• Korean journal of applied entomology
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• v.61 no.2
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• pp.335-347
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• 2022

We investigated the emergence patterns of Chilo suppressalis (Lepidoptera: Crambidae) adults using sex pheromone traps in the three northeastern areas, Dandong (40°07'N 124°23'E) (Liaoning province), and Gongzhuling (43°30'N 124°49') and Longjing (42°46'N 129°26'E) (Jilin province), China, in 2020 and 2021. Two times of adult flight seasons were isolated clearly during the rice growing periods in the all areas, in which the first season from mid May to late July, and the second season from mid July to mid September were observed. The adult emergence seasons in the areas at higher latitude were later than that at lower latitude. Using the adult emergence data during the first flight seasons, the second flight seasons were estimated through insect phenology modelling, and compared with the observed data. Temperature-dependent life history models (developmental rate, development completion, survival rate, adult aging rate, total fecundity, oviposition completion, and adult survival completion) were collected or constructed for each life stage of C. suppressalis, in which the data from the four previous studies were used. Those models were combined in an insect phenology estimation software, PopModel, and operated for the observed areas. In the results, the phenology modelling operated with the models based on the data of shorter larval periods in the previous studies estimated more accurately the second flight seasons. In 2021, we investigated the change of damaged hill ratios of rice with observing the adult emergence at Dandong and Longjing, 2021. The increase periods of damaged hill ratios of rice were observed two times during the total rice cultivation season, which may be caused by different generations of C. suppressalis larvae.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.49-54
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• 2004

The oriental tobacco budworm, Helicoverpa assulta (Guenee) is a major pest of red pepper in Korea. Insecticide spray is a prevalent control tactic in most farms, but an effective control is difficult because the larvae are protected inside the fruit. Objective of this study was to investigate the seasonal occurrence of the male moths using pheromone trap and to evaluate the control efficacy of insecticide applications based on the trap catch data at red pepper fields in Suwon. The results of pheromone trap catch during three years showed that the moth flight activity occurred from late May to early October. Peak periods of the adult flight, which are indicators of each generation, occurred in late June, late July-early August, and late August-early September. Trap catches during the overwintering and first adult generation were closely linked with subsequent damage. Although the trap catch during the second generation was higher than the previous generations, damage level caused by this generation larvae was low. Experiment results revealed that fruit damage by H. assulta could be effectively reduced by five sprays of insecticides based on the trap catch data throughout the season.