广西玉米纹枯病菌的菌丝融合群及其对杀菌剂的敏感性

从广西21个县(市)的采集玉米纹枯病标本,经分离纯化后获得126个丝核菌属菌株,其中多核丝核菌121株,双核丝核菌5株。菌丝融合群测试结果表明,多核丝核菌分别属于AG-1-IA(85.17%)、AG-1-IB(1.59%)、AG-4(3.87%)和AG-5(4.76%)融合群,双核丝核菌分别属于AGBb(2.38%)和AGK(1.59%)融合群。首次从玉米上分离到双核丝核菌AGBb融合群。不同融合群对4种供试杀菌剂的敏感程度存在明显的差异。AGB(b)、AG和AG-1-IB对供试杀菌剂多表现为高度的敏感性,AG-4和AG-5融合群则表现为中度的敏感性,而AG-1-IA敏感性最小。

The Anastomosis Groups of Corn Sheath Blight in Guangxi and Their Sensitivity to Fungicides

One hundred and twenty-six isolates of Rhizoctonia spp. were obtained from tissues of corn sheath blight in 21 counties of Guangxi. They were divided into series of Rhizoctonia; multinucleate and binucleate series. According to the hyphal fusion with the international standard isolates of anastomosis groups(AGs)of Rhizoctonia, the multinucleate belong to AG-1-IA(85.17% ), AG-1-IB(1.59%), AG-4(3.87% )and AG-5 4.76%,the binucleate series belong to AG-Bb(2.38%) and AGK((1.59%)), respectively. The isolates of AGBb were first found in corn. There were significant differences in sensitivity to the tested fungicides among different AGs. The isolates of AGB(b), AGK and AG-1-IB had the strongest sensitivity, the isolates of AG-4 and AG-5 were moderate, and the isolates of AG-1-IA had the least sensitivity to the tested fungicides