不同作物上棉蚜及其主要天敌的发生规律

随着化学农药的大面积推广使用，棉蚜的抗药性问题变得越来越突出，结合使用生物防治法来延缓或治理棉蚜抗药性问题已迫在眉睫。本研究在常规管理棉田条件下，对不同作物混栽区苗期6种作物上棉蚜及其主要天敌的种群动态进行了调查。结果表明，西葫芦上的棉蚜种群数量最大（峰值，11016.7头/百株），其次是四季豆（峰值，6323.3头/百株），棉花、黄瓜、豇豆和甜瓜上的棉蚜则相对较少，且其种群动态发生具有一致性。6种作物上的主要天敌的种群发生都滞后于棉蚜的发生，并以寄生蜂的种群密度最大，且具有指数增长效应。在本试验条件下，西葫芦上棉蚜数量多，僵蚜基数大，是室内饲养寄生蜂的良好寄主。

Population Dynamics of Cotton Aphid and Its Major Natural Enemies on Different Crops

With the large-scale uses of chemical pesticides, insecticide resistance of cotton aphid is becoming more and more prominent, necessitating the use of biological control to delay or control resistance development in cotton aphid. In this study, the dynamics of cotton aphids and their main natural enemies were investigated at seedling stage in six crops under conventional conditions. The results showed that the number of cotton aphids on zucchini was the highest (peak 11016.7/100 plants), the second on kidney bean (peak, 6323.3/100 plants), on cotton, cucumber, cowpea and muskmelon, was relatively low. Population dynamics were temporally consistent. The occurrence of the major natural enemies of aphids on the six crops lagged behind the occurrence of cotton aphid. Density of parasitic wasps was the largest among the natural enemies and showed an exponential growth pattern. Population size of cotton aphids and mummified aphids on zucchini was the largest, suggesting that zucchini is a good host plant for rearing the parasitic wasps.