橡胶盔蚧种群动态和空间分布型研究

Study on the Population Dynamics and Spatial Distribution of Parasaissetia nigra Nietner on Rubber Plant

2005—2006年连续2年对西双版纳地区橡胶盔蚧种群数量进行调查。结果表明：橡胶盔蚧在西双版纳景洪市1年发生3代，4月上旬、7月下旬和10月下旬分别是橡胶盔蚧3个世代的发生高峰期。第2代发生持续时间最长，第1代发生持续时间最短，发生量较大。用扩散系数法、Lloyd的平均拥挤度（M°）和平均聚块性指标（M°／m），Taylor幂法则、以及1wao的M°-m回归分析法分析了橡胶盔蚧种群空间分布型，4种方法得出同样的结论，即橡胶盔蚧在橡胶树上的空间分布为聚集分布。在空间分布型的基础上，利用Iwao的M°-m回归式提出了调查虫情时的最适抽样数，建立了Iwao的序贯抽样模型。

Annual monitoring was conducted on population dynamics of Parasaissetia nigra Nietner from 2005 to 2006 in Jinghong of Xishuangbanna Prefecture. The result indicated that it had 3 genera- tions. The period of population peak of each generation occurred separately in early April, late July and late October. The duration of the second generation was the longest. The duration of the first gen- eration of the largest population was the shortest. The spatial distribution of P. nigra population was studied by the methods of diffusion coefficient, Lloyd＇s mean crowding and index of patchiness, Iwao＇s patchiness and Taylor＇s law. The results of all the methods showed that the spatial pattern of P. nigra was aggregated distribution on rubber plants. Based on the analysis of spatial distribution, the opti- mum number for sampling under different tolerances was determined and sequential sampling model was established by Iwao theory sampling model.