bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oviposition behavior of Coccidoxenoides peregrinus, a parasitoid of Planococcus ficus
Authors: Joyce A.L. , Hoddle M.S. , Bellows T.S. , González D. 
Published: October 2003

AbstractThe encyrtid parasitoid, Coccidoxenoides peregrinus has been used as a biological control agent against the mealybugs Planococcus citri and Planococcus ficus. This study examined the behavior and host selection of C. peregrinus attacking P. ficus. Adult parasitoids were fed a 0.1% solution of acridine orange, a DNA binding dye used to label C. peregrinus eggs. In a choice test, adult parasitoids were offered equal numbers of first through fourth instars of P. ficus and behavior of C. peregrinus was filmed and analyzed. Acridine orange labeled ova of the parasitoids found within mealybug hosts fluoresced green under fluorescence microscopy and presence of fluorescing eggs in hosts was used to determine oviposition events. A time budget prepared for C. peregrinus indicated that this parasitoid spent the majority of its time searching (71.64%) and grooming (15.06%). The average probing duration over all instars which led to oviposition from single visits was 4.93±0.62 s. A total of 35.51% of probes from all attacks led to ovipositions, whereas 33.72% of single visits to hosts resulted in ovipositions. Detection of fluorescing acridine orange labeled eggs showed all instars of P. ficus were acceptable for oviposition by C. peregrinus. There was a significant preference to probe second, third, and fourth instars rather than first instars of P. ficus. Host feeding was not observed for this parasitoid.
Insecticidal activity of avidin and streptavidin against four species of pest Lepidoptera
Authors: Markwick N.P. , Christeller J.T. , Dochterty L.C. , Lilley C.M. 
Published: October 2003

AbstractTwo biotin‐binding proteins, avidin and streptavidin, were found to be insecticidal to the larvae of four species of Lepidoptera – light brown apple moth, Epiphyas postvittana (Walker) (fam. Tortricidae), green‐headed leaf‐roller, Planotortrix octo (Dugdale) (fam. Tortricidae), brown‐headed leaf‐roller, Ctenopseustis obliquana (Walker) (fam. Tortricidae) and potato tuber moth, Phthorimaea operculella (Zeller) (fam. Gelechiidae). Mortality occurred in all species, but there was a wide range in susceptibility. P. operculella larvae were the most susceptible with an LC50 of respectively, 2.3 μg ml−1 for avidin and 1.4 μg ml−1 for streptavidin after 9 days. E. postvittana larvae had an LC50 of 43.4 μg ml−1 for avidin after 21 days, and C. obliquana larvae of 45.7 μg ml−1 for avidin after 28 days. Although significant mortality occurred in P.octo at the highest doses of avidin, there was no sufficient dose‐mortality response to calculate an LC50 for this species. For all species mortality curves were steep over a close range of doses followed by a plateau where mortality did not increase significantly with dose and did not reach 100%. Mortality was significantly affected by the amount of biotin in the diet on which the parental generation had been reared. Where this was rich in biotin, significant mortality of the offspring was much lower: larval offspring of a colony of E. postvittana, reared for five generations on a biotin‐free diet had an LC50 of 5.1 μg ml−1 after 14 days compared with 76.7 μg ml−1 for larvae from a colony reared on general purpose diet. The implications for use of these proteins to confer insect resistance on transgenic plants are discussed.
Economic injury levels for the scarabaeid Maladera matrida infesting peanut fields in Israel
Authors: Harari Ally Rachel , Ben‐Yakir David , Chen Michael , Rosen David 
Published: October 2003

AbstractControl of Maladera matrida Argaman (Coleoptera: Scarabaeidae) in peanut fields in the Negev region, Israel, relies on the ‘rule of thumb’ use of insecticides. The aim of this study was to develop an economic injury level (EIL) for a more judicious application of insecticides. Field studies were conducted from 1991 to 1993 to determine the relationship between the cumulative number of different immature stages and the damage of peanuts (Arachis hypogaea L.). Observed damage to peanut yield was found to relate best to second‐ and third‐instars (white grubs). This was supported by grub infestation experiments on potted peanut plants. Three different EIL levels for second‐ and third‐instars of M. matrida were established in connection with the peanut plant developmental stages as follows: an average of 13 grubs per soil sample (25 by 25 by 60 cm) taken during the first 3 weeks of nut development, of 4 grubs per soil sample during week 4 to 6, and of 1.5 grubs per soil sample from week 7 until harvest.
Determining numbers of active carabid beetles per unit area from pitfall‐trap data
Authors: Raworth David A. , Choi Man‐Young 
Published: October 2003

AbstractMovement of Pterostichus melanarius (Illiger) (Coleoptera: Carabidae) was studied in the laboratory, and a simulation model developed. The model was calibrated and validated using mark‐release‐recapture within a grid of pitfall traps in a commercial raspberry field. Rate of movement increased linearly with both temperature and starvation. The temperature threshold for movement, pooling all starvation levels was 3.8 °C ± 0.78 (s.e.). When beetles were released at various distances from a trap in the simulation model, the probability of capture during one day was about 0.13 at a release distance of 10 cm and fell rapidly with distance and temperature. At 5, 10, 15, and 20 °C, the maximum radius sampled by a trap in one day was about 8, 17, 24, and 29 m, respectively. Density was linearly related to catch, but the slope of the line and the variance of the density estimate increased rapidly at lower temperatures. Equations for determining density per m2 (±s.d.) were developed from the model, incorporating temperature, number of beetles caught per trap, and number of traps.
Larval feeding behavior of Dipel‐resistant and susceptible Ostrinia nubilalis on diet containing Bacillus thuringiensis (Dipel ES™)
Authors: Huang Fangneng , Buschman Lawrent L. , Higgins Randall A. 
Published: October 2003

AbstractDiet choice tests were conducted to examine the effects of Bacillus thuringiensis Berliner on larval feeding behavior of Dipel‐resistant and susceptible strains of European corn borer, Ostrinia nubilalis (Hübner). Larvae (first through fourth instars) were presented an untreated standard diet and three diets incorporating different concentrations of a commercial formulation of B. thuringiensis, Dipel ES™. Significantly higher proportions of susceptible and resistant larvae were found on the control diet compared to the proportions recorded on any of the Dipel‐treated diets. Soon after release (0.5 to 3 h), the occurrence of larvae on each of the diets was similar across different instars. The number of first and second instars on the control diet increased steadily over 72 h after release, when 43 to 75% of larvae were found on the control diet. The proportion of third and fourth instars on the control diet also increased initially, with an equilibrium occurring 12 to 24 h later when 30 to 40% of larvae were found on the control diet. Both strains appeared to avoid the Dipel‐treated diets and their responses were similar over different Dipel concentrations. The Dipel‐resistant strain showed higher ability to avoid the treated diets than the susceptible strain.
Influence of host log age and refuge from natural enemies on colonization and survival of Phoracantha semipunctata
Authors: Paine T.D. , Millar J.G. , Paine E.O. , Hanks L.M. 
Published: October 2003

AbstractThe eucalyptus longhorned borer Phoracantha semipuncata (F.) is native to Australia and has become established in most of the regions of the world where its Eucalyptus L'Heritier host trees have been introduced. To study the population dynamics of the insect in its native range, we investigated the influence of host log age (fresh or aged), protection from ant predation, and protection from parasitism by specialist larval parasitoids on numbers of initial larval feeding galleries, larval mortality, larval survivorship, and parasitization. There were greater numbers of initial larval galleries when ants were excluded, and greater numbers on fresh logs than on aged logs. However, mortality of larvae was greater in fresh logs, as well as when larvae were exposed to parasitism. Survivorship was greater when ants and parasitoids were excluded. Larvae achieved a larger size in fresh logs and in logs protected from parasitism. Fresh host material may provide a fitness advantage because it is a higher quality resource, but greater infestation of that material also increases the probability of mortality from competition among larvae. The results suggest that there are potential ecological interactions among food quality, host resistance, natural enemies, and competition that must be considered in evaluating the population dynamics of this species in native and novel environments.
Polyandry in field‐collected Spodoptera littoralis moths and laboratory assessment of the effects of male mating history
Authors: Sadek Medhat M. 
Published: October 2003

AbstractTo estimate multiple mating in females in the field, moths of S. littoralis were light‐trapped in June, July, August, and September in 1997 and 1998 in the edge of farming land in Assiut (Egypt). Females were dissected for the spermatophores in their bursae. Virgin females represented 8.04%, whereas once‐mated and multiply‐mated females were 37.2% and 54.76% of the trapped females, respectively. The average number of matings per trapped female (1.68±0.05) was significantly lower than that of laboratory‐reared females (2.48±0.11). As the number of captured males declined from June to September, there was a significant shift towards remating in the captured females. Laboratory mating experiments were performed with reared females that were daily supplied with males of different mating histories, including virgin males (V) or males that had previously mated once (PM1), twice (PM2), or three times (PM3). Females supplied with virgin males exhibited significantly lower numbers of matings acquired during a 5‐day experiment than females supplied with previously mated males. There was also a highly significant association between the frequency of mating among females and the mating history of males involved. Females supplied with previously mated males showed a higher propensity to remate than those supplied with virgin males. Significant increase of the reproductive capacity of females was associated with virginity (versus non‐virginity) of males or multiple mating (versus single mating) by females. Females paired with V or PM1 males exhibited shorter longevity and higher rates of egg laying than those paired with PM2 and PM3 males. The results suggest that females are able to assess the male mating status and, accordingly, alter their mating behavior to achieve higher reproductive capacity.
Pre‐ingestive and post‐ingestive effects of soya bean extracts and rutin on Trichoplusia ni growth
Authors: Hoffmann‐Campo C.B. , Harborne J.B. , McCaffery A.R. 
Published: October 2003

AbstractTotal ethanolic crude extracts from soya bean (Glycine max L. Merrill) PI 227687 and ‘Davis’, three purified fractions (A, B and C) from PI 227687, and pure rutin were tested for their effect on the growth of Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) larvae, from egg hatching to pupation. Analysis of covariance (ANCOVA), followed by bicoordinate utilisation plots, was used to remove the effect of feeding time from consumption and weight of pupae and to separate pre‐ ingestive and post‐ ingestive effects of different diets on T. ni growth. Survival, pupal weight, and feeding time of T. ni were all negatively affected by PI 227687 total extracts. Pupal weight and consumption remained affected by diet, after removing the effect of feeding time by ANCOVA. Larvae fed on the ‘Davis’ extract diet grew larger and consumed more rapidly a larger amount of food than those fed on PI 227687 and control diets. T. ni pupal weight was strongly influenced by consumption. In general, those insects that consumed more food were heavier but larvae fed on diet containing PI 227687 extract grew less than the others, irrespective of the amount of ingested and digested food. The feeding time was adversely affected by PI 227687 fraction A, composed of two flavonol glycosides (rutin and quercetin 3‐O‐glucosylgalactoside) and of an isoflavone glycoside (genistin). Survival and pupal weight were not affected, although the consumption and assimilation of ingested food was lower when larvae were fed on fractions A and C. The toxicity of the higher rutin concentration (2%) was similar to that observed when the insects were fed on unfractioned PI 227687, except that effects on food consumption were not observed. Results indicated that the feeding deterrence of PI 227687 must be caused by other compounds from fractions A and C. Moreover, rutin, acting as an antibiotic, appears to account for the adverse effects of PI 227687 on the physiology of T. ni.
Factors influencing the aggregative response of the blue willow beetle, Phratora vulgatissima
Authors: Peacock Lori , Lewis Mervyn , Herrick Sarah 
Published: October 2003

AbstractFactors influencing the aggregative response of the blue willow beetle, Phratora vulgatissima (L.) (Coleoptera: Chrysomelidae), on potted plants of Salix dasyclados (Wimm) were investigated in the field. A significantly higher female beetle density was recorded on plants that had a combination of beetle‐feeding damage and conspecific beetles present as compared with control plants and plants having only damage or beetles. Volatile chemicals emitted from undamaged S. dasyclados (Wimm) leaves were found to be benzaldehyde and the green leaf volatiles (GLVs) cis‐3‐hexenyl acetate and cis‐3‐hexenol. Upon beetle‐feeding damage, there was a higher concentration of these compounds and an increase in the number of different volatile chemicals emitted. These results are discussed in relation to the behavioural ecology of the willow beetle.
Effects of the aphid Rhopalosiphum padi on the leafhopper Psammotettix alienus under laboratory conditions
Authors: Alla S. , Moreau J.P. , Frérot B. 
Published: October 2003

AbstractThe aphid Rhopalosiphum padi (L.) coexists with the leafhopper Psammotettix alienus (Dahlbom) in the same cereal crops. However, dense populations of the aphid were never observed to be associated with dense populations of the leafhopper. This laboratory study focuses on the effect of the aphid at various densities on the development and reproductive biology of the leafhopper and constitutes a preliminary test to understand the interactions between these insects in the field.Independently of food quantity, an increase in aphid numbers caused a lengthening of development duration and increased mortality of leafhopper nymphs. In the absence of aphids, leafhopper nymphs preferred to feed on the lower part of the plant. In the presence of aphids, the leafhoppers moved towards the upper part of the plant. An increase in aphid numbers had no significant influence on the longevity of leafhopper females, although the daily fecundity decreased significantly. These data demonstrate the negative effect of R. padi on the development and fecundity of P. alienus and corroborated the field observations. Because food quantity was not the limiting factor, further experiments are underway to elucidate the factors modifying leafhopper biology. Such factors could be used to manipulate leafhopper populations.
Food consumption, utilization and detoxification enzyme activity of larvae of three polyphagous noctuid moth species when fed the botanical insecticide rotenone
Authors: Wheeler G.S. , Slansky F. , Yu S.J. 
Published: October 2003

AbstractWe assessed the effects of the isoflavonoid rotenone, an insecticidal allelochemical occurring in various legumes, on larval performance of three polyphagous noctuid species: the corn earworm (CEW), the fall armyworm (FAW) and the southern armyworm (SAW). As rotenone concentration was increased up to 1% fresh mass in an artificial diet, neither mortality (for all three species) nor food consumption (for SAW and FAW) was significantly affected, but developmental time of the latter two species was prolonged. In contrast, for CEW developmental time was shortened and food consumption declined, especially at the two highest rotenone concentrations. Final biomass of all three species declined as dietary rotenone increased.Analysis of covariance (ANCOVA) was used to evaluate larval food utilization analogous to, but without the potential statistical problems of, the traditional ratio‐based indices approximate digestibility (AD) and efficiency of conversion of digested food (ECD). Frass output, statistically adjusted to account for differences in consumption, increased with rotenone concentration for all three species, suggesting that, when ingested, this allelochemical interfered with the digestion and/or absorption of ingested food, especially at the higher concentrations tested.Significant statistical interactions in the ANCOVA necessitated the use of utilization plots to examine the linear regressions between biomass gain and absorption at each rotenone concentration. At the two highest concentrations, rotenone tended to reduce the amount of food absorbed by the larvae, as well as their ability to convert the absorbed food to biomass.When piperonyl butoxide, an inhibitor of the polysubstrate monooxygenase (PSMO) system known to metabolize rotenone, was added to the diet along with 0.5 or 1% rotenone, mortality increased significantly only for FAW, approaching or exceeding 50%. The only apparent effects of dietary rotenone on PSMO (aldrin epoxidase) activity (adjusted by ANCOVA for the covariate, crude homogenate protein) were for CEW, where activity decreased in all rotenone treatments compared to the control, and for SAW, where activity at the 3 lowest rotenone concentrations (0.001–0.1% fm) declined about 50% below that of larvae on the control diet, whereas at 0.5 and 1% rotenone, it increased approximately 2‐fold over that on the control diet.
Effects of a juvenile hormone analog, pyriproxyfen, on the apterous form of Lipaphis erysimi
Authors: Liu Tong‐Xian , Chen Tian‐Ye 
Published: October 2003

AbstractEffects of a juvenile hormone analog, pyriproxyfen, on various developmental stadia of the apterous form of the turnip aphid, Lipaphis erysimi (Kaltenbach), were bioassayed at three concentrations (50, 100, and 150 mg [AI]/l) in the laboratory. Supernumerary‐molted nymphs with 1‐3 extra molts were found when the first three nymphal instars were treated, and all these nymphs died prematurely. In contrast, all treated fourth instar nymphs molted normally to adults. The longevity of all pyriproxyfen‐treated L. erysimi nymphs and adults and the fecundity of treated adults were reduced by ≈50%. Higher concentrations of pyriproxyfen (100 and 150 mg [AI]/l) caused sterility in adults from treated fourth instars; whereas the lowest concentration (50 mg [AI]/l) did not cause any adult sterility. A majority of adults from treated fourth instars and treated adults produced normal nymphs, and some adults produced dead nymphs with normal appendages or dead and deformed nymphs without any appendages. Normal nymphs produced by the adults from treated adults or treated at fourth instars developed more slowly from first instar to adult than the water‐treated nymphs, and all adults in the new generation apparently reproduced normally. The potential role of pyriproxyfen in a vegetable aphid IPM program was discussed.
Geographic variability in diapause response of Japanese Orius species
Authors: Shimizu Toru , Kawasaki Kenjiro 
Published: October 2003

AbstractInterspecific and latitudinal variation in diapause characteristics were examined in 12 strains of Orius species (Heteroptera: Anthocoridae) including O. sauteri (Poppius), O. nagaii Yasunaga, O. minutus (L.), O. strigicollis (Poppius), and O. tantillus (Motschulsky) from Japan. A latitudinal cline was found in the photoperiodic response controlling reproductive diapause: the lower the latitude, the lower the diapause incidence and the shorter the critical daylength. To examine the overwintering success, eight strains including four species derived from different latitudes (26–43° N) were reared outdoors in Tsukuba (36° N), central Japan from the autumn of 1998 to the summer of 1999, and their winter survival and spring fecundity were recorded. Most females of the northern strains entered diapause in the autumn when the temperature was still high, and died before winter without oviposition. In the southern strains including a nondiapause Okinawa (26° N) strain of O. strigicollis, females overwintered as well as native strains in a state of quiescence. In all strains, the winter survival was significantly lower in males than in females, and eggs and nymphs failed to overwinter.
Orientation of Heterorhabditis megidis to insect hosts and plant roots in a Y‐tube sand olfactometer
Authors: Boff Mari I.C. , Zoon Frans C. , Smits Peter H. 
Published: October 2003

AbstractThe host‐searching behaviour of Heterorhabditis megidis strain NLH‐E 87.3 in the presence of insect hosts and plant roots, offered individually and in combination, was studied using a newly developed Y‐tube olfactometer filled with sand. Within a period of 24 hours infective juveniles (IJs) were significantly attracted to living G. mellonella larvae and caused 100% larval mortality. Otiorhynchus sulcatus larvae, however, did not elicit host‐oriented movement of IJs and no larval mortality was observed. Roots of strawberry plants induced a negative response in IJs. The combination of strawberry roots and O. sulcatus larvae, however, strongly attracted IJs leading to 37% host mortality. It was shown that this type of Y‐tube choice arena is a useful tool in studying the searching behaviour of entomopathogenic nematodes in a semi‐natural habitat.
A differential interaction study of Bemisia tabaci Q‐biotype on commercial tomato varieties with or without the Mi resistance gene, and comparative host responses with the B‐biotype
Authors: Nombela G. , Beitia F. , Muñiz M. 
Published: October 2003

AbstractThree tomato varieties (Motelle, Ronita, and VFN8) bearing the Mi‐1.2 gene providing resistance to nematodes Meloidogyne spp. and to the potato aphid Macrosiphum euphorbiae Thomas, and three varieties not bearing this gene (Moneymaker, Roma, and Río Fuego), were compared by choice assay for host preference using the Q‐biotype of Bemisia tabaci (Gennadius). The most preferred hosts, determined by infestation levels and numbers of feeding adults were Moneymaker, Río Fuego and Roma, all of which were not carrying the Mi gene. Ronita and Motelle, both of which bore the Mi gene, were the least preferred hosts. In a no‐choice assay, B. tabaci females laid a significantly lower number of eggs on the varieties that carried the Mi gene than on those lacking the gene. Differences were more dramatic when plants carrying the Mi gene were pooled together and compared with pooled plants without this gene. Significantly greater values were obtained for the Mi‐lacking group for all parameters tested. Comparing these results with those from a previous study on the B‐biotype of B. tabaci, Q‐biotypes were found to produce higher daily infestation rates on most of the tomato varieties. When results from plants carrying Mi were pooled, they showed lower infestation levels of Q‐biotypes than B‐biotypes. The Q‐biotype infested less Mi‐plants and more non‐Mi plants than B‐biotype. Q‐biotype females produced significantly less pupae than the B‐biotype females on both groups of plants. These results suggest the existence of an antixenosis and antibiosis‐based resistance to the Q‐biotype of B. tabaci in Mi‐bearing commercial tomato varieties, which is greater than that previously reported for the B‐biotype.