白三叶草生长期西花蓟马的空间分布型变化

The changes of spatial distribution of Frankliniella occidentalis during the Trifolium repens' growing season

利用聚集度指标检验和比较频次法对白三叶草Trifolium repens生长期间西花蓟马Frankliniella occidentalis的空间分布型变化进行研究,结果如下:聚集度指标检验分析表明西花蓟马在白三叶草上的空间分布为聚集分布;利用频次拟合分析表明白三叶草上大部分生长期内其分布型为负二项分布,其聚集程度与虫口密度有关系,其空间分布不会因为一些人为干扰而改变。

The changes of spatial distribution of Frankliniella occidentalis during the Trifolium repens＇ growing season were examined by aggregation indices and methods of comparative frequency. The result showed that the spatial distribution of this pest in the Trifolium repens fields was aggregated during grow- ing season by four kinds of aggregation indices, and further studies through the analysis of comparative frequency indicated that it was negative binomial distribution during the majority growing season. The level of aggregation related with density of this pest. The spatial distribution of this pest couldn＇t be changed by some artificial interferance.