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【目的】为了合理利用自然天敌,定量评价棉田自然天敌对苗蚜和伏蚜的控制作用。【方法】采用接虫罩笼法结合系统调查。【结果】发现苗蚜的主要自然天敌是龟纹瓢虫Propylaea japonica Thunberg和异色瓢虫Harmonia axyridis Pallas,大部分时间能够有效的控制苗蚜种群在防治指标以下,控害指数高达91%;伏蚜主要自然天敌是蜘蛛、草蛉和龟纹瓢虫,由于其种群数量太少,益害比低,对伏蚜控害指数始终低于20%,无法有效的控制伏蚜种群。【结论】结果提示,应根据苗蚜和伏蚜自然天敌控制作用不同,制定合理的保护利用自然天敌的策略。
【Objective】 In order to make rational use of natural enemies, the natural enemies of cotton fields were evaluated quantitatively for the control of seedling aphid and aphid. 【Method】 The method of connecting insect cage and cage system was used. 【Result】 The results showed that the main natural enemies of seedling aphid were Propylaea japonica Thunberg and Harmonia axyridis Pallas. Most of the time, they were able to control the population of seedling aphids effectively under the control index, with the control index as high as 91% The main natural enemies of aphids are spiders, weeds and ladybugs. Due to their small population and low benefit-to-harm ratio, the index of control of aphids is always below 20%, which can not effectively control the population of aphids. 【Conclusion】 The results suggest that the control strategy should be based on the different natural enemies of seedling aphids and the aphids.