稻粒黑粉病已成为杂交稻制种田的重要病害,病粒率一般达10％左右。因此各地对其研究逐渐增多,但对其主要发病因素特别是防治指标报道甚少。本文通过田间试验、大田调查、室内考种并结合气象资料分析,在这方面对其进行了探讨。结果表明,杂交稻品种及其不育系、同一不育系的不同播期、不同施肥量及气候与稻粒黑粉病发病关系密切,而密度与发病关系不密切。稻粒黑粉病单穗病粒数与产量损失的关系为:Y=-2.645+1.320X(r=0.9587~(**)),防治指标为病粒率1.26％。 Rice powdery mildew has become an important disease in hybrid rice farming, the disease rate is generally about 10%. Therefore, its research gradually increased everywhere, but its main risk factors, especially prevention and control indicators have been reported very little. In this paper, field experiments, field surveys, indoor test species combined with meteorological data analysis, in this regard, it is discussed. The results showed that the different sowing dates, different fertilizers and climate of hybrid rice varieties and their CMS lines and the same CMS line were closely related to the incidence of rice powdery mildew, but the relationship between the density and incidence was not close. The relationship between the grain number and the yield loss of rice grain smut disease was Y = -2.645 + 1.320X (r = 0.9587 ~ (**)), the control index was 1.26%.