柑桔粉虱在柠檬园的空间分布型及抽样技术

为制定柑桔粉虱在柠檬园的合理抽样方案，对其空间分布型和抽样技术进行了研究。结果表明：柑桔粉虱在柠檬园的空间分布基本为聚集分布型，是由其种群聚集特性和环境异质性共同引起的，分布特征表现为个体间相互吸引，分布成分为个体群。以棋盘式抽样法，每株取西梢或东、南、西、北、中各一梢的基叶、中叶、顶叶调查虫情简易而准确。判断该虫发生程度的界限方程有2组，最多调查5或13株即能判断该虫的发生情况。

Spatial distribution pattern of dialeurodes citri in lemon garden and its sampling techniques

To draw up the legitimate sampling techniques of Dialeurodes citri in lemon garden spatial distribution pattern of dialeurodes citri in lemon garden and its sampling technique were studied. The result shows that the spatial distribution pattern of dialeurodes citri (Ashmead) in lemon garden is aggregation distribution, which is characterized with individual attraction and predominant individual group as core distribution pattern. The reason of aggregation is the species properties and the environmental difference. The type of chess plate sampling is easy and precise for investigating pest among the western shoot or the eastern, southern, western, northern and middle shoots of a tree and among low-, mid- and top-leaves of a shoot. There are two equations to judge the occurrence degree of the dialeurodes citri. The pest's occurr degree can be judged by investigating 5 or 13 trees at most.