bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trade‐offs in responses to host plants within a population of a generalist herbivore, Choristoneura rosaceana
Authors: Carrière Yves , Roitberg B. D. 
Published: April 2011

AbstractEvolutionary constraints on the ability of herbivores to efficiently use a set of phytochemically similar hosts, while maintaining a high performance on phytochemically different hosts, are central in explaining the predominance of host specialization in phytophagous insects. Such feeding trade‐offs could be manifested within insect populations as negative genetic correlations in fitness on different host species. We tested the hypothesis that feeding trade‐offs were present within a population of the obliquebanded leafroller, Choristoneura rosaceana (Harris). Components of fitness were measured in families originating from an apple orchard that were fed on four host‐plant species in the laboratory. Under the conditions of this experiment, all across‐host genetic correlations were strongly positive, suggesting that this population comprised true generalists. With the exception of diapausing propensity, the heritability of the fitness components tended to be lower in caterpillars fed on apple leaves than in insects fed other hosts. This suggests a constraint on the selective response of the fitness components in the orchard environment.
Population dynamics of the potato tuber moth on processing tomatoes in Israel
Authors: Gilboa Smadar , Podoler Haggai 
Published: April 2011

AbstractThe potato tuber moth (PTM), Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), is a major pest of processing tomatoes, Lycopersicon esculentum Mill. (Solanaceae), in Israel. The larvae penetrate the tomato fruit through the stem end and present a serious threat to crop quality. Foliage and fruit samples were taken in nine commercial tomato fields located in Israel's three main tomato growing areas, two of which are potato growing areas as well. PTM was not found where potatoes were absent. Potato harvest in nearby fields was found to be the most significant factor affecting seasonal trends in PTM population density in tomatoes. All four larval instars were found in foliage on all sampling dates. Significantly higher proportions of first instars were found during the population density increase which followed potato harvest. Damaged fruits did not contain first instar larvae, indicating that PTM never undergoes complete development within tomato fruit. Fruit damage levels at harvest were positively correlated to the peak mean population densities on foliage and the date they were observed. In tomato fields not adjacent to potatoes, infestation was first observed at the edge of the field. Both before and after the potato harvest in nearby fields, population density at the edge of the field was significantly higher than at the center. In tomato fields adjacent to potatoes, no significant differences were found between population densities at the edge and center before the potatoes were harvested. After the potato harvest, population density at the center of tomato fields was higher than at the edge.
Potentialités prédatrices de Forficula auricularia sur le psylle du poirier Cacopsylla pyri
Authors: Lenfant C. , Lyoussoufi A. , Chen X. , d'Arcier F. Faivre , Sauphanor B. 
Published: April 2011

RésuméReconnu comme agent régulateur des populations aphidiennes de diverses cultures, Forficula auricularia L. est également décrit comme potentiellement actif sur les Homoptéres Psyllidae. Nous avons évalué en conditions de laboratoire puis semi‐contrôlées en verger les composantes numériques et spatiales de la prédation de F. auricularia sur le psylle du poirier, Cacopsylla pyri (L.). Pour de faibles densités de proies, le poids consommé par une larve du 3ème stade est équivalent sur oeufs de psylles et sur une proie alternative constituée d'oeufs d'Ephestia kuehniella Zeller. Le maximum journalier s'établit à 10 mg pour ce stade larvaire, soit plus d'un millier d'oeufs de psylles. Les tests révèlent une réponse de type densité ‐ dépendant, aboutissant à une forte réduction de la taille des agrégats de la proie. La prédation des larves de 3ème et 4ème stade de F. auricularia s'exerce sur tous les stades préimaginaux de C. pyri. La colonisation au printemps de la strate arborée par les larves du 3 ème stade quittant le terrier maternel coîncide avec les pontes de 2ème génération de psylles, phase de multiplication la plus intense de ce ravageur. Les effectifs en vergers de ce prédateur polyphage et univoltin sont souvent élevés et peu dépendants de ceux de la proie. Compte tenu de sa capacité prédatrice sur le psylle, il paraît justifié de raisonner les interventions chimiques de manière à préserver ses populations en vergers de poiriers.SummaryPotential of Forficula auricularia L. as predator of pear psylla Cacopsylla pyri (L.).Forficula auricularia L. is a well known aphid predator, and is also described as potentially active on Psyllidae. We studied the numeric and spatial components of the predation of F. auricularia on pear psylla, Cacopsylla pyri (L.) under laboratory and semifield conditions. At low prey density, a young third‐instar larvae consumed as many psylla eggs as Ephestia kueheniella Zeller eggs, offered as alternative prey. The functional response to prey density revealed a maximum daily consumption of 10 mg per larvae, i.e. more than 1000 psylla eggs. The tests revealed a density‐dependent response, which strongly reduced the size of large prey groups. Third and fourth instar earwigs consumed all preimaginal psylla instars. In the spring, colonisation of pear trees by the third instar earwigs coincides with the egg‐laying of the 2nd generation of C. pyri. The natural populations in orchards of this univoltine and polyphagous predator are little dependent of the prey population. Because of F. auricularia high predatory capacity, its destruction by chemicals should be avoided in pear tree orchards.
The influence of glucosinolates and sugars on feeding by the cabbage stem flea beetle, Psylliodes chrysocephala
Authors: Bartlet E. , Parsons D. , Williams I. H. , Clark S. J. 
Published: April 2011

AbstractAgar was used as an artificial substrate to investigate the feeding behaviour of the cabbage stem flea beetle, Psylliodes chrysocephala L. (Coleoptera: Chrysomelidae), an important pest of winter oilseed rape (Brassica napus) in Europe. Both glucosinolates and sugars stimulated feeding when added to agar. The amount of feeding that occurred was affected by the type and concentration of glucosinolate and sugar and also by combinations of components. Although glucosinolates were potent feeding stimulants for P. chrysocephala, they were not a prerequisite for feeding, nor does it seem likely that glucosinolate profiles are used by this species to discriminate amongst cruciferous plants at the gustatory level.
Selection response of the Colorado potato beetle for adaptation to the resistant potato, Solanum berthaultii
Authors: França Félix H. , Plaisted Robert L. , Roush Richard T. , Via Sara , Tingey Ward M. 
Published: April 2011

AbstractThirty cohorts of the Colorado potato beetle (CPB) were reared for ten consecutive generations on the cultivated potato, Solanum tuberosum, and on two accessions (PI 473331 and PI 473334) of the resistant wild species, S. berthaultii. At each generation, selection was imposed for increased survival, decreased development time, and for increased fecundity. Although several parameters responded to selection, net replacement rate (R0) on S. berthaultii was consistently less than 1/3 that on cultivated potato. At the tenth generation, each S. tuberosum strain female replaced herself with 110 daughters, whereas females from strains reared on PI 473334 and PI 473331 produced an average of 30 and 7 daughters, respectively. Slopes of the R0 regression lines for populations reared on S. tuberosum and S. berthaultii did not differ from zero, indicating no significant response to selection. Our findings suggest that populations of the Colorado potato beetle may have genetic variability in some performance traits for adaptation to S. berthaultii, but that adaptation is unlikely to occur as rapidly as previously reported.
Temperature‐allelochemical interactive effects on performance of Manduca sexta caterpillars
Authors: Stamp N. E. , Temple M. P. , Traugott M. S. , Wilkens R. T. 
Published: April 2011

AbstractA series of experiments was conducted to ascertain the effects of temperature and allelochemicals on the performance of an insect herbivore, with the goal of methodically expanding the cumulative data set on interactive effects of temperature and allelochemicals. The allelochemicals examined were caffeine, chlorogenic acid, quercetin, tannic acid and tomatine with the thermal regimes 20:15 °C versus 30:15 °C. Growth, molting time and food utilization efficiencies of third instar tobacco hornworms (Manduca sexta (L.)) were measured. Our results indicated that reductions in developmental rate by the phenolics were primarily due to effects occurring around and during molt initiation, that different phenolics may affect molt processes differently, and that some of the effects of the phenolics were a function of temperature, with greater negative effects at cool temperature. Negative effects of caffeine were most pronounced earlier in the stadium rather than during molt processes and, for some variables, the effect of caffeine was also a function of temperature.
Dispersal of adult female fig wasps: 2. Movements between trees
Authors: Ware Anthony B. , Compton Stephen G. 
Published: April 2011

AbstractFig wasps (Chalcidoidea, Agaonidae, Agaoninae) are the exclusive pollinators of fig trees (Ficus spp., Moraceae). Fig development on the African fig tree, F. burtt‐davyi, is normally synchronised on individual trees, but not between trees. Consequently the females of each generation of the pollinating species (Elisabethiella baijnathi) have to disperse to other trees to find ‘receptive’ figs which are suitable for oviposition. This paper examines this aspect of fig ‐ fig wasp biology. The flight speed of insects is closely linked to their size, and directional flight is difficult for small insects, such as fig wasps, in all but the lightest of winds. We investigated the movements of fig wasps between trees using sticky traps placed around fig trees or near cotton bags containing figs. Away from the trees, the densities of flying wasps at different heights was also determined. When the wasps disperse from their natal figs they take off near‐vertically. They are unable to exert directional control once they enter the air column and are subsequently blown downwind. Near receptive host trees the wasps appear to lose height and then fly upwind at speeds of around 25 cm/sec.
Effect of photoperiod and thermoperiod on the eclosion rhythm of Trichogramma evanescens
Authors: Zaslavski V. A. , Zinovjeva K. B. , Reznik S. Ya. , Umarova T. Ya. 
Published: April 2011

AbstractThe dynamics of adult eclosion in Trichogramma evanescens Westw. were studied under (1) constant light and temperature of 20 °C, (2) photoperiods L12:D12 and L16:D8 at 20 °C, (3) thermoperiod 4 h 27 °/20 h 20 °C at constant light, (4) joint action of photo‐ and thermoperiod. The emergence was arhythmic in constant light combined with constant temperature, while a sharp monophasic rhythm was observed with the isolated action of photo‐ or thermoperiod. The ‘light‐on’ and ‘temperature step‐up’ signals were shown to act in one direction. When both signals were combined, they manifested themselves as competing entraining stimuli which, in turn, revealed an apparent individual variation in relative reactivity to the light and temperature signals. Some perspectives which follow from these observations are discussed.
Small plot mating disruption trials for tufted apple bud moth, Platynota idaeusalis, in Pennsylvania apple orchards
Authors: Felland C. M. , Hull L. A. , Barrett B. A. , Knight A. L. , Jenkins J. W. , Kirsch P. A. , Thomson D. R. 
Published: April 2011

AbstractMating disruption treatments for the tufted apple bud moth (TABM), Platynota idaeusalis (Walker), were tested in small plot trials in apple orchards in Pennsylvania. Treatments were evaluated by fruit injury and by capture of male TABM in traps baited with synthetic pheromone sources or virgin females. The TABM pheromone is a two component isomeric blend of E‐11‐tetradecen‐1‐ol (E11–14:OH) and E‐11‐tetradecenyl acetate (E11–14:Ac). A 50:50 ratio of these two components was used in standard monitoring septa and in mating disruption treatments released from either hollow fibers (‘fiber’) or PVC tubes (‘PVC’). Other pheromone blends tested included a 90:10 ratio of E11–14:Ac and E11–14:OH (‘EAc’) and its reverse (‘EOH’), mixture ‘EAc’ with 30% of the Z‐isomers (‘low EAc’), and a blend similar to the preceding with 2% Z9–12:Ac (‘generic’). These other blends were released from multi tube tape (‘tape’) or Shin‐Etsu type rope (‘rope’) dispensers. Seasonal dispenser release rate in mg ha−1 h−1 was ca. 30 for the ‘rope’ dispensers, 14 for ‘PVC’ and 6 for ‘fiber’. ‘EAc‐tape’ and ‘EOH‐tape’ were equally effective in reducing catches of males in traps baited with synthetic lures and in traps baited with virgin females. Both treatments also reduced fruit injury. ‘EAc‐rope’, ‘fiber’ and ‘PVC’ also were generally effective; whereas, the ‘low EAc’ and ‘generic’ treatments reduced trap capture less than 90% and did not reduce fruit injury. Dispenser density was positively correlated with reduction in trap capture for the ‘low EAc‐rope’ and ‘genericrope’ treatments. Traps loaded with ‘fiber’ dispensers captured more male TABM than the other treatments in non‐pheromone permeated environments. Trap capture of other tortricids was reduced in pheromone treatments. ‘EAc‐rope’ and the ‘TABM’ treatments provided mean (s.e.) percent reduction in trap catch of 99.5 (0.4) and 42.9 (10.1), respectively, for the redbanded leafroller, Argyrotaenia velutinana (Walker), and 90.4 (6.8) and 90.4 (1.3), respectively, for the obliquebanded leafroller, Choristoneura rosaceana (Harris).
Side‐effects of insecticides on two erigonid spider species
Authors: Dinter A. , Poehling H.‐M. 
Published: April 2011

AbstractThe current rearing technique for Erigone atra (Blackwall) and Oedothorax apicatus (Blackwall) (Araneae, Erigonidae) was improved. To reduce time spent rearing on live fruit flies the spiders were kept on a culture of the Collembola species Lepidocyrtus lanuginosus (Gmelin) (Entomobryidae). Side‐effects on spiders of two pyrethroid insecticides (fenvalerate and lambda‐cyhalothrin) and one carbamate insecticide (pirimicarb) were tested. Sensitivity of adults of both sexes and juveniles to insecticides and their influence on the rate of emergence of spiderlings from cocoons were investigated using topical application, spraying or residual contact. LD50 values for adults ranged from 0.49 to 2.52 ng a.i./spider for lambda‐cyhalothrin and from 5.75 to 98.20 ng a.i./spider for fenvalerate. Topical application also resulted in up to a week's delay of web‐building. A moving laboratory spraying equipment was used to spray spiders with different insecticide dosages and water volumes. Pyrethroids sprayed onto adults in webs had stronger effects than pyrethroids sprayed onto sitting or walking spiders on the soil surface. Residual contamination caused higher mortality of spiders after contact with lambda‐cyhalothrin than fenvalerate. In all tests, males were more susceptible to pyrethroids than females; this difference was related to body weight. Mortality rate was higher for E. atra than for O. apicatus. Both pyrethroids were also toxic to spiderlings. Lambda‐cyhalothrin inhibited emergence of E. atra spiderlings from cocoons. Pirimicarb was harmless to both spider species.
Cholesterol oxidase: an oöstatic and larvicidal agent active against the cotton boll weevil, Anthonomus grandis
Authors: Greenplate J. T. , Duck N. B. , Pershing J. C. , Purcell J. P. 
Published: April 2011

AbstractThe enzyme cholesterol oxidase (E.C. 1.1.3.6), purified from Streptomyces culture filtrate was previously found to have oral insecticidal activity on neonate larvae of the boll weevil (Anthonomus grandis grandis Boheman) from a laboratory population. In the present study, second instar larvae were also controlled by the enzyme at diet concentrations similar to those which control neonates (12 day LC50 = 2.4 μg.ml−1 in diet). Larvae from field‐collected adults were similarly susceptible to cholesterol oxidase in the diet. When ingested by adult females during the mating/pre‐oviposition period, cholesterol oxidase greatly reduced subsequent oviposition (83% reduction in eggs laid as compared to controls) and larval survival (97% reduction from controls). Dissection of treated adult females revealed poorly developed ovaries and few developing oöcytes. These studies were conducted to further evaluate the utility of cholesterol oxidase in a program to establish boll weevil‐resistant transgenic cotton.
The transfer of pyrethroid resistance resulting from crosses between resistant German cockroaches and susceptible Asian cockroaches
Authors: Ross Mary H. , Cochran Donald G. 
Published: April 2011

AbstractCrosses were made between the Asian cockroach, Blattella asahinai Mizukubo, and resistant strains of the German cockroach, B. germanica (L.), to assess the transfer of pyrethroid resistance to the progeny and to study the inheritance mechanism(s) involved. It was shown that the strain of Asian cockroaches studied was susceptible to four pyrethroids. F1 progeny were essentially susceptible to the same compounds. Tests with F2 progeny and those from backcrosses to the resistant parent indicated that the data for each pyrethroid fit an hypothesis of simple, autosomal, nearly completely recessive inheritance. The results are discussed from the standpoint of the impact of the Asian genome on the inheritance mechanism(s).
Assessment of Trichogramma species for biological control of forest lepidopteran defoliators
Authors: Bai B. , Çobanoĝlu S. , Smith S. M. 
Published: April 2011

AbstractIn a laboratory study, we determined the potential of three Trichogramma (Hymenoptera: Trichogrammatidae) species, T. brassicae Bezdenko, T. minutum Riley and T. nr. sibiricum Sorokina, for biological control against six species of forest lepidopteran pests, black army cutworm, hemlock looper, eastern spruce budworm, western spruce budworm, white‐marked tussock moth, and gypsy moth. Females of each parasitoid species were offered eggs from each of the six host species. Parasitization and the effect of the host species on the emerging progeny were examined and recorded. Trichogramma minutum had the broadest host range and successfully parasitized four host species out of the six offered. Trichogramma nr. sibiricum had the narrowest host range and parasitized only two species of hosts. Of the six host species, black army cutworm was the most preferred by all three Trichogramma species; white‐marked tussock moth and gypsy moth were not parasitized by any parasitoids. There was a positive correlation between the size of female offspring and their corresponding egg complement in all three parasitoid species. The developmental time of parasitoids from egg to adult was influenced by both the parasitoid and host species. Our results suggest that T. minutum has the greatest potential for biological control against various forest lepidopteran pests and that the black army cutworm may be the best target candidate for further study.
Effects of bean and wheat α‐amylase inhibitors on α‐amylase activity and growth of stored product insect pests*
Authors: Pueyo José J. , Morgan Thomas D. , Ameenuddin Nusheen , Liang Chao , Reeck Gerald R. , Chrispeels Maarten J. , Kramer Karl J. 
Published: April 2011

AbstractInsect α‐amylase inhibiting and/or growth inhibiting activities of proteinaceous inhibitors from red kidney bean (Phaseolus vulgaris) and hard red winter wheat (Triticum aestivum) were examined. The bean inhibitor was most effective in vitro against α‐amylases from the red flour beetle (Tribolium castaneum) and the confused flour beetle (T. confusum), followed by those from the rice weevil (Sitophilus oryzae) and yellow mealworm (Tenebrio molitor). The insect enzymes were from two‐ to 50‐fold more susceptible than human salivary α‐amylase. When the inhibitors were added at a 1% level to a wheat flour plus germ diet, the growth of red flour beetle larvae was slowed relative to that of the control group of larvae, with the bean inhibitor being more effective than the wheat inhibitor. Development of both the red flour beetle and flat grain beetle (Cryptolestes pusillus) was delayed by 1% bean inhibitor, but development of the sawtoothed grain beetle (Oryzaephilus surinamensis) and lesser grain borer (Rhyzopertha dominica) was not affected by either the bean or wheat inhibitor at the 1% level. Rice weevil adults fed a diet containing 1% bean or wheat inhibitor exhibited more mortality than weevils fed the control diet. When the wheat amylase inhibitor was combined with a cysteine protease inhibitor, E‐64, and fed to red flour beetle larvae, a reduction in the growth rate and an increase in the time required for adult eclosion occurred relative to larvae fed either of the inhibitors separately. The bean inhibitor was just as effective alone as when it was combined with the protease inhibitor. These results demonstrate that plant inhibitors of insect digestive enzymes act as growth inhibitors of insects and possibly as plant defense proteins, and open the way to the use of the genes of these inhibitors for genetically improving the resistance of cereals to storage pests.
Oviposition preferences and larval performance of a flower‐feeding weevil, Coelocephalapion aculeatum, in relation to host development
Authors: Heard Timothy A. 
Published: April 2011

AbstractThe oviposition behaviour of Coelocephalapion aculeatum Fall (Coleoptera: Apionidae), a host specific florivore exploiting an ephemeral resource, was studied in relation to host development. Immature inflorescences of its host, the weed Mimosa pigra L. (Mimosaceae), were categorised into 5 developmental stages ranging from first appearance to one day before opening. The duration, weight, percent abortion, and nitrogen content of each stage were measured. Oviposition preferences of C. aculeatum for all inflorescence stages were determined in multiple choice trials. Newly hatched larvae were transferred into inflorescences of each stage to determine larval survival as a function of stage. Numbers of eggs laid into inflorescences generally correlated with larval survival except that oviposition was greater in stage 4 inflorescences than expected from the larval survival. Numbers of eggs laid into inflorescences generally correlated with their carrying capacity except that adults avoided stage 5 inflorescences in which larval survival was low. The evolution of oviposition preferences of C. aculeatum appears to have been influenced by two opposing selective forces. The need to complete development before the inflorescence deteriorated would have selected for oviposition in young inflorescences. The greater availability of food and lower probability of abortion offered by older inflorescences would have selected for oviposition in these. The net outcome of these pressures has resulted in the observed oviposition strategy.