抗感品种混植对水稻主要病害的效应

 1986-1988年利用抗感品种混植对水稻主要病害的效应进行了研究。结果表明:(1)对稻瘟病抑制作用显著,尤以对叶瘟效果最好(F=46.55,P<0.01)。与应发病值相比,其相对抑制效果:病叶率减少74.23%,病情指数降低85.30%。单植的病害日侵染速率(r)比混植高一倍以上。病情严重度与组合内抗感比例密切相关(r=0.951^··)且呈幂函数关系:?=3.3918×7.4446x。(2)对稻纹枯病和稻白叶枯病均有一定效应,但不如稻瘟病显著。文中还对混植机理及存在问题进行了探讨。

EFFECT OF MIXED PLANTINGS OF RESISTANT AND SUSCEPTIBLE VARIETIES OF RICE ON DISEASE DEVELOPMENT

Some investigations were made on the effect of mixed plantings of disease resistant and susceptible verieties of rice during 1986-1988. Results indicated that (1) rice blast incidence was significantly reduced, especially in leaf blast (F=46.55^**, p<0.01). The relative controlling effect on rate of laef disease and index of disease was reduced by 74.23% and 85.30% The rate parameter of disease (r)in mixtures was below as twice as pureline susceptible variety. The relationship between disease severity and proportion of resistant and susceptible in mixtures can be described in the following formula. Y=3.3918×7.4446^x (r=0.9501^**, p<0.01). (2) It was not significantly effective to rice sheath blight and Xanthomonas oryzae infection in the mixed plantings.In addition, the mechanisms of mixed planting effects and other questions are discussed.