Seasonal Occurrence, Soybean Damage and Control Efficacy of Bean Bug, Riptortus clavatus Thunberg (Hemiptera: Alydidae) at Soybean Field in Honam Province

摘要

This study was conducted to determine Seasonal Occurrence, soybean damage and control efficacy of bean bug, Riptortus clavatus Thunberg at soybean field in Honam province. Occurrence of R. clavatus varied at seeding times with annual difference. The peak occurrence of R. clavatus was appeared at late of August for late May seeding and middle of September for middle June seeding. There was difference in the peak occurrence of R. clavatus due to different growing stages affected by different weather conditions though soybean was seeded at same time. If the rate of soybean seed damage area by R. clavatus sucking increases, the germinating rate was greatly decreased. If the rate of soybean seed damage area is above 50 percent, in particular, the germinating rate was very low with 2 percent. Control efficacy against R. clavatus was the highest with 91% at 3 times treatment of insecticide at R_4 (full pod stage)+ R_5 (Beginning seed stage)+R_6 (full seed stage) of soybean growing stages in field.