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根据１９９１～１９９７年辽宁铁岭地区蚜虫天敌和麦蚜的多年多点田间调查材料分析，证明天敌复合种群与麦蚜的发生时期、密度的消长存在着跟随现象。经药剂处理后跟随现象同样存在。蚜虫天敌上升与麦蚜下降的转折点约在６月５日，此时的天敌与蚜虫比约为１∶１３０。
According to the multi-year field investigation data of natural enemies of aphids and wheat aphids from 1991 to 1997 in Tieling area of Liaoning Province, it was proved that there existed a follow-up phenomenon of the occurrence and density of natural enemies composite population and wheat aphids. After the same treatment after the phenomenon also exists. The turning point of the rise of aphids and the decline of wheat aphids is about June 5, when the ratio of natural enemies to aphids is about 1: 130.