【摘要】 <正> 近年来,我国在推广种植矮秆品种、杂交稻组合以及提高密植程度和施肥水平后,纹枯病为害明显加剧。当前,在防治上运用栽培技术与药剂相结合的措施,收效显著。但从长远的观点来看,培育抗病品种是防治水稻纹枯病最经济、有效的方法[1、6]。因此研究品种抗性的鉴定技术,开拓水稻纹枯病抗性种质,鉴定当前生产上常规品种的不同抗感程度,这在今后纹枯病的防治对策上,具有重要的意义。更多还原

【Abstract】 During 1982-1984.the pathogenicity of 47 isolates of Thanatephorus cucumeris fromsheath blight in different rice growing regions in China was tested.Three varietieswith different degrees of resistance were selected as differential varieties,namelyJinggong 30,IET 4699 and IR 9752.The pathogenicity difference of interactions betweenvarieties and isolates was significant according to their different disease indexes.Sofar as we tested no specificity was found,Based on the colouration of cultural substratethe luxuriousness of mycelial growth and the amount and size of sclerotium on PSAcultural medium 47 isolates were classified into three cultural types.It was evidentlyrelated to the pathogenicity differentiation of pathogens and their cultural types onPSA medium In general.when the isolate produced a light colour of cultural substrate,luxuiant aerial mycelium and a small amount of sclerotium,the pathogenicity of thisisolate was lowFour artificial inoculation methods.segment-warp-inoculation,stem-tape-inoculation,mycelium-spray-inoculation and in vitro inoculation were compared.The resultsindicated that the stem-tape-inoculation method was simple,easy and suitable forscreening a large number of rice varieties in the field.Three resistant varieties of indica rice(Tetep,IET4699,Jaw No.14)and threemoderately resistant local varieties of japonica rice(Lucahong,Sishehungxiaobaiyinsinghong)were selected from 49 rice varieties collected from various regionsfor field identificatiton of sheath blight resistance in 1983-1984.更多还原