bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insect growth regulating effects of neem extract and azadirachtin on aphids
Authors: Lowery D. Thomas , Isman Murray B. 
Published: April 2011

AbstractNeem, Azadirachta indica (A. Juss.), seed oil (NSO) applied to leaf discs at a concentration of 1.0% resulted in 94% to 100% mortality of second instar nymphs of currant‐lettuce aphid, Nasonovia ribis‐nigri (Mosley), and green peach aphid, Myzus persicae (Sulzer), after nine days. The equivalent amount of pure azadirachtin (AZA) (ã40 ppm), the principle active ingredient of neem, was as effective as NSO. The survival of adult aphids was unaffected by NSO or AZA, but the survival of offspring from treated adult M. persicae and N. ribis‐nigri was reduced significantly. The lethal concentration of AZA resulting in 50% mortality of second instar nymphs of nine species of aphids ranged from 2.4 ppm for M. persicae on pepper to 635.0 ppm for the strawberry aphid, Chaetosiphon fragaefolii (Cockerell), on strawberry. For M. persicae, the growth regulating effect of AZA was influenced by the host plant and the nymphal instar treated.
Isolation of a chitin‐binding lectin, with insecticidal activity in chemically‐defined synthetic diets, from two wild brassica species with resistance to cabbage aphid Brevicoryne brassicae
Authors: Cole R. A. 
Published: April 2011

AbstractA lectin, with a chitin‐binding domain and chitinase activity, is present in significant quantities in the wild brassica species B. fruticulosa and B. spinescens but at low levels in cultivated cabbage cv. Offenham Compacta. The lectin, purified > 1000 fold after binding to chitin, migrated on SDS ‐ PAGE gels as a single band with a Mr of 14.500. The amino acid composition of the lectin from B. spinescens indicated high concentrations of asparagine/aspartic acid, glycine, leucine and serine in common with other chitin‐binding lectins with insecticidal and antifungal activities. Brassica lectin and the closely related agglutinin from wheatgerm and nettle show significant insecticidal activity when presented to Brevicoryne brassicae in chemically‐defined synthetic diets.
Behavioral responses of Colorado potato beetle larvae to combinations of temperature and insolation, under field conditions
Authors: Lactin Derek J. , Holliday N. J. 
Published: April 2011

AbstractIn short‐term field trials at combinations of ambient temperature (°C) and insolation (W·m−2), larval Colorado potato beetles (Leptinotarsa decemlineata [Say] [Coleoptera: Chrysomelidae]) were observed after their release on the adaxial surface of leaflets on potato plants (Solanum tuberosum L. Solanaceae). The larvae either began feeding or moved under the leaflet; mean interval from release to expression of these behaviors (2.9 ± 0.05 min [n = 358]) was independent of air temperature and insolation. Proportion of larvae moving under the leaflet increased logistically with both air temperature and insolation. A 1 W·m−2 change in insolation (P) evoked the same effect on this proportion as a 0.0838 °C change in air temperature (Ta), so the two quantities were combined as T* = Ta + P · 0.0838 °C/(W·m−2), which has units of °C. The proportion of larvae moving under the leaflet increased logistically with T*.In 1‐day field trials we monitored air temperature, insolation and proportion of larvae under the leaflet, and compared the latter to predictions from the logistic regression derived from the short‐term trials. Consistently more larvae occurred under leaflets than predicted from the logistic regression; this bias diminished as T* increased until at T* > 40 °C, observed and predicted proportions were equal. This pattern of deviation from the predictions of the logistic regression is consistent with a thermoregulatory strategy in which larvae move away from hostile conditions, rather than seek optimal conditions.
Sex differentiation studies relating to releaser aggregation pheromones of the desert locust, Schistocerca gregaria
Authors: Obeng‐Ofori D. , Njagi P. G. N. , Torto B. , Hassanali A. , Amiani H. 
Published: April 2011

AbstractBehavioural responses of nymphs and adults in the gregarious phase of the desert locust, Schistocerca gregaria (Forskal) (Orthoptera: Acrididae) were investigated in a single‐chamber bioassay system to a choice of two columns of air, one permeated with airborne volatiles emanating from either sex of nymphs or adults and the other untreated. There was no sexual differentiation in the production of or response to nymphal volatiles. Young adults of either sex did not produce a stimulus with significant activity. Of the older adults, only the males produced the aggregation stimulus to which both sexes were equally responsive. Charcoal‐trapped volatiles from the two sexes of nymphs and adults evoked similar aggregation responses. Antennae of the older adults showed significantly higher EAG responses than those of fifth instar nymphs to all four volatile collections, of which volatiles from older adult males were the most stimulatory and evoked the highest EAG amplitudes.
Composition and variability of the saliva of coreids in relation to phytoxicoses and other aspects of the salivary physiology of phytophagous Heteroptera
Authors: Taylor G. S. , Miles P. W. 
Published: April 2011

AbstractIn the saciform, principal salivary glands of Mictis profana (Fabr.) (Coreidae: Heteroptera, Pentatomorpha), the contents of all lobes other than the posterior form gels consistent with their contributing to the solidifying saliva (stylet sheath); the posterior lobe secretes most if not all of a sucrose‐hydrolysing enzyme that occurs in the nongelling (watery) saliva. Evidence for the occurrence of such an enzyme in the saliva of other coreids is presented. That in M. profana has a pH optimum near neutral and a substrate specificity consistent with sucrase (sucrose α ‐D‐glucohydrolase, EC 3.2.1.48) as distinct from plant invertase (β ‐D‐fruccofuranosidase, EC 3.2.1.26). Apart from some maltose‐hydrolysing activity in the salivary glands, also consistent with sucrase, no other carbohydrases and neither proteinase nor lipase were detected. Phosphatases were found in gland extracts but not in secreted saliva. The saliva contains catechol oxidase (EC 1.10.3.1) from the accessory gland and ducts. Topical application of pilocarpine caused individual M. profana to secrete up to 58 μl watery saliva which showed continuous and independent variation of sucrase activity (up to ca 0.012 Units/μl) and pH (6–8), although high sucrase content tended to coincide with high pH. Total protein varied up to 10 μg/μl, and free amino acids up to 1.8 μg/μl leucine eq. Of the many proteins and/or protein subunits separable by electrophoresis of gland contents and saliva, four had sucrase activity, the most mobile with MW ca 66000. TLC indicated inter alia phenyl alanine and tyrosine, but no DOPA nor other diphenolic substrates of the catechol oxidase in the watery saliva. The soluble components of the saliva, which also has marked surfactant properties, are discussed in relation to the feeding process of coreids and the characteristic lesions they produce in their food plants.
Effects of intercropping white cabbage with clovers on pest infestation and yield
Authors: Theunissen J. , Booij C. J. H. , Lotz L. A. P. 
Published: April 2011

AbstractDuring two consecutive years the effects of intercropping fresh market white cabbage with two species of clover on pest populations and yield were studied. White cabbage cv. Minicole was intercropped with Trifolium repens (white clover) and Trifolium subterraneum (subterranean clover) as compared to the monocrop. During the season observations were made on pest population developments, especially of Mamestra brassicae L. (cabbage moth), Brevicoryne brassicae L. (cabbage aphid), Delia brassicae L. (cabbage root fly), and evaluation of caterpillar feeding injury. At harvest the yield in quantity and quality was determined to be able to assess the gross financial result. Intercropping effects in terms of suppression of oviposition and larval populations of various pests were found. Although no pesticides were used and competition reduced the weight, the quality of the intercropped cabbages lead to a better financial result compared to the monocropped cabbage crop. The results are discussed in the perspective of the practical implications in the context of IPM.
Plant growth stage effects on the feeding and growth responses of the bertha armyworm, Mamestra configurata to canola and mustard foliage
Authors: McCloskey Catherine , Isman Murray B. 
Published: April 2011

AbstractMamestra configurata (Walker) (Lep., Noctuidae) larvae were fed excised Brassica juncea (commercial brown mustard) or B. rapa cv. Tobin (Canola) foliage of three plant growth stages ‐ rosette (stage 2), stem elongation (stage 3) and flowering (stage 4). Relative consumption rates (RCRi) were not significantly different between the plant species. Within the B. juncea treatments, there were no significant growth stage differences in RCRi. However, within B. rapa, RCRi increased with advancing plant growth stage. Larvae fed B. juncea foliage had significantly reduced relative growth rates (RGRi) compared to larvae fed B. rapa foliage. Within the B. juncea treatments, RGRi decreased with advancing plant growth stage. There were no significant growth stage differences in RGRi in the B. rapa treatments. RGRi was inversely proportional to the levels of isothiocyanate‐releasing glucosinolates in the B. juncea treatments. RCRi was inversely proportional to the levels of indolyl glucosinolates in the B. rapa treatments. Levels of total phenols and catechols in B. juncea did not show any trend which could be related to growth stage effects in the insect nutritional indices. In B. rapa, levels of phenols and catechols in stage 3 and 4 foliage were lower than that of stage 2 foliage. Analyses of total nitrogen in field‐grown plants showed reductions in percent nitrogen from rosette to flowering stage foliage. The response of M. configurata to different growth stages of its host plants are discussed in relation to changing levels of allelochemicals and nitrogen.
The effect of host instar on the size and sex ratio of the endoparasitoid Dacnusa sibirica
Authors: Croft P. , Copland M. J. W. 
Published: April 2011

AbstractOlder instars of the leafminer host Chromatomyia syngenesiae Hardy (Diptera: Agromyzidae) at parasitization resulted in larger female adults of the larval‐pupal endoparasitoid Dacnusa sibirica Telenga (Hymenoptera: Braconidae). The sex ratio in the parasitoid offspring became increasingly female biased and development period decreased with increasing age of the host at parasitization. Older host instars were therefore considered to produce a fitter parasitoid.
Variation among Eucalyptus species in resistance to eucalyptus longhorned borer in Southern California
Authors: Hanks Lawrence M. , Paine Timothy D. , Millar Jocelyn G. , Hom John L. 
Published: April 2011

AbstractEucalyptus L'Héritier (Myrtaceae: Leptospermoideae) species are native to the Austro‐Malaysian region, but have been widely planted in temperate and subtropical regions around the world. In most regions where Eucalyptus have been imported, the Eucalyptus Longhorned Borer (Phoracantha semipunctata F.) (Coleoptera: Cerambycidae) has been accidently introduced. Larvae of the beetle bore through the bark and mine along the cambium of stressed trees, usually killing their host. We report here the relative susceptibilities of 12 Eucalyptus species in two mixed‐species plantations in California, USA. These trees were stressed by water deficit resulting from a prolonged drought. Eucalyptus species that appeared resistant to the borer included E. camaldulensis Dehnhardt, E. cladocalyx F. Muller, E. sideroxylon A. Cunn. ex Woolls, and E. trabutii (an E. camaldulensis hybrid). Species that were more susceptible to attack were E. diversicolor F. Mueller, E. globulus LaBillardière, E. grandis Hill ex Maiden, E. nitens (Deane & Maiden), E. saligna Sm., and E. viminalis LaBillardière. Survival of trees was influenced by fine‐scale moisture variation resulting from slope and irrigation effects. Resistance characteristics of these Eucalyptus species did not correlate with taxonomic relatedness or bark characteristics, but did correspond to drought tolerance traits in their native habitat. Eucalyptus species that were resistant to attack by P. semipunctata were those that are most tolerant of drought in Australia.
Identification and field optimisation of the female sex pheromone of the rice leaffolder, Cnaphalocrocis medinalis in India
Authors: Rao A. Ganeswara , Reddy D. D. R. , Krishnaiah K. , Beevor P. S. , Cork A. , Hall D. R. 
Published: April 2011

AbstractAnalysis of ovipositor washings from virgin female Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae) of Indian origin by linked gas chromatography and electroantennography indicated the presence of three electrophysiologically‐active compounds. These were identified on the basis of their gas chromatographic retention times and mass spectra as (Z)‐11‐hexadecenyl acetate, (Z)‐13‐octadecenyl acetate and (Z)‐13‐octadecen‐1‐ol with (Z)‐13‐octadecenyl acetate present in amounts of between 0.25 and 1.5 ng per ovipositor and the other two components at less than 10% of this. Trace quantities of octadecyl acetate were identified by mass spectrometry but no electroantennographic responses were observed to this compound. Field trials conducted with a range of blends of the three electrophysiologically‐active compounds showed that blends containing between 5% and 30% (Z)‐11‐hexadecenyl acetate in (Z)‐13‐octadecenyl acetate dispensed from either white rubber septa or polythene vials were more attractive to male moths than a virgin female moth. Addition of (Z)‐13‐octadecen‐1‐ol reduced attractiveness to male moths in the blends and concentrations tested.
The use of visual cues in host evaluation by aphidiid wasps
Authors: Michaud J. P. , Mackauer M. 
Published: April 2011

AbstractWe examined host evaluation behaviour in three species of aphid parasitoids, Ephedrus californicus Baker, Monoctonus paulensis (Ashmead), and Praon pequodorum Viereck (Hymenoptera: Aphidiidae). Mated females were provided with pairwise choices among three kinds of hosts in the laboratory: (green) pea aphid, Acyrthosiphon pisum (Harris), and a green and a pink colour morph of alfalfa aphid, Macrosiphum creelii Davis. Patterns of attack and host acceptance were species‐specific. Females of E. californicus did not respond to the presence of aphids prior to making antennal contact. Variations in rates of parasitization (pea aphid>green alfalfa aphid>pink alfalfa aphid) were consistent with differences in aphid defensive behaviours; no ‘preference’ for any host type was evident when aphids were anaesthetized with carbon dioxide. In M. paulensis, the order of preference (pea aphid>green alfalfa aphid>pink alfalfa aphid) did not vary when aphids were immobilized, or presented in the dark, or both. Host movement did not influence the rate of attack by M. paulensis. In contrast, the ranked order of preference in P. pequodorum varied with circumstance. In the light, females attacked pea aphid and green alfalfa aphid with equal frequency, but parasitized significantly more of the former; both kinds of aphids were attacked and parasitized at higher rates than pink alfalfa aphid. In the dark, P. pequodorum females parasitized green and pink alfalfa aphids equally and at higher rates than pea aphids. Whereas E. californicus was more successful ovipositing in immobilized hosts, P. pequodorum females attacked and laid more eggs in normal than anaesthetized aphids. Patterns of host recognition and evaluation are compared across six species representing four genera in the family Aphidiidae.
Does time spent on adult bees affect reproductive success of Varroa mites?
Authors: Boot Willem J. , Calis Johan N. M. , Beetsma Joop 
Published: April 2011

AbstractReproduction of Varroa jacobsoni Oudemans (Acari: Varroidae) and the number of Varroa mites that were found dead on the bottom board of the hive, were studied in relation to the period the mites spent on adult honey bees, Apis mellifera L. (Hymenoptera: Apidae), prior to invasion into brood cells. The maximum period on adult bees was 23 days. To introduce mites, combs with emerging worker brood, heavily infested with mites, were placed into a colony and removed the next day. At the beginning of the first day following emergence from brood cells, 18% of the mites introduced into the colony was found on the bottom of the hive. Part of these mites may already have died inside the capped brood cells, and then fallen down after cleaning of cells by the bees. At the second and third day following emergence, respectively 4% and 2% of the mites on adult bees at the previous day was recovered on the bottom, whereas from the fourth day on only 0.6% of the mites on adult bees was recovered on the bottom per day. After invasion into brood cells, 8–12% of the mites did not produce any offspring. Of the mites that did reproduce, the total number of offspring was 4.0–4.4 per mite during one reproductive cycle, part of which may reach maturity resulting in 1.2–1.3 viable daughters, and 8–10% of the mites produced only male offspring. Reproduction was independent of the period the mites had spent on adult bees prior to invasion into brood cells.
Quality assessment of Trichogramma brassicae in the laboratory
Authors: Cerutti F. , Bigler F. 
Published: April 2011

AbstractThe quality of 52 populations of the egg‐parasitoid Trichogramma brassicae Bezdenko (Hymenoptera, Trichogrammatidae) (synonymous to T. maidis Pint. et Voegele) has been compared by investigating seven parameters in each population. The parameters assessed were: emergence rate, sex ratio, ratio of deformed females, life‐span, walking activity, fecundity on the factitious host eggs and fecundity on the natural host eggs. The last parameter is used as an indirect measure of the acceptance and suitability of the natural host eggs. Origin, history and treatment of each population were known and used as information for interpreting the quality. For computing and presenting the data classical descriptive statistics as well as graphical methods (profile symbol) were applied. Principal Component Analysis and cluster analysis were used for dividing the populations into groups with similar properties.From the results we conclude: a) Strains of the same species, reared under similar conditions, differ in quality. b) Storage and shipment often have a negative impact on quality. c) Crossbred isolated populations showed a lower quality than the parental populations.A synoptical presentation of many parameters assessed on a high number of populations (strains, biotypes, species) is best accomplished by combining profile symbol plots, Principal Component Analysis and cluster analysis.
Evaluation of four aphidiine parasitoids for biological control of Aphis gossypii
Authors: van Steenis M. J. 
Published: April 2011

AbstractFour aphidiine parasitoid species (Hymenoptera: Braconidae) were evaluated with respect to their potential to control Aphis gossypii Glover (Homoptera: Aphididae) in glasshouse cucumbers. In a laboratory experiment thirty cotton aphids were offered to individual females for two hours. Aphidius matricariae Haliday parasitized less than six percent of the aphids and was ruled out as potential biological control agent. Ephedrus cerasicola Starý and Lysiphlebus testaceipes Cresson parasitized 23 and 26 percent of the aphids, respectively. Aphidius colemani Viereck parasitized 72 to 80 percent of the aphids.With the latter three species, experiments were performed in small glasshouses with cucumbers (Cucumis sativus L. cv. ‘Aramon’). As in the laboratory test A. colemani performed best; significantly more colonies were found and parasitization rates in the colonies were higher by A. colemani than by E. cerasicola and L. testaceipes.Because of the good correspondence between laboratory and glasshouse experiments, it is suggested that bad performance of an aphid parasitoid species in a simple laboratory trial might be sufficient evidence to disregard this species for further tests.
Decay rates for slug antigens within the carabid predatorPterostichus melanariusmonitored with a monoclonal antibody
Authors: Symondson W. O. C. , Liddell J. E. 
Published: April 2011

AbstractThe rate at which prey antigens decay within a predator during digestion must be calibrated, for a given assay system, in order to define the period within which predation must have occurred. Monoclonal antibodies have great advantages in terms of target specificity, but have often in the past demonstrated impractically abbreviated antigen detection periods. However, the DrW‐2D11 monoclonal antibody, which detects all three genera of pest slugs (Mollusca: Pulmonata) in Britain, could clearly identify predation byPterostichus melanariusIlliger (Coleoptera: Carabidae) after 2.5 days at 16 °C, a longer interval than has been recorded for any other monoclonal antibody used in predation studies. The half‐life, detection period and decay rate were calibrated with and without subsequent feeding on alternative prey. Unrestricted feeding on earthworm, following consumption of the slugDeroceras reticulatum(Müller), significantly reduced the decay rate of slug antigens. These results appear to contradict the assumptions, based on previous studies, that indicate reduced digestion rates in response to starvation. Possible reasons for this failure to comply with the predictions of optimal foraging theories are discussed.
Evaluation of neem Azadirachta indica seed extracts and oils as oviposition deterrents to noctuid moths
Authors: Naumann Ken , Isman Murray B. 
Published: April 2011

AbstractApplications of three concentrations of oil‐free neem seed extracts (Azadirachta indica A. Juss; Meliaceae) to cabbage plants in cages did not deter oviposition by individuals of three species of noctuid moths, Trichoplusia ni, Peridroma saucia, and Spodoptera litura. The concentrations used corresponded to 10, 50, and 100 ppm of the main active ingredient, azadirachtin. The total number of eggs laid per female, female longevity, and median day of oviposition were not affected. Sprays of the neem oil‐based insecticide Margosan‐OR, and a 1% aqueous emulsion of a refined neem seed oil similarly had no effect on any of the parameters studied. However, a 1% crude oil emulsion significantly reduced the proportion of eggs laid by S. litura on treated plants. Our results suggest that literature reports of significant neem‐based oviposition deterrence to S. litura are the result of compounds that are removed by higher levels of processing and thus not likely to be found in most commercial neem seed formulations. Sprays consisting of highly processed neem seed extracts, used at concentrations that provide larval control, are unlikely to be generally effective as oviposition deterrents to noctuid pests.
Influence of host plant on the mango mealybug, Rastrococcus invadens
Authors: Boavida C. , Neuenschwander P. 
Published: April 2011

AbstractLife history traits of the mango mealybug, Rastrococcus invadens Williams, were compared between two neighboring mango trees (Mangifera indica L.), one of which was heavily infested and the other slightly infested. On the infested tree, mealybug survival was high because of good feeding conditions and low escape. The pre‐reproductive period of mealybugs on the heavily infested tree was shorter and total offspring production higher than that of mealybugs on the uninfested tree. This significantly affected the intrinsic rate of natural increase and explained the observed differences in population densities among the trees. The results obtained from an additional experiment using juvenile clones from the same two mango varieties, in which environmental factors were uniform, demonstrated the importance of plant genotype on mealybug size and survival.