Seasonal occurrence pattern and within-plant egg distribution of bean bug, Riptortus pedestris (Fabricius) (Hemiptera: Alydidae), and its egg parasitoids in soybean fields

摘要: A study on the seasonal occurrence and within-plant distribution of Riptortus pedestris (Fabricius) (Hemiptera: Alydidae) its two egg parasitoids was conducted to evaluate effectiveness as a biological control agent in soybean fields. We sampled plants during planting seasons 2007 2008 Andong, Korea. Adult R. deposition began at R2–R4 stage soybean. Nymphs started appear R5 Peak population densities both eggs adults were recorded soybean, whereas that nymphs R6 stage. Seasonal total parasitism by Ooencyrtus nezarae Ishii (Hymenoptera: Encyrtidae) significantly higher than Gryon japonicum (Ashmead) Scelionidae). For eggs, 90% found leaves 70% under-leaf surface. Egg O. leaf surface pods. Results suggest starts occur stages field soybeans regardless seed sowing time, density peaks after Sampling is an alternative method measure populations since most are leaves. Since synchronous with bugs' occurrence, it would be more efficient G. japonicum.