李始叶螨种群密度估计方法的研究

根据空间格局研究中获得的资料,对李始叶螨Eotetranychus pruni Oudemans种群的抽样技术进行了研究。结果表明:田间随机取样以“Z”字型方式为最佳,最适抽样单位为1个叶片;建立了利用无螨叶率(P₀)估计种群密度(x)的关系式:x=4.2134(-lnP₀)^1.2729(r=0.979);提出了李始叶螨种群的理论抽样数模型、序贯抽样模型和用于指导防治的序贯抽样模型。确立了二阶抽样技术中所抽取的树数(l)与叶片数(k)的配额公式为:kl=(tcv)²·(9.1138km^-0.9546+5.5412m^-0.4248)

Studies on Methods for Estimating the Population Density of Eotetranychus Pruni Oudemans

Based on the spacial patterns of Eotetranychus pruni Oudem ans,the sampling techniques were studies in this paper.The results are as follows: 1) "Z" type is the most accurate among the random sampling methods,and the most suitable sampling unit is a leaf. 2). The relation between mite rate in leaves(P₀)and mean density(x)is presented as the formula:x=4.2134(-lnP₀)^1.2729(r=0.979) 3) Depending on the Taylor''s power law,the theoretical sampling amount model,the sequential sampling model and sequential sampling model can be used to direct the control of the mite were proposed. 4). The formula about the optimum disposal of the sampling number between trees and leaves in two-stage sampling methods is kl=(tcv)²·(9.1138km^-0.9546+5.5412m^-0.4248).