杨树冰核细菌溃疡病损失估测及防治指标

Study on the Determination of the Loss of Poplar Ice Nucleation Bacterial Canker and Control Index

在东北杨树冰核细菌溃疡病重发区和发生区，分别不同树种、林龄和立地条件，选设具有代表性的样地、采用野外均匀分布、典型整群抽样调查和树干解析的方法、获得１２０块样地，２７０株解析木的调查数据，确定了病情指数与材积损失率的相关数律，建立了东北地区杨树冰核细菌溃疡病材积损失估测的模型、并以此推算出了东北地区相应的经济危害允许水平模型和防治指标的计算模型。

The representative plots were chosen and established in the areas where poplar bacterial cankeroccurred seriously in Northeast China, according to different species, ages and sites. By the method ofuniform distribution. typical population sampling and stem analysis in field. the correlation law betweenvolume loss rate and disease index was determined with the data of 270 trees of stem analysis and 120sample plots. The Logistic equation was screened out as the loss assessment model of poplar bacterialcanker in Northeast China by repression analysis of different type of curves and the correspondingmodels of economic injury level and control index were also calculated.