| intra- and interspecific interactions between lysiphlebus testaceipes and lipolexis scutellaris (hymenoptera: aphidiidae) reared on toxoptera citricida (homoptera: aphididae). | classical biological control of the brown citrus aphid toxoptera citricida kirkaldy in florida has involved the release of lipolexis scutellaris mackauer. lysiphlebus testaceipes cresson is already present in florida and also parasitizes t. citricida. because parasitoid-parasitoid interactions may affect the establishment of a newly introduced parasitoid species, intra- and interspecific larval interactions of both parasitoids were studied in the laboratory using t. citricida reared on citrus. f ... | 2003 | 12852589 |
| sucrose octanoate toxicity to brown citrus aphid (homoptera: aphididae) and the parasitoid lysiphlebus testaceipes (hymenoptera: aphidiidae). | we report the toxicological effects of a new biorational, synthetic sucrose octanoate (ava chemical ventures l.l.c., portsmouth, nh), on brown citrus aphid, toxoptera citricida (kirkaldy), nymphs and adults and to its native parasitoid lysiphlebus testaceipes (cresson). sucrose octanoate topically applied was equally toxic to brown citrus aphid adults and nymphs with lc50 and lc90 values ranging from 356 to 514 and 1029 to 1420 ppm, respectively. mortalities of both stages did not differ signifi ... | 2004 | 15384331 |
| tritrophic interaction of parasitoid lysiphlebus testaceipes (hymenoptera: aphidiidae), greenbug, schizaphis graminum (homoptera: aphididae), and greenbug-resistant sorghum hybrids. | interactions of the parasitoid lysiphlebus testaceipes (cresson) and the greenbug, schizaphis graminum (rondani), on greenbug-resistant 'cargill 607e' (antibiosis), 'cargill 797' (primarily tolerance), and -susceptible 'golden harvest 510b' sorghum, sorghum bicolor (l.) moench, were tested using three levels of biotype i greenbug infestation. the parasitoid infestation rate was 0.5 female and 1.0 male l. testaceipes per plant. for all three greenbug infestation levels, the parasitoid brought the ... | 2005 | 15765684 |
| estimation of hymenopteran parasitism in cereal aphids by using molecular markers. | polymerase chain reaction (pcr) primers were designed and tested for identification of immature parasitoids in small grain cereal aphids and for estimation of parasitism rates. pcr technique was evaluated for 1) greenhouse-reared greenbugs, schizaphis graminum (rondani), parasitized by lysiphlebus testaceipes cresson and 2) aphids collected from winter wheat fields in caddo county, oklahoma. for greenhouse samples, parasitism frequencies for greenbugs examined by pcr at 0, 24, and 48 h after rem ... | 2005 | 15765686 |
| toxicity of fruit fly baits to beneficial insects in citrus. | two fruit fly baits, nu-lure/malathion and gf-120 (spinosad) were evaluated in the laboratory for non-target impacts on beneficial insects. nu-lure/malathion proved attractive and toxic to adults and larvae of the coccinellid species, curinus coeruleus mulsant, cycloneda sanguinea l. and harmonia axyridis pallas, a lacewing species, chrysoperla rufilabris burmeister. the coccinellids olla v-nigrum mulsant, scymnus sp. and nymphs of the insidious flower bug, orius insidiosus (say) did not succumb ... | 2003 | 15841224 |
| phylogenetic and structural relationships of the pr5 gene family reveal an ancient multigene family conserved in plants and select animal taxa. | pathogenesis-related group 5 (pr5) plant proteins include thaumatin, osmotin, and related proteins, many of which have antimicrobial activity. the recent discovery of pr5-like (pr5-l) sequences in nematodes and insects raises questions about their evolutionary relationships. using complete plant genome data and discovery of multiple insect pr5-l sequences, phylogenetic comparisons among plants and animals were performed. all pr5/pr5-l protein sequences were mined from genome data of a member of ... | 2006 | 16736102 |
| [occurrence of lysiphlebus testaceipes (cresson) (hymenoptera: aphidiidae) on aphids (hemiptera: aphididae) in wheat plantation in medianeira, parana state, brazil]. | this paper records the occurrence of lysiphlebus testaceipes (cresson) attacking aphids in wheat plantation in medianeira, in the west region of paraná state, brazil. this microhymenoptera was introduced and released by embrapa trigo, from 1978 to 1992 in the wheat production region at the state of rio grande do sul, what suggests that individuals of this species may show high dispersal ability. | 2006 | 17348143 |
| parasitism of greenbug, schizaphis graminum, by the parasitoid lysiphlebus testaceipes at winter temperatures. | functional responses by lysiphlebus testaceipes (cresson), a common parasitoid of small grain aphids, on greenbug, schizaphis graminum (rondani), were measured at seven temperatures (14, 12, 10, 8, 6, 4, and 2 degrees c) during a 24-h period (12-h light: 12-h dark). oviposition by l. testaceipes ceased at temperatures <4 degrees c. at all experimental temperatures, a type i, rather than a type ii or type iii, functional response was determined to be the best fit based on coefficient of determina ... | 2007 | 17349109 |
| suppression of soybean aphid by generalist predators results in a trophic cascade in soybeans. | top-down regulation of herbivores in terrestrial ecosystems is pervasive and can lead to trophic cascades that release plants from herbivory. due to their relatively simplified food webs, agroecosystems may be particularly prone to trophic cascades, a rationale that underlies biological control. however, theoretical and empirical studies show that, within multiple enemy assemblages, intraguild predation (igp) may lead to a disruption of top-down control by predators. we conducted a factorial fie ... | 2007 | 17489251 |
| an implicit approach to model plant infestation by insect pests. | various spatial approaches were developed to study the effect of spatial heterogeneities on population dynamics. we present in this paper a flux-based model to describe an aphid-parasitoid system in a closed and spatially structured environment, i.e. a greenhouse. derived from previous work and adapted to host-parasitoid interactions, our model represents the level of plant infestation as a continuous variable corresponding to the number of plants bearing a given density of pests at a given time ... | 2007 | 17582442 |
| molecular analysis of predation on parasitized hosts. | predation on parasitized hosts can significantly affect natural enemy communities, and such intraguild predation may indirectly affect control of herbivore populations. however, the methodological challenges for studying these often complex trophic interactions are formidable. here, we evaluate a dna-based approach to track parasitism and predation on parasitized hosts in model herbivore-parasitoid-predator systems. using singleplex polymerase chain reaction (sp-pcr) to target mtdna of the paras ... | 2008 | 18439340 |
| virgins in the wild: mating status affects the behavior of a parasitoid foraging in the field. | in haplodiploid organisms, virgin females can produce offspring, albeit only sons. they may therefore face a trade-off between either: (1) searching for hosts and producing sons immediately; or (2) searching for mates and perhaps producing both sons and daughters later in life. although this trade-off raises a theoretical interest, it has not been approached experimentally. the objective of this article is thus to document the effect of mating status on the foraging behavior of a haplodiploid pa ... | 2008 | 18446375 |
| seasonal abundance of resident parasitoids and predatory flies and corresponding soybean aphid densities, with comments on classical biological control of soybean aphid in the midwest. | seasonal abundance of resident parasitoids and predatory flies, and corresponding soybean aphid, aphis glycines matsumura (hemiptera: aphididae), densities were assessed in soybean fields from 2003 to 2006 at two locations in lower michigan. six parasitoid and nine predatory fly species were detected in 4 yr by using potted plants infested with soybean aphid placed in soybean fields. the parasitoid lysiphlebus testaceipes cresson (hymenoptera: braconidae) and the predatory flies aphidoletes aphi ... | 2008 | 18459389 |
| [quality of different aphids as hosts of the parasitoid lysiphlebus testaceipes (cresson) (hymenoptera: braconidae, aphidiinae)]. | lysiphlebus testaceipes (cresson) has a broad aphid host range; however the quality of these preys may interfere in its biological feature. this study aimed to evaluate the quality of three macrosiphini, brevicoryne brassicae (l.), lipaphis erysimi (kaltenbach) and myzus persicae (sulzer), and three aphidini schizaphis graminum (rondani) rhopalosiphum maidis (fitch) and aphis gossypii glover as hosts to l. testaceipes and to determine the relation possible of host preference, of size and quality ... | 2008 | 18506297 |
| [development and parasitism of lysiphlebus testaceipes (cresson) and aphidius colemani viereck (hymenoptera: braconidae) on aphis gossypii glover (hemiptera: aphididae) on two chrysanthemum cultivars]. | the parasitoids lysiphlebus testaceipes (cresson) and aphidius colemani viereck play an important role on the regulation of aphid populations on chrysanthemum grown in greenhouses. this study evaluated the interaction of biological control and plant resistance by the development and the parasitism of l. testaceipes and a. colemani on aphis gossypii glover. the aphid host was kept on commercial cultivars of chrysanthemum susceptible yellow snowdon (ys) and resistant white reagan (wr). the experim ... | 2006 | 18575697 |
| supercooling points of lysiphlebus testaceipes and its host schizaphis graminum. | supercooling points (scps) were measured for various life stages of male and female lysiphlebus testaceipes (cresson) parasitoids, along with mummies and its aphid host, schizaphis graminum (rondani). some parasitoids were acclimated (4 h at 10 degrees c before cooling down to the scp) to determine whether this could significantly lower the scp. acclimation did not improve scps for l. testaceipes. an inverse relationship between age of the adult parasitoid and its scp was detected. nonacclimated ... | 2008 | 19036182 |
| habitat affinity of resident natural enemies of the invasive aphis glycines (hemiptera: aphididae), on soybean, with comments on biological control. | we integrated a natural enemy survey of the broader landscape into a more traditional survey for aphis glycines matsumura (hemiptera: aphididae), parasitoids and predatory flies on soybean using a. glycines-infested soybean, glycine max (l.) merr., placed in cropped and noncropped plant systems to complement visual field observations. across three sites and 5 yr, 18 parasitoids and predatory flies in total (hymenoptera: aphelinidae [two species] and bracondae [seven species], diptera: cecidomyii ... | 2010 | 20568602 |