中国东北地区玉米纹枯病菌的融合群鉴定

自东北三省采集玉米纹枯病标本300余份，分离获得286个丝核菌菌株。融合群测定及5.8S rDNA-ITS区序列分析结果表明，这些菌株分别属于多核丝核菌的AG1-IA、AG1-IB、AG1-IC、AG4-HG-I、AG4-HG-III、AG-5、WAG-Z群及双核丝核菌的AG-Ba群。其中AG1-IA是优势致病群，占分离菌株总数的38.46%，其次是WAG-Z和AG-5群，分别占26.92%及24.83%。AG4-HG-III群菌株是国内首次从罹病玉米植株上分离得到。自各融合群中选取代表性的菌株进行5.8

The anastomosis groups of the corn sheath blight pathogen Rhizoctonia spp. in northeastern China

Two hundred and eighty-six isolates were obtained from corn sheath blight samples in northeastern China (including Heilongjiang, Jilin and Liaoning provinces). Anastomosis group identification and 5.8S rDNA-internal transcribed spacer (ITS) sequence analysis showed that the isolates belonged to multinucleate Rhizoctonia AG1-IA, AG1-IB, AG1-IC, AG4-HG-I, AG4-HG-III, AG-5,WAG-Z and binucleate Rhizoctonia AG-Ba. Of these, AG-1-IA was the major anastomosis group (AG) (38.46% of total isolates), followed by WAG-Z (26.92%) and AG-5 (24.83%). AG4-HG-III was isolated for the first time from maize in China. 5.8S rDNA-ITS sequence analysis showed that the isolates could be distinctly separated based on their AG types. The isolates belonging to the same AG (or sub-AG) showed high sequence identity.