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对黑龙江省尚志市一面坡林场樟子松枯梢病发病区内的固定标准地进行了调查。结果表明 :5月初孢子开始飞散 ,随着平均气温、相对湿度和降雨量的增加 ,孢子的飞散量也逐渐增加。 6月中旬和 6月下旬为初始发病期 ,7月下旬至 8月中旬为发病高峰 ,9月中旬为病害的终止期。气温、相对湿度和降雨 3个因子对病情的发生和发展影响很大 ,气温对病害流行始发期和终止期起决定作用。在适宜的气温范围内 (2 0～ 2 3℃ ) ,病情随时间及相应的气温、降雨量的增加而增加。同时运用逐步回归分析方法 ,建立了多元线性回归预报方程 :y =- 10 .6 +1.2 4 1y0 +0 .2 88t,入选的自变量有初始病情y0 和前月平均气温t两个因子 ,此方程可以预测当年病情指数 (y)。
Heilongjiang Province, Shangzhi City, one side slope forest pine needle disease incidence of fixed areas were investigated. The results showed that the spores began to scatter at the beginning of May. With the increase of average temperature, relative humidity and rainfall, the spore scattering gradually increased. In mid-June and late June, the initial period of onset, the peak from late July to mid-August, and the termination of the disease in mid-September. The three factors of temperature, relative humidity and rainfall have a great influence on the occurrence and development of the disease, and the temperature plays a decisive role in the onset and termination of the disease epidemic. In the appropriate temperature range (20 ~ 23 ℃), the disease with time and the corresponding increase in temperature and rainfall. At the same time, stepwise regression analysis method was used to establish the multivariate linear regression prediction equation: y = - 10 .6 +1.2 4 1y0 +0 .2 88t, the selected variables have initial condition y0 and the previous month average temperature t two factors, the equation Predict the year disease index (y).