作　　者： ; ; ; ; ; ;

机构地区： 华南农业大学资源环境学院

出　　处： 《中国水稻科学》 2011年第2期206-212,共7页

摘　　要： 为了探明华南地区水稻纹枯病菌的生物学性状、致病力分化与菌株地理来源之间的关系,为该病害的防治提供依据,从我国华南3省（区）广东、广西和海南的33个县（市）采集水稻纹枯病标本,在分离到335个水稻纹枯病菌菌株的基础上,对它们的培养性状（菌丝生长速率、菌落颜色、菌核数量）、菌丝融合群、菌丝细胞核数目以及致病力分化进行了研究。结果表明,菌株菌丝生长速率可划分为慢、中、快3种类型,菌株数分别为3株（0.90%）、136株（40.60%）和196株（58.50%）;产生菌核的数量可划分为4种类型,即无菌核或极少形成菌核、菌核量少、菌核量中等和菌核量多,各有4株（1.19%）、59株（17.61%）、238株（71.04%）和34株（10.15%）。菌株融合群测定结果表明,所有供试菌株均属于立枯丝核菌（Rhizoctoniasolani）AG-1融合群的ⅠA亚群,即AG-1ⅠA。从中随机选取50个菌株进行菌丝细胞核染色,结果显示,水稻纹枯病菌菌丝的细胞核数目介于7~13个。对其中270个菌株的致病力测定结果表明,所有供试菌株可划分为中等致病力和强致病力2个致病型,分别为208株（77.04%）和62株（22.96%）,未发现弱致病力菌株。综合分析表明,所测菌株的致病型与菌丝生长速率及菌核产生数量各异,表现出较大的多样性。 In order to elucidate the relationship among the biological characteristics,pathogenicity and geographic origin of isolates of Rhizoctonia solani,the causal agent of rice sheath blight,so as to provide evidences for controlling the disease in South China,with a total of 335 isolates of R.solani collected from 33 counties of 3 provinces（Guangdong,Guangxi and Hainan） in South China,cultural characteristics（hyphal growth rate,colony colour and sclerotium number）,hyphal anastomosis groups,number of hyphal cell nuclei and pathogenicity differentiation were investigated.The hyphal growth rates could be divided into three types,i.e.slow,moderate and fast,with isolate numbers of 3,136 and 196,which accounted for 0.90%,40.60% and 58.50% of the total isolates,respectively.The number of sclerotia produced on PDA medium in all the isolates could be divided into four different types,i.e.absence or rare,less,moderate and abundant sclerotia,which accounted for 1.19%,17.61%,71.04% and 10.15% of the total isolates,respectively.The anastomosis grouping confirmed that all the tested isolates belonged to AG-1ⅠA of R.solani.The hyphal cell nuclear numbers of the 50 randomly selected isolates were between 7 and 13.The 270 tested isolates could be divided into only two pathotypes,i.e.moderate and high virulence with isolate numbers of 208 and 62,which accounted for 77.04% and 22.96%,respectively,no isolate with weak virulence was found.Taken together,the results revealed that there existed differences in pathotype and hyphal growth rate as well as the number of sclerotia among the tested isolates,showing more diversity.

关 键 词： 水稻纹枯病菌 培养性状 菌丝融合群 致病力分化

领　　域： [农业科学] [农业科学]