bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rates of growth and increase of Myzus persicae on virus‐infected potatoes according to type of virus‐vector relationship
Authors: Castle S. J. , Berger P. H. 
Published: April 2011

AbstractGrowth, reproduction and survival (= performance) of the aphid Myzus persicae Sulzer was measured on virus‐free and virus‐infected potato plants. The principle objective was to evaluate if various viral infections affected aphid performance differently, and if so, whether any order in the performance response of the aphid was discernible according to the type of virus‐vector relationship. Three viruses varying in their dependency on M. persicae as a vector were used. Plants infected with potato leafroll virus (PLRV), a circulative virus highly dependent upon M. persicae for dispersal and transmission, were superior hosts as determined by the significantly greater mean relative growth rate (MRGR) and intrinsic rate of increase (rm) of M. persicae compared with those of aphids reared on other plants. Plants infected with potato virus Y, a noncirculative virus less dependent upon M. persicae for dispersal than PLRV, were intermediate in their quality based upon intermediate MRGR and rm values. Plants infected with potato virus X, a nonvectored virus independent of M. persicae, were least suitable hosts along with the group of virus‐free plants according to the lower MRGR and rm values.
Avidin and streptavidin as insecticidal and growth inhibiting dietary proteins*
Authors: Morgan T. D. , Oppert B. , Czapla T. H. , Kramer K. J. 
Published: April 2011

AbstractAvidin was found to be an insecticidal and growth inhibiting dietary protein for five species of Coleoptera (red flour beetle, Tribolium castaneum, confused flour beetle, T. confusum, sawtoothed grain beetle, Oryzaphilus surinamensis, rice weevil, Sitophilus oryzae, and lesser grain borer, Rhyzopertha dominica) and two species of Lepidoptera (European corn borer, Ostrinia nubilalis, and Indianmeal moth, Plodia interpunctella). At levels ranging from 10 to 1000 ppm in the diet depending on the species, avidin retarded the growth and caused mortality of all seven species. Addition of biotin to the avidin‐treated diets for T. castaneum, T. confusum, R. dominica, and O. nubilalis prevented the growth inhibition and mortality caused by avidin. Streptavidin exhibited similar insecticidal and growth inhibiting activity towards T. castaneum and O. nubilalis. The results support the hypothesis that feeding avidin or streptavidin to insects causes a biotin deficiency which in turn leads to stunted growth and mortality. Avidin and streptavidin are insect growth inhibiting proteins whose genes potentially could be manipulated into plants and provide host plant resistance to insect pests.
Response of the parasitoid Eupelmus vuilleti to the odours of the phytophagous host and its host plant in an olfactometer
Authors: Cortesero A. M. , Monge J. P. , Huignard J. 
Published: April 2011

AbstractEupelmus vuilleti (CRW) is a solitary ectoparasitoid which, under our experimental conditions, developed at the expense of the larvae and pupae of Bruchidius atrolineatus (Pic) (Coleoptera, Bruchidae). The larvae of this beetle are found inside the seeds of cowpea, Vigna unguiculata (Walp). Using a tubular olfactometer, we determined the olfactory stimuli involved in the orientation of females of the hymenopterous species E. vuilleti towards one of its hosts; B. atrolineatus. Several odours were tested including those from host plants of B. atrolineatus, from non‐host plants, from the host itself and from the waste products of the host. The odours of pods or dry seeds of V. unguiculata (host plant of the phytophagous insect) affected the locomotor behaviour of females of E. vuilleti. The odours from the plant in the vegetative stage had no effect. Kairomones from larvae, pupae or faeces of B. atrolineatus were attractive to the parasitoid females. Odours from adult male or female B. atrolineatus, as well as the sex pheromone emitted by females were not attractive to E. vuilleti females. This sex pheromone did however stimulate the locomotor activity of the parasitoid. The adaptive significance of these olfactory stimuli is discussed.RésuméRéponse du parasitoïde Eupelmus vuilleti aux odeurs de son hôte phytophage et de la plante‐hôte dans un olfactomètreEupelmus vuilleti (CRW) est un ectoparasitoïde solitaire qui se développe dans nos conditions expérimentales aux dépens des larves et des nymphes de Bruchidius atrolineatus (Pic) (Coléoptère: Bruchidae). Les larves de ce Coléoptère se trouvent à l'intérieur des graines d'une Légumineuse Vigna unguiculata (Walp). Grâce à un olfactomètre tubulaire, nous avons déterminé les différents stimuli olfactifs intervenant dans l'orientation des femelles de cet hyménoptère, vers l'un de ses hôtes; Bruchidius atrolineatus. Plusieurs odeurs émanant soit de plantes‐hôtes ou non‐hôtes de B. atrolineatus, soit de l'hôte lui‐même ou résultant de son métabolisme ont été testées. Les odeurs de gousses ou de graines sèches de Vigna unguiculata Walp (plante‐hôte du phytophage) influencent le comportement locomoteur des femelles. Par contre, les odeurs de plantes au stade végétatif n'ont pas d'effet. Les kairomones émanant de larves, nymphes ou fèces de larves de B. atrolineatus exercent un effect attractif sur les femelles parasitoïdes. Les odeurs émanant d'adultes mâles ou femelles de B. atrolineatus ainsi que la phéromone sexuelle émise par les femelles ne sont pas attractives pour les femelles de E. vuilleti. Cette phéromone sexuelle, par contre, stimule l'activité locomotrice des parasitoïdes. La signification adaptative de ces différents stimuli olfactifs est discutée.
The effects of climate, host plant phenology and host fidelity on the genetics of apple and hawthorn infesting races of Rhagoletis pomonella
Authors: Feder Jeffrey L. , Hunt Timothy A. , Bush L. 
Published: April 2011

AbstractTrue fruit flies belonging to the Rhagoletis pomonella (Walsh) sibling species complex have been proposed to speciate sympatrically by shifting and adapting to new host plants. Here, we report the results from a series of ecological and genetic experiments conducted at a study site near Grant, Michigan, U.S.A., aimed at clarifying the relationship between host specialization and reproductive isolation for these flies. Our findings indicate that apple (Malus pumila) and hawthorn (Crataegus mollis) infesting populations of R. pomonella are partially allochronically isolated. Differences in the timing of adult eclosion account for part of the allochronic divergence, as apple adults emerge approximately ten days earlier than hawthorn flies in the field. Genetic analyses across different life history stages of the fly show that adults do not randomly move between apple and hawthorn trees, but trend to attack the same species of plant that they infested as larvae. Estimates of interhost migration from the allozyme data suggest that from 2.8 to 10% of the apple population is of hawthorn origin and that over 20% of the hawthorn population is of apple origin. The length and quality of the growing season appear to affect the genetic composition of the host races, as allele frequencies in the hawthorn population are correlated with ambient temperature and rainfall during the spring of the preceding year. Finally, allele frequencies for six allozyme loci displaying host associated differentiation also show significant linear regressions with the timing of adult eclosion within both races. These regressions establish a link between allozyme loci displaying inter‐host differentiation and a developmental trait (adult eclosion) responsible for partially isolating the races. The slopes of the regressions are paradoxical, however, as they suggest that apple adults should eclose later, not earlier, than hawthorn flies. We conclude by discussing potential resolutions to the eclosion time paradox.
Xylem transport interruption by Anasa tristis feeding causes Cucurbita pepo to wilt
Authors: Neal J. J. 
Published: April 2011

AbstractThe plant tissues ingested by Anasa tristis (DeGeer) (Heteroptera: Coreidae) and the wilting of Cucurbita pepo L. (Cucurbitaceae) caused by A. tristis were investigated by feeding and light microscopy studies. Anasa tristis ingests both cell contents and xylem. Wilting of leaves and young plants by A. tristis is due to the interruption of all xylem transport to the plant apical to the feeding site. Xylem transport is interrupted by blockage of xylem vessels with salivary secretions or severing of xylem vessels by A. tristis stylets. Restricting feeding sites by caging demonstrates that squash bug does not produce a toxin that is responsible for wilting.
Factors influencing the acaricidal activity of flucycloxuron
Authors: Grosscurt A. C. 
Published: April 2011

AbstractContact activities of flucycloxuron on immature stages of the two‐spotted spider mite (Tetranychus urticae (Koch)) and the European red mite (Panonychus ulmi (Koch)) gradually decrease in the successive developmental stages. The levels of contact activity of flucycloxuron on larvae and protonymphs of T. urticae and P. ulmi are of the same order. Deutonymphs of T. urticae are less susceptible to contact activity than the similar stage of P. ulmi. In adult T. urticae, the transovarial ovicidal activity was used as an indicator for cuticular penetration. More than 90% of the maximal penetration into adult mites occurs within 8 h. Reversibility of the transovarial activity was not observed after 24 h, but did occur after a subsequent 48 h stay on untreated leaves.The ovo‐larvicidal activity of flucycloxuron on P. ulmi after treatment of apple leaves is strongly negatively influenced by leaf age, partly by lower retention of the spray liquid on the leaves. Leaf penetration was measured by application of flucycloxuron on leaf uppersides and assessment of the transovarial activity in mites (P. ulmi or T. urticae) infested on the undersides, one day after treatment. In this test system, leaf penetration was found to be strongly species dependent. Penetration was high in cucumber, moderate in French beans, cotton, roses and strawberry, but low in apple and pepper. Leaf penetration in French bean plants is drastically reduced at increasing leaf age. The overall positive effect of increase in relative air humidity on leaf penetration, is statistically highly significant (P = 0.001) for French beans and almost significant (P = 0.08) for cucumbers. With T. urticae on French bean it was found that in this test flucycloxuron needs more than one day for maximal leaf penetration.Although in apple leaves penetration from uppersides was low, penetration from undersides was much higher. The surfactants Arkopal N130, Silwet L‐77 and X2‐5309 enhance penetration from leaf undersides.
Biotype‐specific expression of dsRNA in the sweetpotato whitefly
Authors: Jimenez Desmond R. , Shapiro Jeffrey P. , Yokomi Raymond K. 
Published: April 2011

AbstractThis study was conducted to evaluate the effect of two different biotypes of the sweetpotato whitefly, Bemisia tabaci (Gennadius), on the induction of squash silverleaf (SSL), and to determine if double‐stranded RNA (dsRNA) occurs in geographically remote populations of the two biotypes. Recently collected B‐biotype whiteflies from Florida, Arizona, Mississippi, and Texas (SPW‐B) all contained a 7.0 kb dsRNA molecule. Kb dsRNA molecule. Laboratory colonies of A‐biotype whiteflies that were originally collected in 1981 from cotton in Arizona and California did not contain the 7.0 Kb dsRNA. When the two biotypes were compared only the SPW‐B induced rapid onset, grade 5, SSL. DsRNA similar to that found in adult SPW‐B was concentrated in whitefly nymphs, but host plant leaf tissue did not contain any consistent dsRNA molecules. SPW‐A only induced low‐grade SSL and progeny of SPW‐A that were fed on pumpkin plants displaying SSL did not acquire the ability to express dsRNA or induce SSL. Our data suggest that dsRNA is not directly involved in the induction of SSL and that SSL is a host‐specific response to a feeding injury induced by B‐biotype whiteflies. The origin and source of the 7.0 Kb dsRNA molecule remains enigmatic but its expression is constant in the whitefly biotype that is responsible for the induction of SSL and several other plant disorders in the U.S.
The use of visual cues in host evaluation by aphidiid wasps: I. Comparison between three Aphidius parasitoids of the pea aphid
Authors: Michaud J. P. , Mackauer M. 
Published: April 2011

AbstractHost evaluation behaviour was examined in three species of aphid parasitoids, Aphidius ervi Haliday, A. pisivorus Smith, and A. smithi Sharma & Subba Rao (Hymenoptera: Aphidiidae). Parasitoids were provided under laboratory conditions with three kinds of hosts representing two aphid species: (green) pea aphid, Acyrthosiphon pisum (Harris), and green and pink colour morphs of the alfalfa aphid, Macrosiphum creelii Davis. Females of all three Aphidius species distinguished between aphids on the basis of colour, movement, and host species. Patterns of host acceptance by parasitoids were species‐specific. In A. ervi, host preference was the same in light and dark conditions: pea aphid > green alfalfa aphid „ pink alfalfa aphid. In contrast, A. pisivorus attacked and accepted pea aphid and green alfalfa aphid equally in the light and preferred both of these over pink alfalfa aphid; however, it made no distinction between pea aphid and pink alfalfa aphid in the dark. Females of A. smithi attacked all three kinds of hosts (pea aphid > green alfalfa aphid „ pink alfalfa aphid) but apparently laid eggs only in pea aphid. The frequencies of attack and oviposition by all wasps were higher on ‘normal’ pea aphids than on those anaesthetized with CO2. Host recognition is confirmed by chemical cues in the aphid cuticle that are detected during antennation, and host acceptance is dependent on an assessment of host quality during ovipositor probing.
Selection of insect parasitic nematodes for biological control of the garden chafer, Phyllopertha horticola
Authors: Smits P. H. , Wiegers G. L. , Vlug H. J. 
Published: April 2011

AbstractLarvae of Phyllopertha horticola L. (Coleoptera: Scarabaeidae) cause increasing problems on sports fields and lawns in NW‐Europe. A biological control programme using insect parasitic nematodes is being developed. This paper contains the results of bioassays with various species and isolates of the nematode genera Heterorhabditis and Steinernema. In bioassays in small pots with moist sand, most of the nematode isolates gave 30–60% mortality against each of the three larval stages. The susceptibility of the grubs for nematode infection generally increased with larval development. H. bacteriophora, H. heliothidis, H. megidis, a Dutch Heterorhabditis isolate NLH‐E87.3 and S. glaseri 326 showed the highest mortality rates, with nearly 100% mortality of third instar grubs. The Dutch Heterorhabditis isolate NLH‐E87.3 and S. glaseri 326 were selected as candidates for further studies on their potential as biological control agents for P. horticola grubs in the field.
Reproductive behaviour of mated and virgin females of a solitary sawfly Dineura virididorsata
Authors: Walter G. H. , Ruohomäki K. , Haukioja E. , Vainio E. 
Published: April 2011

AbstractSex ratios of the arrhenotokous sawfly Dineura virididorsata Retz. (Hymenoptera: Tenthredinidae) are variable among populations in the field, but are biased in favour of females. We have concluded elsewhere that the sex ratios of this species cannot be satisfactorily explained by any general sex ratio model that is available. Here we present data on the different behavioural traits that are relevant to interpretation of the evolution of female‐biased sex ratios under local mate competition. We report on oviposition behaviour, mating behaviour and the patterns of movement of ovipositing virgin and mated females. Our results show that adult emergence is synchronous and females will mate daily with different males (in the laboratory, at least). This would decrease the relatedness of offspring should it also take place in the field. In addition, ovipositing females (mated and virgin) leave their site of release in a relatively short time and deposit few eggs relative to their capabilities, so siblings are unlikely to be clumped. The time that virgins spend in deposition of an egg is not different from that spent by mated females, so there is no differential ‘investment’ in this regard. These behavioural observations agree with our previous conclusion that the preconditions of current sex ratio theories are not met by D. virididorsata.
Behavioural and chemosensory responses of the turnip root fly (Delia floralis) to glucosinolates
Authors: Simmonds M. S. J. , Blaney W. M. , Mithen R. , Birch A. N. E. , Lewis J. 
Published: April 2011

AbstractThis study investigates the behavioural and neural mechanisms involved in the oviposition behaviour of the turnip root fly, Delia floralis (Fallen). Behavioural studies showed that glucosinolates modulated the oviposition behaviour of the flies on artificial leaves as well as the number of eggs laid in the soil at the base of these leaves. Electrophysiological responses to glucosinolates were obtained from type A and type D sensilla on the prothoracic and mesothoracic tarsi, as well as from the long contact sensilla on the labellum. The neural responses from these sensilla were positively correlated with the oviposition behaviour of the flies and with the number of eggs laid. Of the eleven glucosinolates tested in the behavioural and electrophysiological tests, the flies were most responsive to glucobrassicanapin, gluconapin and glucobrassicin. The type D tarsal sensilla were more responsive to the glucosinolates than either the type A tarsal sensilla or the labellar sensilla. The structure‐activity investigations showed that slight modifications to the chemical composition of the glucosinolates resulted in changes in neural activity.
Effects of fluvalinate on two‐spotted spider mite dispersal, fecundity and feeding
Authors: Holland J.M. , Chapman R.B. , Penman D.R. 
Published: April 2011

AbstractResidual deposits of fluvalinate caused two‐spotted spider mite, Tetranychus urticae Koch, dispersal by running off (run‐off) and spinning down (spin‐down) from treated leaves. Run‐off occured at concentrations from 0.0005 g a.i. 1−1 and reached a peak at 0.01 g a.i. 1−1. Spin‐down was more predominant at concentrations above 0.01 g a. i. 1−1. Spin‐down and run‐off proportions varied with fluvalinate formulation. Oviposition was temporarily suppressed on fluvalinate‐treated leaves, presumably because of an irritant effect which reduced feeding. An emulsifiable concentrate formulation caused the largest reductions in oviposition. Oviposition returned to the level exhibited by untreated mites two days after removal from treated surfaces. Oviposition and feeding were positively correlated and both declined reciprocally with increasing fluvalinate concentration.
Abiotic mortality factors of the coffee berry borer (Hypothenemus hampei)
Authors: Baker P. S. , Rivas A. , Balbuena R. , Ley C. , Barrera J. F. 
Published: April 2011

AbstractMortality of the coffee berry borer was studied under controlled laboratory conditions in Tapachula, Mexico. For adult female borers subjected to a range of relative humidities (RH) without food at 25°C, the longest mean survival time (20 days) was obtained at 93.5% RH. Adult borer survival was also studied at a range of temperatures for a fixed relative humidity (93.5% RH); at 20°C mean survival time was 28 days. Fecundity and mortality of borer stages in berries was studied for a range of humidities at 25°C. Maximum fecundity was obtained at 90 and 93.5% RH. Immature stages were ejected from the berry at 84% RH and above, which is interpreted as a form of brood hygiene.
The effect of elevated UV‐B radiation on herbivory of pea by Autographa gamma
Authors: Hatcher Paul E. , Paul Nigel D. 
Published: April 2011

AbstractLeaves exposed to above‐ambient fluxes of ultraviolet‐B (UV‐B) radiation commonly contain increased concentrations of phenolic compounds which may influence herbivores. However, the hypothesis that elevated UV‐B modifies herbivory, whether mediated by phenolics or other plant constituents, has rarely been studied experimentally. We investigated the responses of the moth Autographa gamma L. (Lepidoptera: Noctuidae) to pea (Pisum sativum L.) grown at a range of plant‐effective UV‐B fluxes. Although total phenolics did increase significantly with increasing UV‐B, this change had little deleterious effect on the 5th instar larvae of A. gamma. However, tissue nitrogen also increased with increasing UV‐B. Increased nitrogen was correlated with an increase in the efficiency with which larvae utilized their food and in larval growth rate, but in a reduction in the amount of plant material consumed. The apparently major role of nitrogen in determining herbivore responses to changing UV‐B demonstrates the risks in predicting such responses soley on the basis of changes in phenolics and other secondary metabolites.
Variation in phenology and nutritional quality between host plants and its effect on larval performance in a specialist butterfly, Zerynthia rumina
Authors: Jordano Diego , Gomariz Ginés 
Published: April 2011

AbstractThe main host plants of the butterfly Zerynthia 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, while A. 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 of A. baetica, and most of these leaves are produced well before the larvae hatch. In laboratory experiments, caterpillars feeding on either new or mature A. longa leaves grew faster and converted food into biomass more efficiently than those feeding on new A. baetica leaves. These differences are related to variation in nutritional quality among the host plants. Estimates of butterfly abundance were lower in sites where Z. rumina uses A. baetica, compared with those where the host is A. longa. The potential differential effect of these two food plants on the densities of local butterfly populations relying on them is discussed here.
An in vitro rearing system for the propagation of the ectoparasitoid Catolaccus grandis
Authors: Guerra Antonio A. , Martinez Susana 
Published: April 2011

AbstractAn experimental ‘closed’ rearing system, where egg and larval manipulations were eliminated, was developed for the in vitro rearing of Catolaccus grandis (Hymenoptera: Pteromalidae) Burks, an important ectoparasitoid of the cotton boll weevil, Anthonomus grandis Boheman. In this rearing model, n‐hexane (a synthetic ovipositional stimulant for this parasitoid), was smeared on the Parafilm® cover of a modified rearing chamber (a Multiwell®) tissue culture plate) to induce the deposition of uncontaminated eggs, on the inner side of this waxy membrane, and on or around an agar retained diet that had been dispensed into the individual chamber wells. When the efficiency of the in vitro rearing system was compared to the current in vivo rearing method for this species, the duration of the life cycle was significantly shorter in parasitoids reared in vivo, but this difference was less than one day (17.8 vs 17.1 days, respectively). On the other hand, the number of eggs laid in the in vitro rearing chamber during a 4 h period was c. 2.5 times greater than in the conventional in vivo rearing apparatus, and adult yields were c. 25% greater when using the in vitro closed rearing method. Male to female ratios were c. 1:9 when reared in vitro as compared to 1.0:1.5 for those reared in vivo. There were no apparent adverse effects of this in vitro rearing system on the parasitoid's general behavior and reproduction after two consecutive generations.