【摘要】 本文通过1990～1991年两年的田间系统调查,研究了大豆蚜自然种群的空间动态规律。大豆蚜在豆株上的空间分布随时间序列表现出明显的规律性变化,即前期从豆株上部向下部转移,后期则由下部向上部转移。应用聚集度指标分析大豆蚜田间种群在整个发生过程中,呈聚集分布,但不同时期聚集程度不同,在发生为害盛期近于随机分布。更多还原

【Abstract】 The space distribution of soybean aphis on plant has the obvious principle in accordance with time sequence, that is, soybean aphis moves from top part of plant to below part of plant in early period and from below part of plant to top part of plant in late period. The farm species group of soybean aphis shows aggregate distribution in its present process according to analysis of aggregate index, but aggregate degree of soybean aphis varies in defferent period and is nearly random distribution in its damaging popular period.更多还原