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小麦叶锈病危害造成损失,轻者减产3%,重者减产25-30%,减产程度与发病早晚,病情轻重呈正相关。经回归分析,以开花期病指数对产量影响最大。减产的主要因素是千粒重降低,其次是穗粒数减少。感病品种比中抗(慢锈型)品种发病重、流行速度快、危害损失重。依据回归方程(?)=1.4791x_1+0.1093x_2+0.0208((?)-产量损失率,x_1-开花期病指数,x_2-乳熟期病指数)预测,感病品种亩产250公斤水平的经济阈限病指:开花期为1.07,乳熟期为14.5,它随着产量水平的提高而降低。
Wheat leaf rust damage caused by the loss of light 3%, 25% -30% weight reduction, the extent of the reduction and the incidence of disease sooner or later, the severity of the disease was positively correlated. By regression analysis, the florescence index had the greatest impact on the yield. The main factor is the reduction of 1000-grain weight reduction, followed by the reduction of grains per spike. Susceptible varieties than Zhongkang (slow-rust type) the incidence of heavy, popular fast, harm the loss of weight. According to regression equation (?) = 1.4791x_1 + 0.1093x_2 + 0.0208 ((?) - yield loss rate, x_1-flowering period disease index, x_2-milk disease stage disease index) predicted that the susceptible species would produce 250 kg per mu Threshold disease means: the flowering period is 1.07, the milk ripening period is 14.5, it decreases with the increase of the yield level.