bluuebunny/crossref_metadata_2025_split huggingface dataset:
Induced resistance by Myzus persicae in the peach cultivar ‘Rubira’
Authors: Sauge Marie‐Hélène , Lacroze Jean‐Philippe , Poëssel Jean‐Luc , Pascal Thierry , Kervella Jocelyne 
Published: October 2003

AbstractThe effect of a previous infestation by the green peach aphid Myzus persicae (Sulzer) on the settling behaviour and reproduction of the same aphid species was investigated in the resistant peach cultivar Rubira, and compared with that observed in the susceptible control cultivar GF305. A previous infestation of 48 h triggered induced resistance in Rubira. There were significantly fewer aphids settling on preinfested than on uninfested plants, indicating an increased rejection of Rubira as a host plant. The level of induced resistance in preinfested plants was positively related to the duration of the first infestation. In GF305, previous infestation had no detrimental effect on aphid settlement and even slightly enhanced larviposition by adult females. The aphid probing behaviour after a 48‐h preinfestation was also monitored for 8 h with the electrical peneration graph (EPG) technique. On preinfested GF305, most EPG parameters indicated an enhanced host plant acceptance. On preinfested GF305, aphids produced less sieve element salivation and more continuous sap ingestion than on uninfested GF305, indicating that the previous aphids provoked changes in plant properties beneficial to the test aphids. In Rubira, a major induced factor of resistance was thought to be expressed in the sieve element as phloem sap ingestion was 4‐fold shorter on preinfested than on uninfested plants. The time taken by the aphid stylets to reach a sieve element was also significantly increased on preinfested Rubira, suggesting the induction of resistance factors outside the phloem. The originality of the Rubira/M. persicae interaction is discussed in the perspective of a better understanding of plant induced responses to aphids.
Stylet penetration behavior resulting in inoculation of a semipersistently transmitted closterovirus by the whitefly Bemisia argentifolii
Authors: Johnson D.D. , Walker G.P. , Creamer R. 
Published: October 2003

AbstractThe electrical penetration graph (EPG) technique was used to determine what part of stylet penetration behavior by the whitefly vector, Bemisia argentifolii Bellows & Perring (Homoptera: Aleyrodidae), is lettuce chlorosis virus (LCV) inoculated in the host plant Malva parviflora L. LCV is a semipersistently‐transmitted closterovirus. Since closteroviruses generally are found in the phloem of their plant hosts, this study tested the hypothesis that virus inoculation occurs during the phloem phase of stylet penetration behavior. Virus‐exposed whiteflies were allowed to feed on uninfected host plants, and the whiteflies were divided into two experimental groups: group 1 attained phloem phase on the uninfected plants, and group 2 did not attain phloem phase. Two series of tests were conducted, one where whiteflies were manipulated so that the amount of time spent in non‐phloem phase stylet penetration behaviors was similar between group 1 and group 2, and a second series of tests where whiteflies were manipulated so that the number of intracellular punctures made during stylet penetration was similar between group 1 and group 2. Both series of tests indicated that virus inoculation took place primarily during phloem phase. Considering only individual whiteflies shown to be capable of transmitting virus, 11 of 23 whiteflies (48%) in the phloem phase treatment successfully inoculated the virus whereas only one of 19 whiteflies (5%) in the non‐phloem phase treatment successfully inoculated the virus (P= 0.00008).
A rapid hypersensitive response associated with resistance in the willow Salix viminalis against the gall midge Dasineura marginemtorquens
Authors: Ollerstam Olof , Rohfritsch Odette , Höglund Solveig , Larsson Stig 
Published: October 2003

AbstractGreat genotypic variation in resistance against the gall midge Dasineura marginemtorquens Bremi (Diptera: Cecidomyiidae) exists within its willow host Salix viminalis L. (Salicaceae). In some resistant genotypes larvae die within 40 h after attempting to initiate galls. The present study tested the hypothesis that the hypersensitive response (HR) is involved in incompatible interactions between D. marginemtorquens and S. viminalis. By means of UV/blue light and visible light microscopy, we verified a rapidly (within 12 h after egg hatch) spreading cell death of an HR‐type due to larval attack in resistant willow genotypes. Twelve h after egg hatch, the cell death had spread up to six cell layers in resistant S. viminalis genotypes whereas in susceptible genotypes only up to two cell layers were affected. In the groups of dead cells on the resistant genotypes accumulation of phenolics was observed within 24 h after egg hatch. The rapidity of the cell death induction, the early local accumulation of phenolic compounds, and the strong association of the cell death with larval mortality suggest that the formation of dead cells in resistant willow genotypes should be interpreted as a true HR.
Attraction and feeding responses of Mediterranean fruit fly and a natural enemy to protein baits laced with two novel toxins, phloxine B and spinosada
Authors: Vargas Roger I. , Miller Neil W. , Prokopy Ronald J. 
Published: October 2003

AbstractStudies were conducted to determine attraction and feeding propensity of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), to different protein bait mixtures with and without the insecticides malathion, spinosad, and phloxine B. Protein baits were more attractive to females than to males. Protein‐starved females responded more than protein‐fed females. The type of protein (USB® yeast hydrolysate enzymatic, Mazoferm®E802, Nu‐Lure®Insect Bait, or Provesta® 621 autolyzed yeast extract) in the bait had a major influence on C. capitata attraction, which was strongest to fresh Provesta. Aged baits (four day‐old) were not as attractive as fresh baits. In feeding propensity studies, highest response was observed for USB protein. On the basis of attraction and feeding responses Provesta (attraction and feeding) and USB (feeding) outperformed the standard Nu‐Lure. Protein‐starved flies were much more likely to feed on protein compared to protein‐fed flies. For protein‐starved flies, a mixture of Provesta and malathion repelled fruit flies, compared to a mixture of Provesta and spinosad or phloxine B. This was not the case with protein–fed flies. The wasp Fopius arisanus (Sonan), one of C. capitata's primary natural enemies in Hawaii, would not consume protein baits. Our studies suggest that spinosad or phloxine B, with low contact toxicity, mixed with protein baits offers a more environmentally friendly choice for control of C. capitata and conservation of F. arisanus, whereby the nontarget effects of broad spectrum contact poisons such as malathion can be avoided. Presumably, due to greater selectivity with spinosad and phloxine B bait treatments, the host would be killed, but not the natural enemy.
Interaction between insect strain and artificial diet in diamondback moth development and reproduction
Authors: Carpenter James E. , Bloem Stephanie 
Published: October 2003

AbstractThe economical production of physiologically and behaviorally competent diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae), is critical to most research and control programs against this insect. Although a few laboratory‐adapted colonies are currently maintained on artificial diets, the establishment and adaptation of feral DBM onto semi‐synthetic diets is often difficult. Understanding the interactions between insect strain and diet may be critical to the process of laboratory adaptation as well as to the successful use of laboratory‐reared insects in the field. As such, the objective of this study was to investigate the interaction between several DBM colonies/strains and different natural and semi‐synthetic diets. Specifically, we examined the effect of different diets on the length of development, percent survival, adult weight, female fecundity, and adult longevity for two feral and one laboratory‐adapted strain of DBM. Significant interactions were observed between diet and laboratory‐adapted and feral strains, and also between diet and different feral strains with respect to many of the growth and development parameters tested. Therefore, the performance of one strain of DBM on a particular diet was not necessarily predicted by the performance of another DBM strain on the same diet. However, the soy‐based diet developed and reported herein performed well for all three DBM strains tested. In future efforts to colonize feral DBM, we suggest that researchers assay different diet formulations in order to identify a semi‐synthetic diet that is most suitable for the particular DBM strain under consideration.
Kairomones from scarabaeid grubs and their frass as cues in below‐ground host location by the parasitoids Tiphia vernalis and Tiphia pygidialis
Authors: Rogers Michael E. , Potter Daniel A. 
Published: October 2003

AbstractCues used in below‐ground host‐searching behaviour and host discrimination were examined for Tiphia vernalis Rohwer and Tiphia pygidialis Allen (Hymenoptera: Tiphiidae), ecto‐parasitoids of root‐feeding larvae of the Japanese beetle, Popillia japonica Newman, and masked chafers, Cyclocephala spp. (Coleoptera: Scarabaeidae), respectively. Response to potential stimuli was compared in dual choice tests in an observation chamber filled with soil. Each wasp showed species‐specific, directed movement along residual body odor trails made by dragging its respective host through the soil. Presence of a grub was not necessary for wasps to follow such trails. Frass from either host‐ or non‐host grubs elicited trail‐following, but each Tiphia species followed frass trails from its respective host when a choice was presented. Frass trails elicited stronger responses than body odor trails. The combination of host frass and body odor elicited the strongest trail‐following responses. Our results suggest that once in the soil, Tiphia spp. locate their hosts using contact kairomones present in grub body odor trails and frass.
Biological differences in reproductive strategy between the mosquito sibling species Anopheles gambiae sensu stricto and An. quadriannulatus
Authors: Takken Willem , Stuke Kristin , Klowden Marc J. 
Published: October 2003

AbstractFemales of the afrotropical mosquito species Anopheles gambiae Giles sensu stricto and An. quadriannulatus (Theobald) (Diptera: Culicidae) were studied for the effect of blood meal size and the frequency of blood feeding on reproductive development during the first gonotrophic cycle. To standardize the blood meals, meals were administered by enema in some experiments. The effects of insemination, mosquito size, and metabolic reserves at emergence on egg development were also investigated. Maximum insemination was reached after seven days, varying from 62% in An. quadriannulatus to 95% in An. gambiae and was significantly different (P<0.05) between the two species. Insemination had no effect on feeding success. Females of An. quadriannulatus were significantly larger than An. gambiae females (mean wing size 2.90 ±0.01 mm versus 2.82 ±0.01 mm), but the protein, glycogen, and lipid content of newly emerged females of the two species were not significantly different. Without a blood meal, larger females of both species were significantly more likely to develop oocytes up to Christopher's stage II. With one blood meal, 27% of An. gambiae became pre‐gravid and 73% matured eggs. In contrast, all An. quadriannulatus females remained in the pre‐gravid stage following ingestion of one blood meal. Vitellogenesis was significantly reduced in smaller‐sized pre‐gravid An. quadriannulatus compared to larger individuals. When given the opportunity to feed up to three times on three successive days, all females of An. gambiae matured eggs but only 85% of An. quadriannulatus did so. When 1 μl of human blood was administered by enema, none of the females of either species developed eggs. With a single enema of 1.5 μl of human blood, only An. gambiae developed eggs. A similar result was observed with 1 μl and 1.5 μl enemas of bovine blood although some An. gambiae also developed eggs with 1 μl of blood. Anopheles quadriannulatus developed eggs only when given two 1 μl enemas on successive days. However, the percentage of females developing eggs was significantly lower than that of An. gambiae. The implications of these differences in reproductive strategy are discussed in the light of behavioural traits in the field.
Foliar pubescence and resistance to potato moth, Phthorimaea operculella, in Lycopersicon hirsutum
Authors: Gurr G.M. , McGrath D. 
Published: October 2003

AbstractPubescence characteristics for six accessions of Lycopersicon hirsutum Dunal and five accessions of L. hirsutum f. glabratum CH Mull. were determined and compared with those of an accession of cultivated tomato (L. esculentum Mill.). Removal of trichome exudates from excised leaflets using ethanol solution resulted in a reduced mortality and increased survival of potato moth (Phthorimaea operculella (Zeller)) neonates for the accessions that were most lethal when not treated with ethanol solution. No such treatment effect was evident for L. esculentum or for the L. hirsutum accession with least effect on neonates when its trichomes were intact. In a glasshouse experiment with caged intact plants, mortality of neonate P. operculella placed on the abaxial surface was greater on seven accessions than for L. esculentum. Neonates were less severely affected on the adaxial surface. Eleven days after inoculation, no live larvae were found on LA 1927, PI 127827, PI 134418, and PI 134428, and numbers on other accessions were lower than for L. esculentum. Eventual emergence of adults followed a similar trend. Multiple regression of insect data against pubescence indicated a significant correlation between density of type IV and VI trichomes and neonate mortality, decreased larval development and decreased adult emergence. Non‐glandular type V trichomes were positively correlated with high survival of insects to 11 days and to adult. Though factors other than glandular trichomes are likely to be important, increased density of type IV and VI, along with reduced type V, are shown to be important to select in breeding for P. operculella resistance.
Effect of differential host exposure on reproduction in the solitary ectoparasitoid Eupelmus vuilleti
Authors: Darrouzet Eric , Huignard Jacques , Chevrier Claude 
Published: October 2003

AbstractWe examined self‐superparasitism in Eupelmus vuilleti (CRW.), a solitary ectoparasitoid of larvae of Callosobruchus maculatus (F.) which develop in cowpea seeds. The reproduction of isolated females was analysed in the presence of seeds containing 10 or 30 hosts for 24, 48, and 72 h. At the two host densities, female reproductive activity increased with host exposure time, but variations in offspring number per female were limited. The propensity of the females to self‐superparasitise their hosts after long exposure times could explain these results. The offspring sex ratio was female biased but tended to 0.5 for longer exposure times. The absence of host renewal for a 3‐day period was followed by an increase in self‐superparasitism which reduced the parasitoid survival rate and by emergence of a lower number of females in the offspring. The offspring production was then analysed when females were provided with ten hosts a day or with 30 hosts every three days throughout their life span. The reduction of host renewal frequency did not affect male production but caused a reduction in the number of females emerging from the seeds. The importance of a high rate of self‐superparasitism on the population biology of this parasitoid is discussed.
Effects of hunger level and nutrient balance on survival and acetylcholinesterase activity of dimethoate exposed wolf spiders
Authors: Pedersen Lars‐Flemming , Dall Lars G. , Sørensen Bo C. , Mayntz David , Toft Søren 
Published: October 2003

AbstractThe influence of two nutritional factors (food quantity and quality) on the responses of a wolf spider, Pardosa prativaga (L.K.), to a high dose of the insecticide dimethoate, was investigated in a fully factorial experimental design. Spider groups with different (good and bad) nutrient balance were created by feeding them fruit flies of either high or low nutrient content for 28 days. Both groups were then split into satiated and 14 days starved subgroups. Each of these was further divided into insecticide treated and control halves. Survivorship and acetylcholinesterase (AChE) activity measured on the survivors were used as response variables. Survivorship after topical dimethoate exposure (LD50; 48 h) was influenced by spider body weight, nutrient balance, and starvation. Furthermore, AChE activity was significantly inhibited by dimethoate exposure. A significant interaction between nutrient balance, starvation, and dimethoate exposure revealed synergistic effects of starvation and nutrient imbalance on AChE inhibition by dimethoate in surviving spiders. These results show that the tolerance of non‐target arthropods to dimethoate may vary depending on the nutritional history of the animal.
Effects of sub‐lethal imidacloprid levels on potato leafroll virus transmission by Myzus persicae
Authors: Mowry Thomas M. , Ophus John D. 
Published: October 2003

AbstractThe effects of sub‐lethal imidacloprid concentrations on acquisition and inoculation of potato leafroll virus (PLRV) by Myzus persicae (Sulzer) (Hemiptera: Aphididae) were investigated. In experiments using two aphid clones to acquire PLRV from infected potatoes, virus transmission declined significantly with increasing concentrations of imidacloprid. The same was true in experiments using imidacloprid‐treated Physalis floridana Rydb. as acquisition sources. When viruliferous M. persicae were placed on uninfected, imidacloprid‐treated P. floridana, there were significant declines in PLRV transmission. Sub‐lethal concentrations of imidacloprid clearly inhibited both acquisition and inoculation of PLRV by M. persicae, either through poisoning, temporary intoxication, and/or antifeedant effects.
The role of sinigrin in host plant recognition by aphids during initial plant penetration
Authors: Gabrys B. , Tjallingii W.F. 
Published: October 2003

AbstractPlant penetration behaviour (probing) of the cabbage aphid, Brevicoryne brassicae, and the pea aphid, Acyrthosiphon pisum, was studied on excised leaves of broad beans, Vicia faba, kept in water or in a 1% aqueous solution of sinigrin. Using the DC EPG (Electrical Penetration Graph) technique it was shown that the cabbage aphid on sinigrin‐untreated bean leaves showed numerous short probes into epidermis and mesophyll. None of these aphids showed either phloem salivation or ingestion waveforms on untreated leaves. In contrast, on sinigrin‐treated bean leaves, 35% of the probing time was spent on phloem sap ingestion (E2) and almost all aphids reached phloem vessels and started feeding. The duration of phloem salivation before phloem ingestion and the mean duration of phloem ingestion periods were similar on a host and a sinigrin‐treated non‐host plant. However, the total probing time by B. brassicae was 10% longer, the total phloem sap ingestion time was twice as long, and the time to the first phloem phase within a probe was three times shorter on the host plant compared to sinigrin‐treated broad beans. Acyrthosiphon pisum also responded to the addition of sinigrin to broad beans, but in this case sinigrin acted as a deterrent. On sinigrin‐treated leaves, A. pisum terminated probes before ingestion from phloem vessels, and none of these aphids showed phloem salivation and ingestion on treated leaves. Glucosinolates were detected in the mesophyll cells of the brassicaceous plant, Sinapis alba. Based on this finding and in addition to the foregoing EPG analysis of aphid probing on these plants and broad beans, our hypothesis is that aphids may recognise their host plants as soon as they probe the mesophyll tissue and before they start ingestion from phloem vessels.
Performance of pine looper Bupalus piniarius larvae under population build‐up conditions
Authors: Šmits Agnis 
Published: October 2003

AbstractIn the first year of an outbreak, Bupalus piniarius larvae, encounter intense crowding. In the later stages of larval development, they are forced to feed on the non‐preferred current‐year needles of Scots pine or even on alternative hosts. It was hypothesized that larval feeding on a non‐preferred resource (current‐year needles) will negatively affect B. piniarius performance. It was also hypothesized that larval mutual interference (crowding without competition for food) will have negative additive effects. These hypotheses were tested in laboratory and field experiments. Fourth instar larvae were reared singly and under crowded conditions in cohorts of ten. Larvae in both situations were reared on control branches (containing both mature and current‐year shoots) and branches containing only current‐year shoots. Crowded larvae were reared also on Norway spruce, an alternative host. Crowding and feeding on a non‐preferred resource had opposite effects on B. piniarius larval performance. Crowding in the late larval instars enhanced larval performance while absence of the preferred resource had negative effects. Larval growth rate was higher and development time was shorter for larvae exposed to crowded conditions than for solitary larvae. There was, however, no difference between the groups in final pupal weights or survival. Survival was 25% lower for larvae feeding on non‐preferred current‐year needles and pupal weights 9% lower, compared with results for larvae feeding on mature needles. Larvae feeding on Norway spruce suffered greatly extended development time, 82% lower survival, and resulted in 60% lighter pupae compared with conspecifics on Scots pine. It was concluded that not only quantity but also quality of the available food resource is critical for B. piniarius development.
Aphid response to elevated ozone and CO2
Authors: Holopainen Jarmo K. 
Published: October 2003

AbstractNumerous reports indicate that pollution stress caused by sulphur dioxide (SO2), oxies of nitrogen or fluorides promote aphid growth on herbaceous and woody plants. At SO2 exposures, the response curve of aphids is bell‐shaped having the peak at 100 ppb. This curvilinear response is related to physiological stress responses of host plants exposed to pollutants. On the other hand, observations of aphid performance on ozone‐exposed (O3) or elevated carbon dioxide‐exposed (CO2) plants have given very variable results. Depending on the duration and concentration of O3 or elevated CO2 exposure or the age of the exposed plants, aphid growth on the same plants either decreased or increased in comparison to growth on control plants grown in filtered air. The results of these studies suggest that there is no general air pollution‐induced plant stress that triggers aphid outbreaks on plants. Plants grown in elevated CO2 usually have higher C/N ratios than plants grown in current ambient CO2 atmosphere. A reduced proportion of nitrogen in the plant foliage decreases growth of chewing herbivorous insects, but the few studies of elevated CO2 effects on sucking insects such as aphids have not yielded similar consistent effects. The present paper reviews recent studies of elevated CO2 effects on aphids and discusses the effects of combined elevated O3 and CO2 exposures on aphid performance on woody plants using pine and birch aphids as examples.