油葵叶螨空间发生格局及其应用技术研究

Study on the Spatial Pattern and Samlping Technique of Oil Sunflower Leaf Mites

通过空间发生格局指标测定 ,截形叶螨在油葵田水平发生格局呈均匀分布。在植株各叶层上的垂直分布具有明显的层次性 ,发生格局表现为中部呈均匀分布 ,上下层均呈聚集分布。当油葵发育到 1 8叶片时 ,叶螨主要分布在第 4～ 1 4叶层上 ,占总螨量的 92 .6% ,不同田块之间差异不显著。田间理论抽样数由 :N=(1 .64/ D) 2 (1 .2 67/ X-0 .1 5 9)给出 ,且每株抽取第 4～ 1 4叶层中任意 3叶 ,即可进行田间虫口发生量的估计。

Based on the measuring of spatial pattern indexes,the level occurrence pattern of oil sunflower leaf mites( Tetranychus truncatus )showed uniform distribution,the vertical distribution among oil sunflower stem leaf layers had uniform distribution in middle part while a gathering distribution in up and down layers.When sunflower growed with 18 leaves,leaf mites mainly distributed on the 4th～14th leaf layers,the number of which account for 92.6% in total.There was no difference about the distributive numbers in the different fields.The number of most suitable theoretical sampling of leaf mite in oil sunflower field was given by the N=(1.64/D) 2(1.267/ -0.159).