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期 刊 ：植物保护学报 2009年

关键词：阿维菌素；二化螟；稻纵卷叶螟；天敌；生物活性；

Keywords:avermectins, Chilo suppressalis, Cnaphalocrocis medinalis, natural enemy, bioactivity,

摘 要 ：采用点滴法在室内测定了阿维菌素对水稻二化螟和稻纵卷叶螟的生物活性,并研究其田间防治效果及对天敌的安全性。室内毒力测定结果表明,阿维菌素对二化螟和稻纵卷叶螟的LD₅₀值分别为0.0199μg/g和 0.0252μg/g,其活性分别是丙溴磷的37.48倍和17.59倍、毒死蜱的36.24倍和21.42倍。田间试验结果表明,1.8%阿维菌素乳油(ai) 9~18g/hm²处理对水稻二化螟和稻纵卷叶螟的防治效果分别为74.08%~82.22%和79.04%~87.19%,显著优于对照药剂50%丙溴磷乳油 (ai) 360g/hm²处理和480g/L毒死蜱乳油(ai) 360g/hm²处理。阿维菌素对稻田天敌蜘蛛和黑肩绿盲蝽的消长有一定影响,9~13.5g/hm²处理药后14天对蜘蛛和黑肩绿盲蝽虫口减退率分别为18.75%~30.21%和22.57%~33.94%,显著低于对照药剂丙溴磷360g/hm²处理和毒死蜱360g/hm²处理;18g/hm²处理药后14天对蜘蛛和黑肩绿盲蝽虫口减退率分别为47.92%和39.29%,与两对照药剂无显著差异。

Abstract:The bioactivity of avermectins to Chilo suppressalis and Cnaphalocrocis medinalis were determined with topical application in the greenhouse, its efficacy to C.suppressalis and C.medinalis and the influence to natural enemies were tested in the paddy fields. The laboratory bioassay results indicated that the LD₅₀ values of avermectins to C.suppressalis and C.medinalis were 0.0199μg/g and 0.0252μg/g, respectively. It bioactivities were 37.48 times and 17.59 times as high as those of profenofos, 36.24 times and 21.42 times as high as those of chlorpyrifos, respectively. In a field experiment, control effects of 1.8% EC avermectin at the rate of 9-18 (ai)g/hm² to C.suppressalis and C.medinalis were 74.08%-82.22% and 79.04%-87.19%, respectively, significantly higher than that of 50% EC profenofos and 480g/L EC at the rate of 360 (ai) g/hm². The dropping rates of 1.8% EC avermectins at the rate of 9-13.5 (ai) g/hm² to the spiders and Cyrtorhinus lividipennis were 18.75%-30.21% and 22.57%-33.94% on the 14th day after spraying insecticides, significantly lower than that of 50% EC profenofos and 480g/L EC at the rate of 360 (ai) g/hm². The dropping rates of 1.8% EC avermectins at the rate of 18 (ai) g/hm² to two kinds of natural enemies were 47.92% and 39.29%, respectively, equal to that of two chemical control insecticides.

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