不同木薯品种上木瓜秀粉蚧空间格局研究

Study on spatial patterns of Paracoccus marginatus on different cassava species

木瓜秀粉蚧(Paracoccus marginatus)是木薯上一种重要的害虫,明确木薯上该虫空间分布是虫口调查的基础。本文调查获取了多个木薯品种上木瓜秀粉蚧分布数据,采用聚集度指标、Iwao的M*-m回归法、Taylor幂法则、Lα-m回归模型和Z-V模型等方法研究了该粉蚧的空间格局,结果表明木薯上木瓜秀粉蚧在密度较低时呈均匀分布或聚集分布,密度高时呈聚集分布。在木薯叶层上的数量总体呈现下层>中层>上层,在桂热4品种上木瓜秀粉蚧密度较大,桂热891品种上密度最低。

The whitefly,Paracoccus marginatus,is a major pest of cassava.To clarify the spatial distribution of this worm on the cassava is the basis of the insect population investigation.In this paper,we obtained the distribution data of Paracoccus marginatus on several cassava varieties,and studied the spatial patterns by using aggregation indices,Taylor’spower law,Iwao’s M*-m regression analysis,Lan’s Lα-m model and Zhang’s Z-V model.The results showed that the spatial distribution pattern of Paracoccus marginatus distributed evenly or sggregated when its population density was low,but sggregated when its population density was high.The numbers of Paracoccus marginatus on the different leaf layers were different,with the sequence of lower leaves>middle leaves>upper leaves.The density of Paracoccus marginatus on GR4 was the most,GR891 was the least.