【摘要】 <正> 棉蚜(Aphis gossypii)是棉花苗期至花铃前期的主要害虫之一。长期以来,由于大量使用化学药物,其抗药性不断增加。为了掌握棉蚜种群数量消长的一般规律,给寻找其他有效的防治方法提供依据,本文对棉蚜实验种群的数量动态与其宿主棉株的关系进行了初步探讨。现将结果报道如下。更多还原

【Abstract】 Relations between A. gossypii and cotton plants have been studied. The population dynamics of cotton-aphids consists of four stages, i. e., rise, balance, collapse and oscillation in a new level. From their invasion to pre-collapse period, the population dynamics of aphids accords with a Logistic curve, which can be expressed by the equation: N=2276.8/(1+e^7.94-0.40t).更多还原