bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host race formation in the gall wasp Andricus mukaigawae
Authors: Abe Yoshihisa 
Published: April 2011

AbstractAllochronic isolation between the two host races of the bisexual generation of A. mukaigawae (Mukaigawa) (Hymenoptera: Cynipidae) was demonstrated in the field. Assortative mating seems to occur in the bisexual generation of each race. Genetic changes of ovipositional preference probably played an important role in the host race formation; it is likely that little or no genetic change in survival was required in this process. A difference in host phenology seems to have caused the allochronic isolation of the bisexual generation between the parent population on the original host tree species and its daughter population on the new host tree species. Gene flow between them may have been restricted ever since the initial host shift. The host race formation of this wasp probably represents an example of ‘sequential evolution’.RésuméFormation de races spécifiques des hôtes chez Andricus mukaigawaeL'isolement allochronique de 2 ‘races’ spécifiques aux hôtes différents a été prouvé dans la nature pour la génération bisexuée de A. mulaigawae (Hymen., Cynip.). Des accouplements assortis semblent exister à l'intérieur de la génération bisexuée de chaque ‘race’. Des différences génétiques dans le choix du lieu de ponte doivent jouer un rôle important dans la formation de ces ‘races’; il n'est probablement pas nécessaire qu'il y ait des changements génétiques dans la survie, pour obtenir cette genèse. Une différence dans la phénologie des hôtes semble avoir entrainé l'isolement allochronique dans la génération bisexuée entre les populations parentales suivant l'espèce originelle d'arbre hôte, et dans ses populations filles suivant les nouvelles espèces d'arbres hôtes. Le flux génique entre ces populations peut avoir été limité depuis le changement initial d'hôtes. Chez ce cynipide la formation de ‘races’, en fonction de l'hôte, représente probablement un exemple ‘d'évolution séquentielle’.
Cold hardiness of larvae of the southwestern corn borer, Diatraea grandiosella
Authors: Popham H. J.R. , George M. F. , Chippendale G. M. 
Published: April 2011

AbstractThe cold‐hardening capacity of field‐collected larvae from southeast Missouri and laboratory‐reared larvae of the southwestern corn borer, Diatraea grandiosella Dyar, was examined. Supercooling points of non‐diapause and diapause larvae collected from maize plants grown in Missouri (36° 30′ N lat.) were ca. –7.0 °C. The hemolymph melting points of diapause field larvae (–0.8 °C) were significantly lower than those of non‐diapause larvae collected in July (–0.5 °C). The supercooling points of hemolymph from non‐diapause and diapause field larvae ranged randomly from –10° to –18 °C. Supercooling points of non‐diapause laboratory larvae increased from –13° to –10 °C prior to pupation, whereas those of diapause larvae increased similarly before the onset of diapause, but then decreased during diapause to ca. –17 °C. No change in supercooling points or capacity to survive in the presence of ice was observed in diapause laboratory larvae acclimated at 4 °C for 63 days. Laboratory and field larvae began to freeze at ca. –1.5 °C in the presence of ice, but survived to several degrees below their melting points. The high supercooling points of field larvae appeared to be due to the presence of an environmental ice‐nucleator. Although data for laboratory larvae indicate sufficiently low supercooling points to permit winter survival in southeastern Missouri, considerable larval mortality occurs in the field due to inoculative freezing and the presence of an ice‐nucleator.
Infection sites of the entomopathogenic fungus Beauveria bassiana in the larvae of the mosquito Aedes aegypti
Authors: Miranpuri G. S. , Khachatourians G. G. 
Published: April 2011

AbstractA series of experiments were conducted to determine the infection sites of the entomopathogenic fungus Beauveria bassiana after ingestion by the larvae of Aedes aegypti. The timing of the host death in relation to larval molting, the principle sites of fungal infection and development in host tissues were studied. Fungal conidiospores (CS) and blastospores (BS) were used separately for treatment of mosquito larvae. Although in most instances CS germinated and developed within the host, in others there was a premature abortion of the fungal development cycle. On the other hand, BS ingested by the larvae showed differences in the fungal development stages in the larval tissues. While the two primary infection sites were the head and the anal region, the most preferred site for fungal development was the larval gut. No more than two cycles of fungal development can occur in the host. Although both CS and BS are effective as larvicides, BS is far more pathogenic.RésuméEmplacement d'infection des larves des moustiques Aedes aegypti avec des champignons Beauveria bassianaUne série d'expériences a été menée afin de déterminer les emplacements d'infection du fongus entomopathogénique Beauveria bassiana (souche GK 2016) lequel avait été ingesté des larves d’ Aedes aegypti. On a étudié le moment de la mort des hôtes en relation des mues des larves, les emplacements principaux où se conduit l'infection fongale et le développement du fongus dans des tissus divers d'hôte. On a utilisé les conidiospores (CS) et les blastospores (BS) séparément pour traitement des larves des moustiques. Bien que dans la plupart des cas CS ait germiné et se soit développé chez l'hôte, en d'autres cas, CS a germiné mais n'avait pas produit du BS évidemment grâce à l'avortement prématuré du cycle de développement des fongus chez l'hôte. Le BS qui avait été ingesté dans les larves présentait des stages différents de développement du fongus dans les tissus des larves. Quoique les deux emplacements principaux étaient la tête et la région anale, l'emplacement préféré pour le développement du fongus était l'intestin des larves. Nous montrons qu'il n'y a plus de deux cycles de développement du fongus chez l'hôte. Bien que CS et BS soient efficaces comme larvicides, BS est de loin plus pathogène.
How does Drosophila melanogaster overwinter?
Authors: Izquierdo J. I. 
Published: April 2011

AbstractIn temperate regions low temperatures seem to be the most restrictive factor for survival of Drosophila natural populations, which depends on the capacity of one or more developmental stages to resist unfavourable winter conditions. In this study we have attempted to answer the question of how D. melanogaster overwinters under natural temperature conditions. Only adults overwintered and no diapause was observed in any developmental stage. Thus, developmental duration becomes a decisive component with respect to overwintering potential and, therefore, the preadult stages are unlikely to overwinter. Possible evolutionary steps in adaptation to cold regions are discussed.
Inhibition of Telenomus sphingis an egg parasitoid of Manduca spp. by trichome/2‐tridecanone‐based host plant resistance in tomato
Authors: Farrar R. R. , Kennedy G. 
Published: April 2011

AbstractThe resistance of accession PI 134417 of the wild tomato Lycopersicon hirsutum f. glabratum C. H. Mull to Manduca sexta (L.) (Lepidoptera: Spingidae) and Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) is conditioned by the high densities of 2‐tridecanone‐containing, glandular trichomes associated with the foliage. In laboratory experiments, rates of parasitism of M. sexta eggs by Telenomus sphingis (Ashmead) (Hymenoptera: Scelionidae) were lower among eggs on PI 134417 foliage than among eggs on foliage of the cultivated tomato L. esculentum Mill. (cv. Better Boy). The latter is characterized by a significantly lower density of type VI glandular trichomes than PI 134417 and an absence of 2‐tridecanone. Parasitism by T. sphingis was also reduced among eggs on foliage of the F1 hybrid between PI 134417 and L. esculentum. The hybrid foliage lacks 2‐tridecanone but has a density of type VI glandular trichomes that is intermediate between those of PI 134417 and L. esculentum, indicating that elevated densities of type VI glandular trichomes adversely affect T. sphingis. This conclusion was further substantiated by the finding that there were no differences among plant lines in the levels of parasitism of M. sexta eggs when the eggs were on foliage that had been divested of glandular trichomes.In bioassays in which T. sphingis adults or immatures in host eggs were exposed to filter paper treated with 2‐tridecanone at rates comparable to those associated with PI 134417 foliage, 2‐tridecanone was acutely toxic and caused high levels of mortality. In addition, at high concentrations, 2‐tridecanone vapors were repellent to T. sphingis adults. However, when exposed to PI 134417 foliage, few T. sphingis adults were killed.Parasitism of M. sexta eggs was unaffected when the eggs were deposited by moths reared as fifth instar larvae on diet containing 2‐tridecanone and/or 2‐undecanone at levels comparable to those associated with PI 134417 foliage.
The influence of phenolic compounds on the suitability of three Salix species as hosts for the willow beetle Phratora vulgatissima
Authors: Kelly M. T. , Curry J. P. 
Published: April 2011

AbstractThe phenolic glycosides salicin and salicortin were found to influence larval growth and development rates and adult feeding preference of Phratora vulgatissima in laboratory feeding studies. Salicortin was more toxic to larvae than salicin, and none of the third instar larvae fed on Salix viminalis leaves amended with 1.52% (fresh mass) salicortin pupated. Condensed tannins (proanthocyanadins) did not affect larval performance. It was concluded that Salix burjatica resistance to willow beetle is due to the high levels of salicortin which occur in leaves of this species.
Factors affecting calculation of nutritional induces for foliage‐fed insects: an experimental approach
Authors: Bowers M. Deane , Stamp Nancy E. , Fajer Eric D. 
Published: April 2011

AbstractTo determine how nutritional indices for insects fed leaves are affected by the experimental conditions and the physiology of the plant material, we used larvae of the buckmoth, Hemileuca lucina Hy. Ed. (Saturniidae) and their hostplant Spiraea latifolia Ait. Bork (Rosaceae). Under experimental conditions identical to those used to determine larval nutritional indices, we found that the age of leaves (new versus mature) significantly affected their metabolism and water loss, but simulated herbivory did not directly affect leaf metabolism. Over a 6‐day test, nitrogen concentration showed an initial increase followed by a gradual decline, and was higher in new leaves compared to mature leaves. New leaves increased in protein concentration and then gradually returned to the initial level, whereas mature leaves changed little over the 6‐day test. These changes in percent nitrogen and protein may largely reflect the disproportional changes in non‐nitrogenous materials. Solitary and grouped larvae had similar growth rates on new leaves, but they differed on mature leaves. Deliberate manipulation of larvae during the course of an experiment significantly reduced relative growth rates by increasing duration of the stadium rather than by decreasing biomass gained. Two methods of estimating larval gut contents at mid‐stadium were compared: weight of frass produced and weight of digestive tract and contents. After the end of the 4‐day test period used to determine nutritional indices, the digestive tracts with food accounted for 10.8% of the larval dry weight. Larval frass produced in 24 h after the end of the test period comprised 9.3% of the larval dry weight. Correction factors for plant metabolism changed nutritional indices by 1 to 8%, while those for larval gut contents altered indices by 2 to 15%.
Field response of the pine sawfly Neodiprion sertifer to the pheromone (2S, 3S, 7S)‐diprionyl acetate and its stereoisomers
Authors: Anderbrant O. , Löfqvist J. , Högberg H.‐E. , Hedenström E. , Wassgren A.‐B. , Bergström G. , Bengtsson M. , Magnusson G. 
Published: April 2011

AbstractAll eight optical isomers of 3,7‐dimethyl‐2‐pentadecanyl acetate (diprionyl acetate), of high optical purity (>97.4%), were tested for a behavioural activity on male pine sawflies, Neodiprion sertifer (Geoffr.) (Hymenoptera: Diprionidae), in northern Europe. Males were strongly attracted to (2S, 3S, 7S)‐diprionyl acetate. Addition of more than 0.1% of the (2S, 3R, 7R)‐isomer reduced the catch and above 2% the attraction was completely inhibited. Contrary to what has been reported for North American and Japanese populations, so significant synergistic effect of small amounts of the (2S, 3R, 7R)‐isomer could be demonstrated. The effects of addition of the other six optical isomers alone or in combinations, were also studied, but none was found to be a synergist. The (2S, 3R, 7S)‐isomer had a weak inhibitory effect, and completely inhibited the attraction to the (2S, 3S, 7S)‐isomer when applied in about equal amounts as the attractant. In some cases a reduction in catch was noted when other isomers were tested, but this could be attributed to the very small amounts of the inhibitory (2S, 3R, 7R)‐isomer present in these isomers.
Mating behaviour of the corn stalk borer Sesamia nonagrioides
Authors: Babilis N. A. , Mazomenos B. E. 
Published: April 2011

AbstractThe mating behaviour of the corn stalk borer Sesamia nonagrioides (Lef.) [Lepidoptera: Noctuidae] was studied under laboratory conditions at 25 ± 1 ° C, 65 ± 5 % r.h. and 16:8 (L:D) regime. The females began calling during the first scotophase following emergence, the peak of calling occurred during the second scotophase and thereafter decreased. Maximum calling was observed between the fourth and sixth hour of the scotophase. The calling pattern varied with age. During the first and second scotophase most of the females were calling continuously, while during the third and fourth scotophase periodic calling was observed. The mean onset of calling was advanced and the mean length of calling per day was increased slightly as the female became older. Females held for 72 h in continuous darkness exhibited an endogenous circadian rhythm of calling. Matings began during the first scotophase following emergence and the peak of mating was observed during the second scotophase. Mated females did not remate. Few males mated more than once during the following scotophases.
The role of temperature, photoperiod, crowding and plant quality on the production of alate viviparous females of the bird cherry‐oat aphid, Rhopalosiphum padi
Authors: De Barro P. J. 
Published: April 2011

AbstractExperiments indicated that for offspring of apterous Rhopalosiphum padi (L.) (Hemiptera: Aphididae), photoperiod and crowding were the most important determinants of wing development whereas crowding and plant quality were more significant for the next generation. Plant quality became increasingly important as temperature increased while crowding became less so. More alates developed on plants previously infested with aphids, indicating that aphid feeding reduced plant quality. High temperature suppressed alatoid production, but could be overcome by crowding. Temperature appeared to influence wing development indirectly rather than directly by acting on the aphid through the plant. Adult weight and potential fecundity were also reduced for aphids which fed on previously infested plants.
Variability in the transmission efficiency of potyviruses by different clones of Aphis gossypii
Authors: Lupoli R. , Labonne G. , Yvon M. 
Published: April 2011

AbstractA sample of seventy‐two Aphis gossypii Glover (Homoptera: Aphididae) clones was collected in southeastern France. The efficiency of these clones to transmit a potyvirus (papaya ringspot virus T‐strain) was assessed in controlled conditions. In a first screening, the virus was transmitted by all clones and a 3.5‐fold difference between the most and least efficient clones was obtained. During subsequent trials, which were carried out to confirm the differences in the transmission efficiency of these clones, only one clone proved to be more efficient than the others. This difference appeared consistent over a 1‐year period, and was also confirmed with 4 other related potyviruses.RésuméUn échantillon de 72 clones de A. gossypii a été collecté dans le Sud‐Est de la France. L'efficacité de transmission d'un potyvirus (PRSV‐T) a été mesurée en conditions contrôlées pour chacun de ces clones. Un premier screening a permis de montrer que tous les clones transmettaient ce virus, et qu'un rapport de 3,5 existait entre l'efficacité de transmission du clone le plus efficace et celle du clone le moins efficace. Au cours des essais ultérieurs destinés à confirmer ces différences, un seul clone s'est montré significativement plus efficace que les autres. Cette différence s'est maintenue pendant la période d'essais (1 an). Elle s'est reproduite avec 4 autre potyvirus apparentés.
On the function of pea flower feeding by Bruchus pisorum
Authors: Clement S. L. 
Published: April 2011

AbstractPea flower feeding by adult pea weevils, Bruchus pisorum (L.) (Coleoptera: Bruchidae), with special emphasis on nectar feeding, was investigated in a series of laboratory experiments. Male and female adults robbed nectar from flowers of the garden and field pea, Pisum sativum L., and females which fed on the nectar, petals, and female organs of pea flowers lived significantly longer than those denied food and water and those that fed on water only. The results of other experiments suggested that pea flower qualities other than pollen influenced the reproductive success of female B. pisorum. It is hypothesized that pollen seeking B. pisorum effected cross‐pollination in the wild progenitor of the modern‐day autogamous pea, and adult pea weevils of both sexes rob pea nectar to obtain a readily available source of energy to sustain flight.
Interaction entre la cochenille du manioc Phenacoccus manihoti et ses différentes plantes‐hôtes: étude de la teneur de la sève en acide aminé et en sucre
Authors: Tertuliano M. , Le Rü B. 
Published: April 2011

RésuméL'analyse (acides aminés et sucres) d'extrait de feuille, de 5 variétés de manioc (Manihot esculenta), du Faux caoutchouc (Hybride de M. esculenta × M. glaziovii), du Poinsettia (Euphorbia pulcherrina) et du Talinum (Talinum triangularae), caractérisés par différents degrés de résistance par antibiose à la cochenille du manioc (Phenacoccus manihoti (Mat. Ferr.)) (Homoptera: Pseudococcidae), a été réalisée sur des extraits obtenus par centrifugation du matériel foliaire. Les teneurs en acides aminés, très différentes d'une plante à l'autre, apparaissent aussi importantes entre les variétés de l'espèce manioc qu'entre les différentes espèces végétales avec respectivement un rapport de variation de 4, 5 et 5, 5. De měme, les teneurs en sucres (exprimées en équivalent saccharose), sont très différentes d'une plante à l'autre avec un rapport de variation de 1 à 33 entre les deux extrěmes, si l'on ne considère que l'espèce M. esculenta, il n'est plus que de 3, 5.Des différences dans les proportions relatives des acides aminés libres d'extrait de feuille sont observées aussi bien entre les variétés de manioc qu'entre les espèces végétales. Cependant pour toutes les plantes étudiées l'acide glutamique, la glutamine, l'ethanolamine, et l'alanine représentent près de 50% des acides aminés de l'extrait de feuille; l'acide aspartique, l'asparagine et la sérine près de 20% tandis que la tyrosine, la méthionine, l'isoleucine, la leucine et la lysine sont présents en très faibles pourcentages.Le degré de résistance à la cochenille du manioc des différentes plantes‐hôtes n'a pu ětre relié, ni à la teneur de leur extrait de feuille en acides aminés et en sucres, ni à leur composition relative en acides aminés. Il n'a pu ětre non plus relié au rapport Sucres/Acides amineés. Nos résultats suggèrent que des caractéristiques biochimiques autres que celles étudiées dans ce travail interviennent dans les mécanismes de résistance vis‐à‐vis de la cochenille du manioc.
Comparison of learning in related generalist and specialist eucoilid parasitoids
Authors: Simons M. T. T. Poolman , Suverkropp B. P. , Vet L. E. M. , de Moed G. 
Published: April 2011

AbstractEffects of learning in two microhabitat specialists, Leptopilina boulardi Barbotin et al. and L. fimbriata Kieffer were compared to previous and new results of learning in the microhabitat generalist L. heterotoma Thomson. Females were given one or more oviposition experiences on hosts in different types of substrate. In all species oviposition experience affected the choice for a substrate, although this effect of learning was considerably less in L. fimbriata compared to the other two species. Patch times, known to be highly determined by experience in the generalist L. heterotoma, were much less flexible in the specialists. L. boulardi and L. fimbriata have fixed patch times on their natural substrate and have variable patch times on other substrates only. In all three species one oviposition affected the choice for a substrate. Additional ovipositions showed no different effect. An accumulative effect of the number of ovipositions on patch times was found in L. heterotoma only. Retention of the learning effect was only studied in L. boulardi, and was shown to be similar to that reported for L. heterotoma, i.e. two to three days. Although learning was found in both the generalist and the specialist species studied, it seems to affect their foraging behaviour differently.
Toxicity of the limonoid allelochemical cedrelone to noctuid larvae
Authors: Koul O. , Isman M. B. 
Published: April 2011

AbstractThe limonoid cedrelone, a constituent of Cedrela toona and C. odorata (Meliaceae) was evaluated as a larval growth inhibitor for the polyphagous noctuids Peridroma saucia and Mamestra configurata by examining its effects on development and feeding behaviour. Cedrelone significantly inhibited growth of different larval instars when administered orally (in artificial diet), topically or via injection. Nutritional analyses revealed that both growth inhibition and reduced consumption are a consequence of post‐ingestive malaise rather than a peripherally‐mediated antifeedant effect. Cedrelone administered via injection to sixth instar P. saucia larvae also inhibited growth, delayed development, and resulted in considerable larval mortality. However, all larvae which survived treatment pupated successfully. The present study suggests that the toxicity of cedrelone does not likely involve the endocrine system.
Intraspecific variation in bionomic characters of the Mexican bean weevil, Zabrotes subfasciatus
Authors: Credland P. F. , Dendy J. 
Published: April 2011

AbstractZabrotes subfasciatus (Boheman) (Coleoptera: Bruchidae) is native to parts of Central and South America but has now been spread to many others areas. It commonly infests the seeds of both Lima beans, Phaseolus lunatus, and common beans, Phaseolus vulgaris. Five geographic populations were found to differ in fecundity, patterns of egg distribution, times of development and adult sizes when they were kept under the same conditions. Each population also differed unpredictably from the others in its response to different cultivars of host seed. These differences have been shown to be of considerable importance in determining the potential pest status of the populations and should also promote caution in making predictions about the responses of different populations to new cultivars of bean for agricultural use.