苦皮藤乳油对小菜蛾种群的控制作用

通过室内外系统试验探讨了体积分数1％苦皮藤乳油对小菜蛾（Plutella xylostella L.)种群的控制作用，并采用生命表技术进行评价。结果表明，其控制作用主要表现在对成虫产卵的忌避作用、对幼虫的拒食作用以及对生长发育的影响和减少幼虫危害力等方面。体积分数1％苦皮藤乳油10.00mL/L处理对成虫的忌避率为73．2％，对幼虫的选择性和非选择性拒食率分别为94．7％和93．5％，幼虫总取食量是对照的40．1％，使小菜蛾种群趋势指数（I值）由对照的21．954降为0．6684，干扰作用控制指数（IIPC）为0．0304。采用状态空间分析法就苦皮藤乳油施用后小菜蛾种群数量动态的模拟分析亦表明，其显著的控制作用表现在种群发展初期对成虫产卵的忌避作用。

The Effect of Celangulim against Diamond Back Moth, Plutella Xylostella L.

Effect of celang ulim dosages on population dynamics of the diamond back moth(DBM), Plutella xylostella,was investigated in both laboratory and field,and evaluation was carried out with life-table technology.The results showed that celangulim strongly deterred the adult from laying eggs and significantly inhibited larval feeding on the plant with it.When 10.00 mL·L^-1 of celangulim was applied,73.2% of the adults of DBM was kept away from the host plant,and the selective and non-selective antifeedant rate were 94.7% and 93.5% respectively.Total food intake by DBM larva decreased to 40.1% of that in the control.The index of population trend of DBM decreased to 0.6684 from 21.954 in the control.The interference index of population control was 0.0304.Based on the space-state equation of cybernetics,models of DBM population dynamics were set up,which indicated key role of deterrent activity of celangulim on the adult egg-laying in control of the population.