bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diapause induction in the codling moth, Cydia pomonella: effect of larval diet
Authors: Steinberg S. , Podoler H. , Applebaum S. W. 
Published: April 2011

AbstractThe effect of larval diet on diapause induction in the Israeli strain of the codling moth, Cydia pomonella (L.), was studied in a field trial using intact apple fruits of two varieties: ‘Ana’ (early‐ripening, in the end of June) and ‘Granny Smith’ (late‐ripening, in October). Diapause incidence increased as fruit age (determined as days from fruit‐set) progressed. These results corroborate former studies on other strains of the codling moth, where excised fruits were used.The combination of 80‐day‐old, fully ripe, ‘Ana’ fruit treatment with the longest days of the year, yielded 38% diapause. This result demonstrates that mature fruit (inducing diapause) cannot completely override the effect of long day (averting diapause), but does confirm that larval diet modifies the photoperiodic induction of diapause in the codling moth.
Stylet activities and potato virus Y vector efficiencies by the aphids Brachycaudus helichrysi and Drepanosiphum platanoidis
Authors: Powell G. , Harrington R. , Spiller N. J. 
Published: April 2011

AbstractStylet penetration activities of two aphid species were recorded electrically and compared with their efficiency of potato virus Y transmission. B. helichrysi (Kltb.) acquired the virus during 15% of single penetrations on infected leaves. These acquisitions were associated with the occurrence of cell membrane puncture by stylets, recorded during 44% of the penetrations. D. platanoidis (Schrank) punctured membranes during only 8% of penetrations, and its acquisition efficiency was less than 1%. The frequency with which aphids puncture cell membranes appears to partially determine their vector efficiency.
Onion fly egg distribution in soil: a new sampling method and the effect of two granular insecticides
Authors: Havukkala I. , Harris M. O. , Miller J. R. 
Published: April 2011

AbstractA method for rapidly determining the vertical and horizontal distribution of insect eggs in fragile soil is described. Liquefied agar is allowed to permeate intact soil samples from below; after cooling, the resulting solid is cut into thin sections, from which eggs can be recovered by washes with hot water. This technique revealed that in organic (muck) soil in the laboratory, undisturbed onion flies, Delia antiqua (Meigen) (Diptera: Anthomyiidae), laid 95% of their eggs within a 10 mm diameter zone around the base of a surrogate onion ‘stem’ arising vertically from the soil. Ninety % of all eggs were found in the top 12 mm of soil, with an apparent maximum at depth of 2–4 mm. Increasing fly density from 30 to 200 flies per 30 × 30 × 42 cm cage flattened the horizontal distribution of eggs and extended the ovipositional range from c. 15 mm to beyond 60 mm, suggesting there was competition for the preferred ovipositional sites. Surface treatment of muck soil in the field by granular formulations of the insecticides Lorsban™15 G (active ingredient chlorpyrifos) and Dyfonate™15 G (fonofos) three weeks prior to bioassaying reduced egg‐laying at depths greater than 8 mm. The relation between the measured egg distribution and mortality factors in soil (low moisture and high temperature) is discussed.
Host plant recognition in monophagous weevils: Specialization of Ceutorhynchus inaffectatus to glucosinolates from its host plant Hesperis matronalis
Authors: Larsen L. M. , Nielsen J. K. , Sørensen H. 
Published: April 2011

AbstractCeutorhynchus inaffectatus Gyllenhal (Coleoptera: Curculionidae: Ceutorhynchinae) is a monophagous species feeding only on Hesperis matronalis L. (Cruciferae) in North‐western Europe. Feeding responses of this weevil to five glucosinolates from its host plant were compared with the responses to four glucosinolates from non‐host plants. The major glucosinolates in the host plant were isolated and identified: 6‐methylsulphinylhexylglucosinolate (glucohesperalin), 3, 4‐dihydroxybenzylglucosinolate (glucomatronalin), 3‐O‐apiosylglucomatronalin, a 3, 4‐dihydroxybenzoylester and a 3, 4‐dimethoxybenzoylester of 3‐O‐apiosylglucomatronalin. The three glucosinolates containing apiose were powerful feeding stimulants for C. inaffectatus while the other host plant compounds and allylglucosinolate (sinigrin), 3‐methylsulphinylpropylglucosinolate (glucoiberin), benzylglucosinolate (glucotropaeolin) and p‐hydroxybenzylglucosinolate (sinalbin) were weaker stimulants. The role of glucosinolates in host plant selection of C. inaffectatus and related monophagous crucifer feeders is discussed.
Suppression of Ostrinia nubilalis by Trichogramma nubilale in sweet corn
Authors: Prokrym D. R. , Andow D. A. , Ciborowski J. A. , Sreenivasam D. D. 
Published: April 2011

AbstractWe conducted inundative release experiments with Trichogramma nubilale (Hymenoptera: Trichogrammatidae) to suppress Ostrinia nubilalis (Lepidoptera: Pyralidae) in sweet corn (Zea mays): two experiment during O. nubilalis first generation and three experiments during second generation. Five measurements of ear and stalk damage were used to assess O. nubilalis control in treated and untreated plots within each experimental field. In one experiment during second generation, natural O. nubilalis populations were sufficiently high to demonstrate that the parasitoids (three releases totaling 4.4 million parasitoids per ha) parasitized an estimated 57.4% of the placed O. nubilalis egg masses and reduced the mean number of O. nubilalis larvae per ear by 97.4%, the number of tunnels per stalk by 92.9%, and the number of larvae per stalk by 94.3% in the release plot. Ear damage in this experiment was suppressed to meet acceptable standards for use in cut‐corn commercial processing. Larval mortality was apparently density independent, which implies that density‐dependent larval loss would not compensate for egg parasitism by T. nubilale.
Compensatory response of a legume root‐nodule system to nodule herbivory by Sitona hispidulus
Authors: Quinn M. A. , Hall M. H. 
Published: April 2011

AbstractA laboratory study was conducted to examine the hypothesis that herbivory of nitrogen‐fixing root nodules on legumes causes an exact compensatory response in nodule growth. Plants of Medicago sativa (L.) were grown hydroponically in clear plastic growth pouches so that the number and biomass of root nodules could be estimated nondestructively before, and 10 and 18 days after, partial denodulation. For treatments, plants were subjected to 23% denodulation by first‐instar larvae of Sitona hispidulus (F.) (a common herbivore of Medicago and Trifolium) or 50% nodule pruning; additional plants were left untreated. Results indicated that nodule herbivory and nodule pruning caused an overcompensatory response in number of nodules. This was also true for number of nodule units (an indirect measure of nodule biomass) per plant at 10 days after denodulation but had changed to an exact compensatory response by day 18. An inverse relationship between change in number of nodule units and initial number of nodules indicated that compensatory nodulation was regulated by a feedback mechanism. Shoot and root biomasses were not affected by denodulation in this study.
Response of predatory mites with different rearing histories to volatiles of uninfested plants
Authors: Takabayashi J. , Dicke M. 
Published: April 2011

AbstractThe behavioural response of the predatory mite Phytoseiulus persimilis to volatiles from several host plants of its prey, spider mites in the genus Tetranychus, was investigated in a Y‐tube olfactometer. A positive response to volatiles from tomato leaves and Lima bean leaves was recorded, whereas no response was observed to volatiles from cucumber leaves, or leaves of Solanum luteum and Solanum dulcamara.Different results were obtained for predators that differed in rearing history. Predators that were reared on spider mites (Tetranychus urticae) on Lima bean leaves did respond to volatiles from Lima bean leaves, while predators that had been reared on the same spider mite species but with cucumber as host plant did not respond to Lima bean leaf volatiles. This effect is compared with the effect of rearing history on the response of P. persimilis to volatile allelochemicals of prey‐infested plant leaves.
Intensity and spectral emission as factors affecting the efficacy of an insect electrocutor trap towards the house‐fly
Authors: Roberts A. E. , Syms P. R. , Goodman L. J. 
Published: April 2011

AbstractCompetitive tests were used to determine how the quantitative and spectral characteristics of an electrocutor trap light source affected the attraction of the house‐fly, Musca domestica L. It was found that an increase in the radiant flux (Fe) of the trap lamps due to an increase in radiant area (A), caused a much larger increase in catch than if radiant flux was increased through higher radiant emittance (Me). The results from electroretinograms recorded in response to different levels of Me were consistent with the idea that at a given wavelength the attractiveness of a lamp is attributable to the quantitative output perceived by the fly. Of nine fluorescent lamps, the most attractive had peak emission at 340 nm. A blue lamp (peak emission 419 nm) attracted less than a third as many flies as the UV emitting lamps, and a white lamp (peak emission 585 nm) attracted fewer than a quarter as many. The corresponding photoreceptor responses were measured using the electroretinogram. At wavelengths above 400 nm the attractiveness of a lamp to a fly appears to be lower relatively than the photoreceptor response. Within the ultraviolet region (300 nm–400 nm) attractiveness is again attributable to the quantitative output perceived by the fly. It is concluded that there is a genuine behavioural preference for lamp emissions in the ultraviolet region.
Inducing the sexual forms and hatching the eggs of pea aphids
Authors: Via S. 
Published: April 2011

AbstractIn temperate climates, pea aphids (Acyrthosiphon pisum) produce a single sexual generation each year in response to declining photoperiod and temperature. Mating occurs in the fall and the eggs have an obligatory winter diapause. Genetic recombination during the sexual phase is thought to be an important source of genetic variability within cyclically parthenogenetic aphid populations. Methods for reliably producing sexual forms and hatching the eggs of aphids are therefore central not only to the study of evolutionary change in aphid populations, but also for a general understanding of the origin of agriculturally important variation in destructiveness within pest species.Here, sexual forms of six pea aphid clones were induced in the laboratory and eggs were successfully hatched by creating conditions that closely mimicked those found in field situations. A declining photoperiod was produced by controlling artificial lighting using a timer with variable cycle length. Using these conditions, sexual forms were successfully produced for all six clones tested, which were then mated in all combinations. Eggs were exposed to a daily cycle of freezing and thawing in an incubator under a short‐day photoperiod. Egg hatch averaged 60%, but was as high as 89% for some crosses. These methods will permit testing of evolutionary hypotheses and execution of detailed genetic studies of sources of variability within pea aphid populations. They are thus important tools for both evolutionary and agricultural studies.
Diet, fecundity and egg size in some polyphagous predatory carabid beetles
Authors: Wallin H. , Chiverton P. A. , Ekbom B. S. , Borg A. 
Published: April 2011

AbstractEgg size was measured at different rates of egg laying in three polyphagous carabid species, known to be useful predators of cereal aphids; the small Bembidion lampros Herbst and the medium‐sized Pterostichus cupreus L. and P. melanarius Illiger. Variations in fecundity, as well as the ability of the medium‐sized species to also build up fat reserves, were obtained when beetles were subjected to different dietary regimes consisting of aphids, or foods with a lower or higher protein content. Egg size was found to be dependent on the rate of egg laying within a species. A diet of cereal aphids appeared to be adequate for egg production in these polyphagous carabids, but female P. cupreus were unable to build up fat reserves when they ingested aphids contaminated with the aphicide pirimicarb. Beetles were able to devote resources to more and larger eggs (B. lampros), or to larger eggs and/or fat reserves (P. melanarius/P. cupreus) when given access to a carbohydrate‐rich food with low protein content. The highest rate of egg laying was obtained when female P. cupreus and P. melanarius were given a more varied diet at frequent intervals; including regular shifts between unsprayed aphids, carbohydrate‐rich food and protein‐rich maggots. Within the varied diet treatment a negative relationship was obtained between egg size and egg number among similar‐sized individuals of P. cupreus and P. melanarius; females producing the largest number also laid the smallest eggs. Egg size affected larval survival, since first instars hatching from large eggs were found to survive longer than those hatching from small eggs. The influence of differences in food intake on reproduction, maintenance metabolism, and survival of field‐inhabiting carabids is discussed.
Antiinsectan properties of a novel Fusarium‐derived sterol sulfate
Authors: Dowd P. F. , Burmeister H. R. , Vesonder R. F. 
Published: April 2011

AbstractThe antiinsectan properties of the Fusarium graminearum‐derived novel sterol sulfate, 4, 4, 24‐trimethylcholesta‐8, 14, 24(28)‐trien‐2α, 3β, 11α, 12β‐tetrol 12 acetate, 3‐sulfate were tested on the corn ear‐worm (Heliothis zea (Boddie), the fall armyworm (Spodoptera frugiperda (J. E. Smith), and the driedfruit beetle (Carpophilus hemipterus L.). The sterol sulfate could not be used as a sterol source by any of the insects. The sterol sulfate inhibited growth of S. frugiperda and C. hemipterus larvae at 2500 and 4000 ppm, respectively. Defensive implications of this compound are discussed.
Physical and chemical factors influencing landing and oviposition by the cabbage root fly on host‐plant models
Authors: Košťál V. 
Published: April 2011

AbstractVarious plant models were used in both choice and no‐choice tests in the laboratory to assess landing and oviposition preferences of the cabbage root fly, Delia radicum (L.). The main factor governing the site most suitable for landing was the conspicuousness of the object and not its shape. Oviposition was influenced considerably by the pre‐conditioning of the females. Deprived females laid eggs even when denied access to both host plant chemicals and host‐plant models. The dominant role of contact chemical stimuli in host acceptance was reconfirmed, but only a combination of physical and chemical stimuli appeared capable of eliciting normal oviposition. The combination of contact chemical stimuli and the presence of a stem on the test model had a synergistic effect on the numbers of eggs laid in both choice and no‐choice situations. In choice bioassays, female cabbage root flies distinguished between models of different shapes, heights and sizes. The size and shape of the models appeared to be perceived in part after the flies had landed.
The effect of pre‐acquisition starvation on aphid transmission of potyviruses during observed and electrically recorded stylet penetrations
Authors: Powell G. 
Published: April 2011

AbstractThe effect of pre‐acquisition starvation on stylet penetration behaviour by the aphid Myzus persicae (Sulz.) and the consequent non‐persistent transmission of the potyviruses beet mosaic virus (BMV) and potato virus Y (PVY) were investigated. Visual observations indicated that starved aphids initiated penetrations earlier and penetrated for shorter periods than non‐starved insects. Tethering with a fine gold wire did not affect these observations with either starved or non‐starved aphids, but starvation caused increased PVY and BMV acquisition efficiency, regardless of tethering. Tethered aphids were then made part of an electrical circuit and their stylet activities investigated in detail. Electrically recorded aphids also acquired and inoculated both potyviruses more efficiently when starved, and these acquisitions and inoculations were associated with stylet punctures of plant cell membranes. However, starvation did not affect the occurrence of electrically recorded membrane puncture, suggesting that non‐behavioural factors may contribute to the enhancement of virus transmission by pre‐acquisition starvation.
Electronically monitored feeding behaviour of the lettuce root aphid (Pemphigus bursarius) on resistant and susceptible lettuce varieties
Authors: Cole Rosemary A. , Riggall Wendy , Morgan Alan 
Published: April 2011

AbstractFeeding behaviour of the lettuce root aphid Pemphigus bursarius was monitored electronically on six lettuce varieties. Aphids, monitored for a minimum of 5 h on lettuce roots, performed recognizable feeding behaviour on the susceptible varieties, Webbs Wonderful and Borough Wonder including non probing, pattern A start of new penetration, C (stylet pathway activities) sometimes including clear B‐waves (salivary sheath secretions), potential drops (intracellular penetrations), intracellular E (phloem ingestion) distinguishing E1 and E2 (Tjallingii, 1990) and occasionally xylem ingestion. Although aphid probing was recorded on the resistant varieties Lakeland and Grand Rapids continued penetration to the phloem elements was deterred and the time spent ingesting phloem was short. Aphids rarely probed the resistant varieties Avoncrisp and Avondefiance and all attempted penetrations quickly terminated.
Tissue localisation of lettuce resistance to the aphid Nasonovia ribisnigri using electrical penetration graphs
Authors: van Helden Maarten , Tjallingii W. F. 
Published: April 2011

AbstractElectrical penetration graphs (EPG's) of Nasonovia ribisnigri (Mosley) (Homoptera, Aphididae) on resistant and susceptible lettuce (Lactuca sativa, Compositae) showed a large reduction in the duration of the food uptake pattern (E2) on the resistant line. No differences in EPG's were observed before the phloem was reached. Therefore, resistance is believed to be located in the phloem vessel. Both mechanical blocking of the sieve element after puncturing and a difference in composition of the phloem sap are possible resistance factors. However, a chemical factor seems more likely because of the specificity of the resistance against N. ribisnigri.
Carabid beetle assemblage under diversified agroecosystems
Authors: Athayde Tonhasca Jr.  
Published: April 2011

AbstractCorn (Zea mays L.) and soybean (Glycine max Merrill) were planted in monoculture and strip‐intercropping plots (18.3 times 15.5 m each) under conventional tillage and no‐tillage to create differences in habitat structure. The effects of these agronomic practices on carabid beetle species composition were measured by pitfall‐trap collections during three years. Although neither the number of individuals or number of species were significantly affected by treatments, analyses of variance indicated that four of the six dominant species (75.7% of the total number of carabids captured in three years) responded to tillage treatments. Harpalus pensylvanicus DeGeer and Cyclotrachelus sodalis (LeConte) were more abundant in no‐tillage plots, whereas Pterostichus chalcites Say and Scarites substriatus Haldeman were more common in conventional tillage plots. Pterostichus chalcites was also significantly more abundant in soybean plots than in intercropping or corn plots. H. pensylvanicus, a primarily herbivorous carabid, was the most common species collected. However, P. chalcites, a predaceous carabid, was the dominant species in soybean/conventional tillage plots. The results suggest that characteristics of individual species should be carefully considered for studies of communities such as carabid beetles, which have few strongly dominant species and a wide range of resource utilization.
Host selection and survival of the parasitoid Encarsia formosa on greenhouse whitefly, Trialeurodes vaporariorum, in the presence of hosts infected with the fungus Aschersonia aleyrodis
Authors: Fransen Joanne J. , van Lenteren Joop C. 
Published: April 2011

AbstractSuccessful control of greenhouse whitefly may be achieved by complementary activity of the parasitoid Encarsia formosa and the fungus Aschersonia aleyrodis. One way to obtain an additive mortality effect of both entomopathogen and parasitoid would be achieved by the selection of healthy hosts by the parasitoid and rejection of fungus‐infected hosts. Third and fourth instar larvae of Trialeurodes vaporariorum which had been treated with a spore suspension of A. aleyrodis 0, 4, 7, 10 or 14 days beforehand, were presented to female parasitoids. The parasitoids adopted the oviposition posture on untreated hosts as well as on treated hosts, irrespective of the different stages of infection in the hosts. However, significantly more hosts were parasitized by E. formosa in the control treatment than in the fungal treatment. The parasitoids offered treated hosts, showed rejection behaviour after probing on hosts showing detectable signs of infection (containing hyphal bodies or mycelium in the haemolymph). For instance, when hosts were offered seven days after spore treatment, the parasitoids showed an oviposition posture on a total of 83 (95.4%) out of 87 infected larvae, but laid only 4 eggs (4.6%). In contrast, on 48 (94.1%) out of 51 noninfected (or showing no detectable signs of infection) hosts an oviposition posture was adopted and 40 eggs (78.4%) were found after dissection. When infected hosts were encountered the oviposition posture lasted less than 1′40″ while rejection of non‐infected hosts occurred after more than 1′40″. Other experiments were carried out offering treated hosts for 24 h to the parasitoids. The hosts were dissected afterwards. Again, significantly more eggs were laid in the non‐infected hosts. When hosts were parasitized shortly after fungal spore treatment they were colonized by the fungus and the parasitoids did not develop. Transmission of the entomopathogen after probing infected hosts was observed to a limited extent. In conclusion, A. aleyrodis and E. formosa can be used together in a glasshouse situation. The parasitoid will be most effective when introduced more than seven days after application of A. aleyrodis, because from that time onwards it is able to detect and reject fungus‐infected hosts.
Further comments on analysis of covariance in insect dietary studies
Authors: Horton David R. , Redak Richard A. 
Published: April 2011

AbstractRaubenheimer & Simpson (1992) recently discussed the advantages of using analysis of covariance in insect dietary studies as an alternative to the more conventional ratio‐based nutritional indices. We expand on some interpretations of Raubenheimer & Simpson and illustrate our points with examples from published and unpublished data sets. Specifically, we show that an ANCOVA on biomass gain incorporating initial biomass as a covariate provides information not immediately available using the analysis suggested by Raubenheimer & Simpson (ANCOVA on final biomass incorporating initial biomass as a covariate). Second, we show that dietary studies in which the covariate (food consumption) is affected by diet can provide information about the relative importance of preingestive effects (e.g., deterrence) and postingestive effects (e.g., antibiosis) on performance. Cautions about this latter use of ANCOVA are discussed.