• Korean journal of applied entomology
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• v.59 no.4
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• pp.433-441
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• 2020

This study was conducted to understand the distribution characteristics of aquatic insects in ecologically different ponds in terms of the disruption. We investigated the fauna of aquatic insects in three artificial ponds (pond 1, 2 and 3) and two natural ponds (pond 4 and 5) located within 1 km each other around Gungdaeoreum in Jeju Island, from March 2018 to June 2020. A total of 50 species belonging to 15 families were found in the surveyed ponds: total 850 individuals with 14 species in 4 families of the order Odonata, total 4,391 individuals with 14 species in 6 families of the order Hemiptera, and total 2,014 individuals with 22 species in 4 families of the order Coleoptera. In overall, total abundance and species numbers were relatively higher than those of artificial pond in natural ponds in which animal and plant ecosystems were well established. In the case of artificial ponds, the number of individuals and species recovered rapidly when reconstituted by introducing aquatic plants, etc. (Pond 1). The nymphs of Odonata were observed largely in ponds without natural enemies such as large fish, and where adults could freely access without interception by artificial structure. Phytophagous Corixidae of the order Hemiptera were abundant, and Haliplidae populations of the order Coleoptera were affected by the distribution of the plants. Accordingly, the major factors affecting aquatic insect abundance were identified as the presence of refuges such as the topography and aquatic plants and presence of predators. Species of the order, Odonata were vulnerable based on these factors. Our results can be useful as basic information for the restoration of wetlands and construction of artificial wetlands or for conservation of species diversity in the future.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.123-158
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• 2009

An attempt was made to stimulate future research by providing exemplary information, which would integrate published knowledge to solve specific pest problem caused by resistance. This review was directed to find a way for delaying resistance development with consideration of chemical(s) nature, of mixture, rotation, or mosaics, and of insecticide(s) compatible with the biological agents in integrated pest management (IPM). The application frequency, related to the resistance development, was influenced by insecticide activity from potentiation, residual period, and the vulnerability to resistance development of chemical, with secondary pest. Chemical affected feeding, locomotion, flight, mating, and predator avoidance. Insecticides with negative cross-resistance by the difference of target sites and mode of action would be adapted to mixture, rotation and mosaic. Mixtures for delaying resistance depend on each component killing very high percentage of the insects, considering allele dominance, cross-resistance, and immigration and fitness disadvantage. Potential disadvantages associated with mixtures include disruption of biological control, resistance in secondary pests, selecting very resistant population, and extending cross-resistance range. The rotation would use insecticides in high and low doses, or with different metabolic mechanisms. Mosaic apply insecticides to the different sectors of a grid for highly mobile insects, spray unrelated insecticides to sedentary aphids in different areas, or mix plots of insecticide-treated and untreated rows. On the evolution of pest resistance, selectivity and resistance of parasitoids and predator decreased the number of generations in which pesticide treatment is required and they could be complementary to refuges from pesticides To enhance the viability of parasitoids, the terms on the insecticides selectivity and factors affecting to the selectivity in field were examined. For establishment of resistant parasitoid, migration, survivorship, refuge, alternative pesticides were considered. To use parasitoids under the pressure of pesticides, resistant or tolerant parasitoids were tested, collected, and/or selected. A parasitoid parasitized more successfully in the susceptible host than the resistant. Factors affecting to selective toxicity of predator are mixing mineral oil, application method, insecticide contaminated prey, trait of individual insecticide, sub-lethal doses, and the developmental stage of predators. To improve the predator/prey ratio in field, application time, method, and formulation of pesticide, reducing dose rate, using mulches and weeds, multicropping and managing of surroundings are suggested. Plant resistance, predator activity, selective insect growth regulator, and alternative prey positively contributed to the increase of the ratio. Using selective insecticides or insecticide resistant predator controlled its phytophagous prey mites, kept them below an economic level, increased yield, and reduced the spray number and fruits damaged.