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【目的】棉蚜Aphis gossypii是新疆棉田的主要害虫,近来的研究多集中于南疆棉区,较少关注北疆棉田在新种植模式下的天敌种群数量发生规律。本文研究了北疆棉田棉蚜的优势种捕食性昆虫数量发生规律。【方法】对五家渠地区棉田中棉蚜及其4种主要捕食性天敌昆虫(2种瓢虫和2种草蛉)的种群数量进行了持续2年的跟踪调查。【结果】不同种捕食性天敌昆虫对棉蚜种群数量变化具有不同的响应,具体表现为:七星瓢虫Cocinella septempunctata数量随蚜虫数量增大而显著增大,多异瓢虫Hippodamia verigata和普通草蛉Chrysopa carnea随蚜虫数量增大而逐渐增大,而大草蛉Ch.septempunctata种群数量与棉蚜数量无关;连续2年的大田调查均发现,这4种捕食性昆虫种群数量在7月底有一高峰,而且七星瓢虫和大草蛉数量大于多异瓢虫和普通草蛉。【结论】七星瓢虫和大草龄是北疆五家渠地区棉田棉蚜的优势天敌。
【Aim】 Aphis gossypii is a major pest in Xinjiang cotton field. Recently, most studies have focused on the southern cotton area, with less attention paid to the occurrence of natural enemy population in northern Xinjiang. In this paper, the dominant species of cotton aphid population in northern cotton bollworm occurrence of predacious insects. 【Method】 The population of Aphis gossypii and its four main predatory natural enemies (two kinds of ladybugs and two kinds of weeds) in Wujiaqu area were investigated for two years. 【Result】 Different populations of predatory natural enemies had different responses to changes in the population of cotton aphids. The results showed that the numbers of Cocinella septempunctata increased significantly with the increase of aphids, and Hippodamia verigata and common grass bream Chrysopa carnea increased gradually with the increase of aphids, but the population of Ch. Septempunctata was not related to the number of cotton aphids. For 2 consecutive years of field investigation, the population of these 4 species of predatory insects reached a peak at the end of July, The number of ladybugs and ladybugs is greater than that of ladybugs and common weeds. 【Conclusion】 Coccinella septempunctata and Da-ge-ling are the predominant natural enemies of cotton aphid in Wujiaqu area of northern Xinjiang.