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采用分期调查病情与孢子捕捉的方法,通过引入模糊集论中基于模糊等价关系的模糊聚类分析,将发病数量(病害强度)、空间和时间动态的相互关系联系起来,作为统一体,研究了小黑杨灰斑病的流行动态。将其化分为SS_1、SS_2、SS_3、SS_44个亚系统提出了灰斑病发展的进程为:始期、始盛期、盛期、末期4个阶段,同时对多个因子进行了逐步回归筛选,选出了以病原基数、五月份降雨为关键因子的侵染期、发生期、发病始期、盛期、末期病情的预测模型。研究表明:自树木展叶后日降雨在1.2mm以上时为侵染期;侵染期加潜育期为发生期,即T=t_1+t_2。
Using the method of staging investigation of disease and spore catching, by introducing fuzzy cluster analysis based on fuzzy equivalence relation in fuzzy set theory, the relationship between disease incidence (disease intensity) and spatial and temporal dynamics is linked and taken as a unified body The Populus gray spot disease epidemic. The subdivided into SS_1, SS_2, SS_3, SS_44 subsystems put forward the process of gray leaf disease development as: the initial period, the beginning of the peak, peak and end of the four stages, at the same time, a number of factors were screened by stepwise regression, The forecasting model of infection, occurrence, onset, peak and end of disease with the base of pathogen and rainfall as the key factor in May was selected. The results show that: when the trees show leaf fall, the infection period is more than 1.2mm, while the incubation period is the occurrence period, T = t_1 + t_2.