桑园主要害虫的空间分布型研究

为了了解害虫种群的重要属性，笔者运用5种聚集度指标和2种回归分析方法，对桑园3种主要害虫桑白粉虱（Bemisia myricae Kuwana）、桑螟（Diaphania pyloalis Walker）、朱砂叶螨（Tetranychus cinnabarinus Boisduval）的空间分布型和抽样技术进行研究。结果表明，白粉虱随机分布型和均匀分布型中间偏于随机分布型，朱砂叶螨为聚集分布和随机分布型中间偏于随机分布型，桑螟为随机分布型和均匀分布型中间型，结果为这3种害虫的种群系统研究奠定了良好的基础。

Spatial Distribution Pattern of 3 Pests in Mulberry Field

In this paper,the spatial distribution pattern of 3 pests Bemisia myricae Kuwana,Diaphania pyloalis Walker,Tetranychus cinnabarinus Boisduval were analyzed with Taylor’s power law,Iwao’s distribution function,and 5 aggregation indexes.The results showed that the spatial distribution pattern of B.myricae was between uniformly distribution and random distribution,but tended to the latter,T.cinnabarinus was between aggregated and random distribution,but tended to the latter,and D.pyloalis was between uniformlyd istribution and random distribution.By using the parameters α and β in Iwao’s M ＊ -M regression equation,the optimal sampling numbers were determined.