bluuebunny/crossref_metadata_2025_split huggingface dataset:
Field cage performance of two tachinid parasitoids of the tomato fruitworm on insect resistant and susceptible tomato lines
Authors: Farrar R. R. , Kennedy G. 
Published: April 2011

AbstractRates of parasitism of Helicoverpa (= Heliothis) zea (Boddie) (Lepidoptera: Noctuidae) by two tachinid parasitoid species differing in larviposition habits were measured in field cages on tomato plant lines with or without methyl‐ketone (2‐tridecanone and 2‐undecanone)‐mediated insect resistance. Hosts were placed on resistant or susceptible plants, exposed to parasitoids for 24–48 h, then held on artificial diet for parasitoid emergence. Rates of parasitism by Archytas marmoratus (Townsend) (Diptera: Tachinidae), which larviposits on its host's food plant, were significantly reduced on the resistant plants, relative to those on the susceptible plants. Parasitism by another Tachinid, Eucelatoria bryani Sabrosky, which larviposits directly into its host and does not directly contact the foliage of its hosts' food plant as a small larva, was not affected by the methyl‐ketone mediated resistance.
Adaptation of a Ceratitis capitata population Diptera, Tephritidae to an animal protein‐based diet
Authors: Zucoloto F. S. 
Published: April 2011

AbstractA population of Ceratitis capitata (Wiedemann) (Diptera, Tephritidae) reared in the laboratory on a diet based on brewer's yeast (BY) was studied in terms of adaptation to another diet based on cow's meat flour (MF). After a population fed the MF diet was established, the two populations were compared in terms of nutritional values of the diets and sexual choice. The results indicate that there was adaptation of the population to the MF diet, probably by directional selection. Assortative mating between individuals of the two populations was also observed.It is suggested that the capacity of this species to adapt to a diet based on animal protein may be maintained by the occasional practice of cannibalism during periods of competition for food.
Acid phosphatase activity in hemolymph of the migratory grasshopper, Melanoplus sanguinipes, during Beauveria bassiana infection
Authors: Vincent M. J. , Miranpuri G. S. , Khachatourians G. G. 
Published: April 2011

AbstractThe distribution and abundance of acid phosphatase (AP) in hemolymph (HL), plasma (PM) and hemocyte lysate supernatant (HLS) of the migratory grasshopper, Melanoplus sanguinipes infected with Beauveria bassiana (strain GK 2016) has been examined. AP activity was determined at intervals from 30 min to 60 h postinjection of 2 μl of 1 times 108conidia/ml per grasshopper. The enzyme was detected with the substrate β‐glycerophosphate in sodium acetate acetic acid buffer form hemocytes (HC) and with p‐nitrophenol phosphate sodium salt for HL, PM and HLS. In results of experiment 1 proportion of HC showing AP activity increased 1–2 h, then returned to normal after 4 h. However, in B. bassiana‐injected grasshoppers, a second increase was noted 24 h later which was not seen in the Tween‐80‐injected insects. Uninjected controls showed no change with time in the proportion of HC with AP activity.Studies were also made of the distribution of AP activity in the HL, PM, and HLS. AP activity in HL appeared to vary with the sex of the grasshoppers. Females showed increase in AP activity in HL 18–24 h after injection with B. bassiana, whereas males only showed an increase 1 h after injection. Assay of HLS showed that the level of AP activity did not change significantly throughout the experiment. Changes in AP activity in PM, in both B. bassiana – and Tween‐80‐injected insects (both sexes) paralleled those of the HL, indicating that the enzyme is released from the HC. The observations are discussed in terms of the possible role of AP in the immune response of M. sanguinipes.
Influence of microbe‐associated parthenogenesis on the fecundity of Trichogramma deion and T. pretiosum
Authors: Stouthamer R. , Luck R. F. 
Published: April 2011

AbstractMicrobe‐associated parthenogenesis (thelytoky) has been discovered in nine Trichogramma species, parasitoids of mainly lepidopteran eggs. Parthenogenetic and bisexual conspecifics co‐occur in many field populations. As an initial step to understand the dynamics of these two reproductive strategies we studied the effect of microbe‐associated parthenogenesis on fecundity. The fecundity of two parthenogenetic isofemale lines of T. pretiosum and one of T. deion was compared with bisexual lines derived from them by antibiotic treatment. In all three cases parthenogenetic females were less fecund over their lifetime than bisexual females. Also, parthenogenetic females produced fewer daughters in two cases and in one case a similar number of daughters as their respective bisexual counterparts. The lack of mating and insemination was excluded as an explanation for the reduced fecundity of parthenogenetic females, because mated and virgin parthenogenetic females produce the same number of offspring. Antibiotic treatment can also be excluded because females of field‐collected bisexual line treated with antibiotics produced the same number of offspring as untreated females. The reduced fecundity of parthenogenetic females was caused by a lower number of eggs being laid rather than by a greater developmental mortality. Parthenogenetic females produced less daughters than bisexual females when host availability was not limiting, but when host availability was severely limited, parthenogenetic females produced more daughters than the bisexual females.
Existence d'une phéromone sexuelle chez Caryedon serratus: attractivité des femelles et réactivité des mâles
Authors: Chaíbou M. , Pierre D. , Biémont J. C. , Pouzat J. 
Published: April 2011

RésuméLes femelles de Caryedon serratus (Ol.) produisent, pendant la scotophase, une phéromone sexuelle volatile qui déclenche chez les mâles une chémoanémotaxie positive. Les effets de l'âge sur l'attractivité des femelles et sur la réactivité des mâles ont été étudiés. Plus de soixante‐dix pour cent des mâles commencent à réagir à la phéromone sexuelle dès les premières 24 heures qui suivent leur émergence. Une seule femelle sur 31 a été attractive à cet âge. A 48 heures, le pourcentage des femelles attractives est de 38,7%. Il existe une variabilité inter et intra femelles dans la production de phéromone sexuelle (début, régularité).L'existence des récepteurs antennaires à la phéromone sexuelle chez le mâle est montrée par des études électrophysiologiques (EAG). La variabilité de la production de phéromone sexuelle est discutée.SummaryExistence of sex pheromone in Caryedon serratus (OL): female attractiveness and male reactivityThe female of Caryedon serratus release, from the beginning of scotophase, a sex pheromone witch triggers a positive chemoanemotaxy in males. The effects of age on female attractiveness and on male reactivity are studied. About 70.37% of males begin to react to the sex pheromone within the first 24 h after emergence. At this age, only one female out of 31 is attractive. At 48 h, the percentage of attractive females is 38.7%. There is inter and intra‐female variation in sex pheromone production (beginning, regularity). The existence of receptors on male antennae for this pheromone is shown by electrophysiology (EAG). The variability in sex pheromone production is discussed.
Behavioural responses of three stored product Coleoptera species to extract of carob (Locust bean), Ceratonia siliqua
Authors: Obeng‐Ofori D. 
Published: April 2011

AbstractThe behavioural responses of Cryptolestes pusillus, Oryzaephilus surinamensis and Prostephanus truncatus to different doses of carob extract were assessed in a two‐choice pitfall bioassay and in plastic grain probe traps. The extract evoked a quick directional response and induced high beetle attraction to treated pitfall arenas compared with the controls. Overall, the extract improved probe trap efficiency by about 50% compared to unbaited probes. Beetle response was dose‐dependent with the medium dose of 10 μl probably eliciting optimum response.
Performance of nymphal and adult southern green stink bug on an overwintering host plant and impact of nymph to adult food‐switch
Authors: Panizzi Antônio R. , Saraiva Sílvia I. 
Published: April 2011

AbstractPerformance of nymphs and adults of the southern green stink bug, Nezara viridula (L.) (Heteroptera: Pentatomidae) feeding on immature fruits of radish, Raphanus raphanistrum L. (Brassicaceae) was poor compared with feeding on immature soybean [Glycine max (L.) Merrill] pods, but a change from radish to soybean from nymph to adult alleviated some of the detrimental effects of this food on adult performance. Over 50% of nymphs died on radish, while only 15% died on soybean. To complete nymph development (stadia 2 through 5), male and female nymphs required 9.5 and 13.3 days longer on radish compared to soybean. Fresh body weight of 1‐d‐old adult females and males was ⋍65% greater for those reared as nymphs on soybean than on radish, with females being significantly heavier than males on both foods. Survivorship and longevity of females, however, was greater for those fed on radish as nymphs and as adults, as compared to those that fed on soybean or radish followed by soybean. Males lived longer when fed exclusively on soybean. In general, reproductive performance and percentage gain in adult body weight was greatest for insects fed on soybean only, and were better for those whose food was switched from nymph to adult, as compared to those insects fed on radish solely.
Realized heritability of resistance to dicrotophos in greenhouse whitefly
Authors: Omer Amir D. , Tabashnik Bruce E. , Johnson Marshall W. , Leigh Thomas F. 
Published: April 2011

AbstractRealized heritability (h2) of resistance to dicrotophos in greenhouse whitefly, Trialeurodes vaporariorum Westwood, was estimated from a laboratory selection experiment. Five generations of selection increased the LC50 approximately 13‐fold. Estimated h2 of resistance to dicrotophos was 0.40 when calculated with the method of Tabashnik (1992) and 0.35 with the method of Tanaka & Noppun (1989). These results suggest that 35 to 40% of the total phenotypic variation in resistance was caused by additive genetic variation. For thirteen previously reported estimates of h2 of insecticide resistance in other insect pests, the mean was 0.29. The relatively high h2 of dicrotophos resistance for T. vaporariorum is consistent with rapid resistance development in field populations.
Cold‐tolerance of the oriental cockroach Blatta orientalis
Authors: le Patourel G. N. J. 
Published: April 2011

AbstractThe cold‐hardiness of nymphal stages 1 to 5 and adult male and female Blatta orientalis was tested at 2°, −5° and −10 °C. The LT50 (time) of insects exposed to −5° ranged from 0.21 to 0.43 days. Acclimation at 10 °C for times varying up to 14 days progressively increased cold‐hardiness. A 14 day acclimation at 10° prior to exposure at −5°C increased LT50 (time) to 1.1–4.2 days for the various stages; prolonging the acclimation time to 28 days produced no further increase in LT50. All stages were rapidly killed at −10 °C (LT50<0.04 days) and survived prolonged exposures at 2 °C (LT50s from 16 to > 42 days) following acclimation. The potential for survival of outdoor populations of B. orientalis over winter is discussed.
Sex pheromone traps for monitoring the codling moth: effect of dispenser type, field aging of dispenser, pheromone dose and type of trap on male captures
Authors: Kehat M. , Anshelevich L. , Dunkelblum E. , Fraishtat P. , Greenberg S. 
Published: April 2011

AbstractThe effects of dispenser type, dispenser aging in the field, pheromone dose in the dispenser and trap type on trapping efficiency of codling moth, Cydia pomonella (L.), males were investigated in Israel. An Israeli‐manufactured rubber septum was significantly better than the CM Pherocon cap in attracting males to a Pherocon 1C cap trap or an IPS trap. The effect of aging of the dispenser in the field on trapping efficiency was significant in CM Pherocon caps and the Israeli septa. Captures in traps were negatively correlated with aging of septa. The effect of aging of dispensers was more marked during summer than during spring. The fairly rapid loss of attractancy indicates that the lures should be replaced after 2 weeks at the most. The release rate of the pheromone from the dispensers was measured in a flow system. The emission from the Israeli septa and Pherocon caps decreased sharply after 2 weeks and then was almost constant, which explains the lower attractancy of aged septa. However, there was a marked difference in the release profiles of the pheromone from the two types of dispensers, which may explain the different performance of the two dispensers. Within the range of 0.1 to 100 μg pheromone per dispenser, male response increased positively with the pheromone dose. Pheromone loadings of 100 or 1000 μg per dispenser did not differ significantly in their attractiveness for males. A load of 5000 μg per dispenser was significantly less attractive to males than was 100 or 1000 μg per dispenser. The non‐sticky IPS trap was significantly better in capturing codling moth males than was the sticky, commonly used Pherocon 1C trap, provided it was baited with the Israeli dispenser. The two traps were equally effective when baited with the CM Pherocon caps. The possibility of using the non‐sticky, nonsaturating and easy‐to‐handle IPS traps for monitoring codling moth is of great importance.
Locating a resistance mechanism to the cabbage aphid in two wild Brassicas
Authors: Cole R. A. 
Published: April 2011

AbstractFeeding behaviour of the cabbage aphid, Brevicoryne brassicae, was monitored electronically on two resistant Brassica species, B. fruticulosa and B. spinescens, and compared with a susceptible control B. oleracea var. capitata cv. Offenham Compacta. Aphids, monitored for 10 h on the under side of leaves, performed recognizable feeding behaviour on all species. Electrical Penetration Graphs (EPGs) of aphids on resistant and susceptible plants showed no difference in behaviour for aphids on resistant Brassica species compared to susceptible until stylets penetrated the phloem sieve elements when a large reduction in the duration of passive phloem uptake (E2 pattern) on B. fruticulosa was indicated. Although feeding behaviour on 6 week‐old plants of B. spinescens was similar to the susceptible controls, behaviour on 10 week‐old plants was similar to that recorded for B. fruticulosa. The mechanism of resistance is thought to be located in the sieve element as the normal sieve element salivation (E1 signal was either quickly terminated by withdrawal of the stylets from the sieve element or continued as a disrupted E2 pattern. Analysis of secondary plant compounds in the three Brassica species only identified significant differences in the glucosinolate profile. No reproducible differences were detected in the concentration of phenolics or anthocyanins. The major glucosinolate component of B. fruticulosa and B. spinescens was gluconapin rather than glucobrassicin and glucoiberin as found in the susceptible host plant. However, both pure glucosinolates and glucosinolate extracts from all three species did not reduce aphid survival on chemically‐defined artificial diets. These results suggest that the mechanism of resistance may be a mechanical blocking of the sieve element or stylets rather than a difference in the secondary plant chemistry of glucosinolates and phenolics.
The effects of azadirachtin‐treated diets on the feeding behaviour and fecundity of the peach‐potato aphid, Myzus persicae
Authors: Nisbet A.J. , Woodford J.A.T. , Strang R.H.C. 
Published: April 2011

AbstractAdult apterous Myzus persicae, which had fed for 26 h on diet containing azadirachtin at concentrations of 25–100 ppm, produced nymphs at less than half the rate of aphids on control diets. After 50 h on azadirachtin‐treated diets nymph production had virtually ceased. After this period, any nymphs produced by adults that had fed on azadirachtin‐treated diets were born dead with undeveloped appendages. Honeydew production on azadirachtin‐treated diets was unaffected during the first 26 h period but was approximately three times less than on control diets during the subsequent 24 h period.
Larvicidal activity of lectins on Lucilia cuprina: mechanism of action
Authors: Eisemann C. H. , Donaldson R. A. , Pearson R. D. , Cadogan L. C. , Vuocolo T. , Tellam R. L. 
Published: April 2011

AbstractLarvae of the blowfly Lucilia cuprina (Wied.) (Diptera: Calliphoridae) were grown in vitro on a serum‐free medium in the presence of a number of lectins. Lectins with specificities for β‐(1,4)‐N‐acetylglucosamine (wheat germ lectin) and α‐D‐mannopyranosyl and (α‐D‐glucopyranosyl residues (lentil lectin and Con A) caused strong concentration‐dependent inhibition of the growth of the larvae and substantial mortality. Wheat germ lectin had the strongest effects, showing 50% inhibition of larval growth at a concentration of 2 μM and 100% mortality at 25 μM. Other lectins with different sugar specificities had much less effect. The mechanism of the larvicidal action(s) of wheat germ lectin, lentil lectin and Con A was investigated. There were at least three effects of these lectins on L. cuprina larvae. First, these lectins bound to and reduced the permeability of the peritrophic membrane of the larvae. Second, they reduced ingestion of diet medium by larvae. Third, the lectins also bound to the apical membranes of larval gut epithelial cells although there were no obvious signs of damage to these cells. It is concluded that the combination of these effects probably results in the starvation of the larvae. The implications of these results in terms of possible control strategies for L. cuprina are discussed.
Interactive effects of rutin and constant versus alternating temperatures on performance of Manduca sexta caterpillars
Authors: Stamp N. E. 
Published: April 2011

AbstractThe effects of different concentrations of rutin and constant temperature (20 °C) versus alternating temperatures (23:15 °C) on growth, molting and food utilization efficiencies of third instar tobacco hornworms (Manduca sexta) were determined. Relative consumption rate (RCR) and relative growth rate (RGR) were significantly higher for larvae at the alternating thermal regime compared to those at the constant (representing the average) temperature. With increasing concentrations of rutin, the negative effect of rutin on RCR and RGR increased for the larvae in the alternating thermal regime; however, at the constant temperature, rutin had little effect. The alternating thermal regime promoted synchrony in the timing of spiracle apolysis (the earliest morphological marker of molt). Rutin disrupted that synchrony. I discuss how patterns of host plant resistance may be altered with a decrease in amplitude of diurnal temperatures (as has been documented recently for temperate regions) through the uncoupling of herbivore performance and allelochemical concentration. I conclude that simultaneous consideration of fluctuating temperatures and allelochemicals is advisable when assessing the effects of temperature and allelochemicals on performance of insect herbivores because interactive effects between temperature and dietary components occur and perhaps are common.
Temperature dependent functional response of Encarsia formosa parasitizing the Poinsettia‐strain of the cotton whitefly, Bemisia tabaci, on Poinsettia
Authors: Enkegaard Annie 
Published: April 2011

AbstractThe control efficiency and performance of Encarsia formosa Gahan (Hymenoptera: Aphelinidae) as influenced by the density of its host, the Poinsettia‐strain of Bemisia tabaci Gennadius (Homoptera: Aleyrodidae), were investigated by laboratory experiments on Poinsettia (Euphorbia pulcherrrima Willd.). E. formosa showed a Type II functional response to fourth instar larvae of B. tabaci, the response plateau increasing with temperature. A response model for randomly searching parasitoids incorporating temperature‐dependent handling time and temperature‐independent search rate was in accordance with the results, and gave an estimated search rate of 0.033 leaf·hour−1 and handling times of 1.54, 2.86 and 20.1 h at 28 °C, 22 °C and 16 °C, respectively. From the latter, the maximum number of hosts that can be parasitized at the three temperatures are 10.4, 5.6 and 0.8 larvae per day (provided the light period is 16 h). The number of hosts with ovipositor punctures was higher than the number of parasitized hosts, especially at 22 °C and 28°C, implying that E. formosa refrains from laying eggs in some of the hosts examined with the ovipositor. About 31% of the punctured larvae did not contain any eggs. Superparasitism occured during the experiment presumably originating from young, inexperienced parasitoids. Individual larvae were occasionally punctured several times, also by non‐superparasitizing E. formosa. The resulting distribution of ovipositior holes was random, indicating that E. formosa on the basis of antennal testing is unable to determine if a larva has previously been examined with the ovipositor. Almost fifty percent of the punctures were not followed by egg‐depositions. Besides parasitization E. formosa used hosts as food source. The number of hostfed larvae was independent of density, but varied with temperature being highest at 28 °C (0.12 hostfed larvae per parasitoid per day).
Diel activity pattern of a nocturnal moth, Zeiraphera canadensis, in nature
Authors: Quiring Dan T. 
Published: April 2011

AbstractThe spruce bud moth, Zeiraphera canadensis Mutt & Free. (Lepidoptera: Tortricidae), displayed a bimodal activity pattern in two young white spruce, Picea glauca (Moench) Voss, plantations. During the day, when temperatures were highest and relative humidities lowest, most moths remained in the lower crown, presumably in response to the risk of hygrothermal stress and/or predation. Flight activity peaks occurred near dawn and dusk. Moths moved higher in the crowns shortly after sunset and many were observed flying above the tree canopy. This activity peak was associated with oviposition and mating. Oviposition started at sunset and continued for approximately 3 h. Females probed oviposition sites with their ovipositor before ovipositing, suggesting that they use sensillae on the ovipositor to evaluate potential oviposition sites. Most mating occurred between 22:00 and 04:00 h. Males hovered adjacent to branches containing females before alighting. After alighting, males usually approached to within 2–5 cm of females and then remained motionless for a short time before attempting mounting, indicating that some short‐range communication usually occurs prior to mating. Reduced flight activity between midnight and dawn was not due to low temperatures, which were above the minimal temperatures for flight for males (10 °C) and females (12 °C) determined in the laboratory.
Toxicity of diflubenzuron and pyriproxyfen to the predatory bug Podisus maculiventris
Authors: De Clercq P. , De Cock A. , Tirry L. , Viñuela E. , Degheele D. 
Published: April 2011

AbstractThe susceptibility of the predatory pentatomid Podisus maculiventris (Say) to the insect growth regulators (IGRs) diflubenzuron and pyriproxyfen was investigated in the laboratory. Fifth‐instar nymphs were exposed to formulated materials of each compound via direct contact, residual contact and ingestion. Diflubenzuron was harmless to P. maculiventris by direct and residual contact, but was highly toxic when ingested via drinking water. Pyriproxyfen caused severe deformities at ecdysis whatever the method of exposure. Exposure of fifth instars to sublethal concentrations (around LC10) of both compounds had no adverse effects on reproduction of emerging adults. The data suggest that the use of these IGRs in the integrated management of insect pests should be evaluated with caution.