麦田天敌对麦蚜控制作用的考察

 小麦蚜虫是云南省小麦的主要害虫,常年蚜害损失10%至20%,严重时可达30%以上。长期以来主要用化学杀虫剂防治,不仅方法单一使得蚜虫产生了抗药性,不得不提高药剂使用的浓度和数量,导致农业成本增加、农药污染环境和影响小麦的品质。为了探索在综合防治中充分发挥天敌因子的作用,减少农药对环境的污染,建立农田生态系统的良性循环,提高小麦的质和量,1984年至1985年对麦田天敌昆虫控制麦蚜的作用进行了观察。在相同的栽培耕作条件下,保护和利用天敌的麦田内各种天敌繁衍兴盛,共同控制着麦蚜的数量和为害,表明了在综合防治中积极保护和利用天敌的重要性。

An Investigation on the Role of Natural Enemies Suppressing the Wheat Aphids

Nine major species of predators and two species of parasites of aphids were found in the wheat fields from 1980-1981 in the suburbs of Yu Xi and Kunming cities, yunnan Province. Among them the predatory insects, i. e. lady beetles, play an impor rant role in the population regulation of wheat aphids, when the insecticides were applied, both aphids and natural enemies were killed. Aphids population recovered rapidly, while their natural enemies took longer to increase and therefore a valuable pest control agent was lost. At the wheat fields where the natural enemies were conserved, and meantime lady beetles were released, the wheat aphids population decreased singnificantly. In addition, the wolf spiders and the dwarf spiders as well as some species of hover flies togather with lady beetles play an important role in the population regulation of wheat aphids.