生草苹果园主要害虫和天敌的生态位研究

为了明确果园生草对果园病虫害的影响，调查了生草苹果园不同时期苹果主要害虫及其天敌自然种群的数量，从而获得各期害虫与害虫、害虫与天敌、天敌与天敌之间的生态位宽度和重叠指数，分析了它们彼此在空间及时间维度上的竞争关系。结果表明，生草果园害虫优势种为绣线菊蚜和山楂叶螨；天敌资源丰富，优势种为大草蛉；在空间维度上害虫之间存在较大竞争，主要天敌之间种间竞争也很激烈，天敌与主要害虫在空间上相遇机率较大；生草果园天敌对主要害虫绣线菊蚜和山楂叶螨在时间维度上有较强的追随效应和控制作用。

The Ecological Niche of Main Pests and Natural Enemies in Grassing Apple Orchard

In order to explicating the influence of grassing in apple orchards on diseases and pests, main pests and natural enemieswere investigated in grassing apple orchard.The single dinensional niche overlaps and nichewidthson the tine and spaceweremeasured for them by use of Hurlbert''s niche overlap format and Levins''s niche with ways on the time and space. The competition between them were analyzed. The results showed that in apple orchard majority species of pests were Aphis citricola Vander Goot and Tetranychus viennensis Zacher Resources of natural enemies were rich and majority was Chrysopa septempenctata Wesmael Pests had strong competition, natural enemies were so. Natural enemies and major pests couldmeet very often. They had strong pursuing and control effect to Aphis citricola Vander Goot and Tetranychus viennensis Zacher from time dinension.