[学术文献] Natural insecticidal proteins, the promising bio-control compounds for future crop protection 进入全文
Insect predation problem in agriculture and forestry has challenged researchers worldwide to identify newer eco-friendly insecticides. Among them Bacillus thuringiensis δ-endotoxin (Bt) has been the most widely used commercial insecticide till date. The advantages of Bt as a “green” insecticide are its high specificity to target insects (it is nontoxic to mammals, birds and even to most beneficial insects) and the slow rate of development of resistance against it by insects. This toxin used either in the form of bio formulations or through its expression in crop plants, is found to be sensitive against insect pests belonging to the family Lepidoptera, Coleoptera and Diptera. However, the sap sucking homopteran group of insects generally remain insensitive to Bt toxin and show susceptibility to various plant lectins when fed with artificial diet or through expression in transgenic plants. This review demonstrates the insecticidal potential of some candidate proteins and their possible mode of action by identifying their target molecules in insects’ tissue. We also provide an overview of the applicability of these proteins in crop protection.
[学术文献] A simplified method for monitoring eggs of the grape leafhopper (Empoasca vitis) in grapevine leaves 进入全文
Journal of Plant Diseases & Protection 期刊
Based on a previously reported method for monitoring eggs of the grape leafhopper (BÖLL and HERRMANN 2001) stated as Leda (Leafhopper Egg Detection by Autofluorescence), a simplified but equally reliable version of this method, Sleda (Simplified Leafhopper Egg Detection by Autofluorescence), is introduced. Both methods are based on the fact that the leafhopper eggs show an intense green autofluorescence under blue light excitation. However, in contrast to Leda, for Sleda a fluorescent light microscope is no longer prerequisite, only an optic light source equipped with a blue exciter and a commercial blue cutter are required.
[学术文献] Ovipositional Stimulus Deprivation and its Effect on Lifetime Fecundity of Delia antiqua (Meigen) (Diptera: Anthomyiidae) 进入全文
Environmental Entomology 期刊
Lifetime oviposition was measured for female Delia antiqua (Meigen) caged individually with cups of moist sand or surrogate onions possessing combinations of host-plant color and chemical stimuli. Females laid more eggs on surrogates than on sand and laid more eggs on surrogates coated with synthetic onion volatiles ( n -dipropyl disulfide, Pr2S2 )than on untreated surrogates. Surrogate color had no effect on fecundity. Flies deprived of exposure to Pr2S2 took longer to initiate oviposition and took longer to complete ovipositional cycles. The presence of untreated surrogates increased the percentage of eggs laid in ovipositional cups from 14 to 74%, whereas the presence of Pr2S2 or host-plant color resulted in nearly all eggs being laid in cups. The number of eggs retained at death did not differ among treatments. The results suggest that differential oviposition may have resulted from reduced rates of egg maturation as a consequence of accumulation of unlaid eggs. Host specialization by the onion fly is probably due to ecological factors as well as an ovipositional preference for onion.
[学术文献] Low conservatism of leafhopper communities in remnant and reconstructed prairie sites in a working agroecological landscape 进入全文
Journal of Insect Conservation 期刊
Leafhoppers (Hemiptera: Cicadellidae) form a large, diverse insect family that contributes significantly to trophic interactions and pathogen transmission in grasslands. We compared leafhopper communities of five remnant prairies and five prairie reconstructions in northeastern Kansas, USA. We hypothesized that leafhopper communities would be more conservative (i.e., greater dependence on prairies) and diverse on remnant as compared to reconstructed prairies, and that remnants would support more grass-feeders. We also predicted that sites surrounded by natural/semi-natural landscapes would have greater leafhopper diversity. We found grass feeders represented a higher proportion of leafhoppers on remnants. We found, however, no difference in mean conservatism between remnants and reconstructions, and overall levels of conservatism were lower than other grassland data sets. Mean conservatism was greater in the mid-summer than in early summer, where migratory pests such as Macrosteles were abundant. Although remnants and reconstructed prairies didn’t differ in leafhopper diversity, diversity increased with forb percent cover. The amount of natural and semi-natural land cover around sites had complex relationships with leafhopper diversity and composition. For future studies, we encourage coordinated studies on leafhopper communities across the tallgrass prairie region, with a particular focus on conservatism. Deciphering the effect of survey times, and grassland size and management, on prairie-dependent leafhoppers is important. We predict that large numbers of migratory species may lead to greater homogeneity in leafhopper communities across sites early in the season. Over time, site types and landscape features may progressively filter species and amplify local specialists, resulting in more late-season variation among sites.
Provided is a water dispersion type sex pheromone sustained release preparation which makes it possible to suppress excess release at the initial stage of spraying and release a sex pheromone substance at a constant amount for a predetermined period, and which can be sprayed by using a common sprayer. Specifically provided is a water dispersion type sex pheromone sustained release preparation, comprising an insect sex pheromone substance which is enclosed in a ring of a cyclodextrin, an inclusion cyclodextrin which encloses the insect sex pheromone substance, a non-inclusion cyclodextrin which does not enclose the insect sex pheromone substance, a water-soluble polymer, and water. Furthermore, provided is a method for producing a water dispersion type sex pheromone sustained release preparation, comprising at least a step of mixing an aqueous suspension of an insect sex pheromone substance which is enclosed by a cyclodextrin, with a non-inclusion cyclodextrin which does not enclose the insect sex pheromone substance, and a water-soluble polymer.
[相关专利] Sustained release dispenser comprising two or more sex pheromone substances and a pest control method 进入全文