印楝素乳油对黄曲条跳甲种群控制作用评价

Evaluation of azadirachtin against striped flea beetle,Phyllotreta striolata(F.)

在生命表方法分析的基础上 ,建立了害虫累积为害量指标 ,用以描述和比较某一时间段内害虫动态持续为害力大小 .应用该指标分析印楝素乳油对黄曲条跳甲 (Phyllotretastriolata (F .) )种群控制作用 ,结果表明 ,对成虫显著的忌避作用是其对种群控制的主要机理 .印楝素 0 .5 0ml·L-1对成虫的忌避率为83.75 % ,种群趋势指数I值降为 0 .335 4 ,干扰作用控制指数为 0 .0 86 3.采用田间试验获得的结果 ,避免了室内测定的空间限制 ,因而是评价异源植物次生化合物对害虫忌避作用的主要依据 .

Based on the idea of life table,the concept and index of insect pests accumulated damage amount were described and the damage degree and its fluctuation were compared.Through analyzing the deterrent effect of azadirachtin on the adults of striped flea beetle (SFB), Phyllotreta striolata (F.),the results showed that the control mechanism was its strongly deterrent effect. When 0.5 ml·L -1 azadirachtin was applied,83.75% of the SFB adults was kept away from the host plant. The population trend index (I value) of SFB decreased from 3.8680 in the control to 0.3354.The interference index of population control ( IIPC ) was 0.0863 at this dosage. The results come from the fields,which avoided the space limit of laboratory experiment,were the main basis to evaluate the deterrent of allogenetic plant secondary substances to insect pests. Such index provided an objective method to assess the pest damage degree,and would play an important role in the dynamic researches of pest ecological control.