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对麦收期小麦不同高度的天敌分布调查以及麦—棉邻作棉田和棉—棉邻作棉田天敌数量在麦收前后的变化调查 ,结果表明 :蜘蛛类、食虫蝽类、隐翅甲类天敌主要栖息在距地面 10cm以下麦杆及地表杂草上 ,而草蛉类、瓢虫类则主要栖息在距地面 10cm以上的麦杆上 ,而且麦田天敌在麦杆 10cm以下栖息数量远大于距地面 10cm以上的数量 ;麦收后 ,麦田的天敌迅速转移至与之相邻的棉田 ,其中 ,瓢虫类和草蛉类等飞行能力较强的天敌首先扩散 ,比蜘蛛等爬行类类天敌先进入棉田 ;麦—棉邻作棉田麦收后的天敌数量是麦收前的 2 5 .7倍 ,而且明显高于棉—棉邻作的棉田天敌数量 ;距离麦田 2 5 ,50 ,75m的棉田天敌数量在麦收前并无明显的差异 ;麦收后则明显呈现出棉田天敌数量距麦田 2 5m >距麦田 50m >距麦田 75m这一规律。
Investigation of natural enemy distribution at different heights of wheat at harvest and wheat and wheat-cotton neighbors cotton fields as the number of natural enemies before and after the close of the survey, the results showed that: spiders, insects stinkbugs, predatory wing predators Perched on straw and surface weeds under 10cm from the ground, while the grass moths and ladybugs mainly inhabit the wheat straw above 10cm from the ground, and the number of natural enemies of wheatfields is much less than 10cm below the wheat straw The natural enemies of wheat fields rapidly transferred to the cotton fields adjacent to them. Among them, natural enemies such as ladybugs and grass weeds diffused first and entered into cotton fields earlier than spiders and other reptiles; The number of natural enemies of wheat-cotton neighbors after receiving wheat was 25.7 times that of wheat before harvest, and obviously higher than the number of natural enemies of cotton-cotton neighbors. The number of natural enemies of cotton fields from 25 to 50, There was no obvious difference. After the wheat harvest, the number of natural enemies in the cotton field obviously ranged from 25 m in the wheat field to 50 m in the wheat field and 75 m in the wheat field.