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利用陕西汉中地区 2 4年 ( 1 974～ 1 997年 )的小麦条锈病病情、菌量、品种和气象资料 ,采用逐步回归法分析了影响汉中小麦条锈病流行的因子 ,求得最优回归子集 ,包括春季菌量、秋季菌量、感病品种面积比例、4月份降雨量和 4月份平均温度。用前 2 0年资料建立了多元线性回归方程 ,对 1 994～ 1 997年小麦条锈病的流行程度作短期预测 (以残差绝对值≤ 0 .5为标准统计 ) ,结果表明 ,方程预测的准确率为 75%
By using stepwise regression analysis, the factors that affected the prevalence of stripe rust of wheat in Hanzhong were analyzed by using the data of wheat stripe rust, bacterial count, species and meteorological data from 1974 to 1997 in Hanzhong, Shaanxi Province, China. The optimal regression Set, including the amount of spring bacteria, the amount of autumn bacteria, susceptible varieties of area ratio, April rainfall and average temperature in April. Using the data from the previous 20 years, a multiple linear regression equation was established to make a short-term prediction of the prevalence of wheat stripe rust from 1994 to 1997 (based on the absolute value of the residuals ≤0.5). The results show that the predicted The accuracy rate is 75%