95% authentic pyriproxyfen. Brief tarsal contact (up to 5 seconds) with such netting, by adult females of Glossina morsitans morsitans Westwood, reduced the viability of their offspring to 28–43% of untreated control values. The effect was greatest in the reproductive cycle immediately following contact. Between 10 and 12 months after treatment of the fabric the radioactivity fell to only 7% of the original level but was associated mainly (>80%) with intact pyriproxyfen. Exposure of female flies to this netting resulted in a positive correlation between the duration of exposure and the extent of suppression of offspring viability, such that 2 min was sufficient to reduce offspring viability to zero for the life of the female. Traps or targets impregnated with conventional formulations of pyrethroids to kill tsetse would have lost all their activity by this time. Results are discussed in terms of the prospects for using pyriproxyfen‐treated targets to sterilize female tsetse directly and also indirectly through the contamination of males prior to mating through contact with such targets.
Survival of the parasitoid Encarsia formosa after treatment of parasitized greenhouse whitefly larvae with fungal spores of Aschersonia aleyrodis
Authors: van Lenteren Joop C. , Fransen Joanne J. 
Published: April 2011

AbstractThe interaction between the entomopathogenic fungus Aschersonia aleyrodis and the parasitoid Encarsia formosa on greenhouse whitefly as a host organism was studied, in particular, the survival of the parasitoid after treatment of parasitized hosts with fungal spores. The mean number of parasitized black pupae per parasitoid produced at 25°C was significantly reduced after spore treatment in the first three days following parasitization. Spore treatment four, seven or ten days after parasitization resulted in a mean number of parasitized pupae not significantly different from the number of black pupae in the control. The rather sudden change from low to high survival of parasitized hosts when treated with spores four days after parasitization in spite of high numbers of infected unparasitized larvae, coincided with the hatching of the parasitoid larva from the egg inside the host. Possible reasons for this decrease in susceptibility to infection after parasitoid egg hatch, such as induced changes in host cuticle or haemolymph, are discussed. Parasitoids emerged from treated hosts did not show differences in reproduction compared with parasitoids emerging from untreated hosts. Both natural enemies of whitefly are compatible to a great extent.
Adaptive significance of wing dimorphism in males of Nilaparvata lugens
Authors: Novotný V. 
Published: April 2011

AbstractThe trade‐offs associated with macroptery in males were investigated in a wing‐dimorphic planthopper, Nilaparvata lugens (Stål) (Delphacidae, Hemiptera). Developmental time of brachypters was significantly shorter than that of macropters across a wide range of population densities, while no within‐population differences between wing morphs in body weight were found. In mating experiments, brachypterous males 12 to 24 h old were almost three times more successful in competition for females than macropterous males of the same age, while in five days old males, macropters were twice as successful as brachypters. In competition for females involving direct body contact between males, brachypterous and macropterous males were equally successful. It is suggested that macroptery and delayed peak in sexual activity in males may both be influenced by the titre of juvenile hormone, as is known from females. The combination of prolonged development and delayed maximum competitive ability for mates, associated with macroptery, is likely to be disad vantageous, representing probably a penalty associated with macroptery in males in undisturbed habitats.
Effects of Maternal Exposure to Cow's Milk High or Low in Isoflavones on Carcinogen-Induced Mammary Tumorigenesis among Rat Offspring
Authors: Nielsen Tina Skau , Purup Stig , Wärri Anni , Godschalk Roger W. , Hilakivi-Clarke Leena 
Published: April 2011

Abstract
We investigated whether maternal exposure during pregnancy to cow's milk containing endogenous estrogens and insulin-like growth factor 1 (IGF-1) and either high or low levels of isoflavones from dietary legumes (HIM and LIM, respectively) affected carcinogen-induced mammary carcinogenesis in female rat offspring. Pregnant Sprague-Dawley rats were given HIM, LIM, or tap water (control) from gestational day (GD) 11 until birth; hereafter all rats received tap water. Mammary tumorigenesis was induced by administrating 7,12-dimethylbenz[a]anthracene (DMBA) on postnatal day 50. No differences in maternal serum estradiol (P = 0.19) and IGF-1 levels (P = 0.15) at GD 19 or birth weight among the milk and water groups were seen, but estradiol, and IGF-1 levels and birth weight were numerically higher in the LIM group than in the HIM group. Puberty onset occurred earlier in the LIM offspring than in controls (P = 0.03). Although the high isoflavone content seemed to prevent the effect on circulating estradiol and IGF-1 levels and advanced puberty onset seen in the LIM group, HIM increased DMBA–DNA adducts in the mammary gland and tended to increase mammary tumorigenesis. In contrast, offspring exposed to LIM in utero, did not exhibit increased breast cancer risk, despite having higher estradiol and IGF-1 environment and consequently earlier puberty onset. These results indicate that the phytochemical content in the cow's milk, consumed by a pregnant dam, determines how milk affects the offspring. Cancer Prev Res; 4(5); 694–701. ©2011 AACR.
Simple two-step fabrication method of Bi2Te3 nanowires
Authors: Kang Joohoon , Noh Jin-Seo , Lee Wooyoung 
Published: April 2011

AbstractBismuth telluride (Bi2Te3) is an attractive material for both thermoelectric and topological insulator applications. Its performance is expected to be greatly improved when the material takes nanowire structures. However, it is very difficult to grow high-quality Bi2Te3 nanowires. In this study, a simple and reliable method for the growth of Bi2Te3 nanowires is reported, which uses post-sputtering and annealing in combination with the conventional method involving on-film formation of nanowires. Transmission electron microscopy study shows that Bi2Te3 nanowires grown by our technique are highly single-crystalline and oriented along [110] direction.
Electromagnetic modeling of waveguide amplifier based on Nd3+ Si-rich SiO2 layers by means of the ADE-FDTD method
Authors: Dufour Christian , Cardin Julien , Debieu Olivier , Fafin Alexandre , Gourbilleau Fabrice 
Published: April 2011

AbstractBy means of ADE-FDTD method, this paper investigates the electromagnetic modelling of a rib-loaded waveguide composed of a Nd3+ doped Silicon Rich Silicon Oxide active layer sandwiched between a SiO2 bottom cladding and a SiO2 rib. The Auxilliary Differential Equations are the rate equations which govern the levels populations. The Finite Difference Time Domain (FDTD) scheme is used to solve the space and time dependent Maxwell equations which describe the electromagnetic field in a copropagating scheme of both pumping (λ
pump
= 488 nm) and signal (λ
signal
= 1064 nm) waves. Such systems are characterized by extremely different specific times such as the period of electromagnetic field ~ 10-15 s and the lifetimes of the electronic levels between ~ 10-10s and ~ 10-4 s. The time scaling method is used in addition to specific initial conditions in order to decrease the computational time. We show maps of the Poynting vector along the propagation direction as a function of the silicon nanograin (Si-ng) concentrations. A threshold value of 1024 Si-ng m-3 is extracted below which the pump wave can propagate so that a signal amplication is possible.
Carbon Fiber Reinforced Rigidizable Space Structures
Authors: Sarles Stephen Andrew , Bullions Todd , Mefford Thompson , Riffle Judy , Leo Don 
Published: April 2011

ABSTRACTIn attempts to provide an active solution for the rigidization of flexible space structures, internal resistive heating is applied to a novel thermosetting resin. Carbon-fiber tow coated in U-Nyte Set 201A, which cures at ∼150°C, was heated by passing electric current through the reinforcing material. Using a proportional-integral (PI) controller, precise temperature control of the heating process was established. Samples cured via controlled internal resistive heating were heated to 160°C and underwent material consolidation in less than 7 minutes. A change in material stiffness was measured to be almost two orders of magnitude greater than that of an uncured material.
The Crystalline and Dielectric Properties of 0.38(Bi1−xLax)ScO3-0.62PbTiO3 Ferroelectric Ceramics
Authors: Chen Yi , Lan Dejun , Chen Qiang , Xu Zhuo , Yue Xi , Xiao Dingquan , Zhu Jianguo 
Published: April 2011

ABSTRACTTo investigate the effects of partially substitution of lanthanum for bismuth in the BiScO3-PbTiO3 (BSPT) ceramics, the 0.38(Bi1−xLax)ScO3-0.62PbTiO3 (BLSPTx) ceramics were prepared by using conventional solid state process. It was found that the partial replacement of lanthanum for bismuth do not affects the crystalline structure of the BSPT ceramics. With increasing of the lanthanum content, the grains of BLSPTx ceramics grown much bigger than those of BSPT ceramics when BLSPTx and BSPT ceramics were sintered at the same temperature. The temperature dependence of dielectric permittivity of BLSPTx ceramics shows that the Curie temperature (Tc) shifts toward lower temperature with the increasing of lanthanum content, and the BLSPTx samples for x=0.02 show the highest value of the dielectric constant at Tc.