新疆北疆棉田立枯丝核菌菌丝融合群及其营养亲和群研究

从新疆北疆棉区采集了典型的棉花立枯病病苗及棉田土标样686份,按常规分离方法分离得到399个分离物,从中鉴定出272个纯化的立枯丝核菌(Rhizotonia solaniKühn)菌株,经玻片吉姆萨氏染剂(Gimsa′sstain)染色程序观察细胞核数目,全部测试菌株均属于多核。用标准菌株,通过载玻片菌丝融合实验测定,将纯化的272个菌株划归为3个菌丝融合群:AG-2、AG-4和AG-5,分别占总菌株的6.24%、84.2%和1.1%。另有23个菌株不与任何标准菌株融合,占8.46%,说明新疆北疆棉田立枯丝核菌的优势菌系是多核丝核菌的AG-4融合群。通过从10种不同配方的培养基中筛选的效果好的麦芽蛋白胨(MPDA)配方培养基(Ⅱ)进行对峙培养,以建立标准菌株,将纯化获得的272个丝核菌菌株,划分为6个不同的营养亲和群,研究说明新疆北疆地区棉田立枯丝核菌各菌丝融合群内确有不同程度的分化。

Anastomotic Group of Rhizoctonia solani from Cotton Field and Its Vegetative Compatible Group in Northern Xinjiang

399 fungal strains were isolated from ill cotton seedlings and 686 soil samples collected from northern Xinjiang using routine method.272 of them were identified as purified Rhizoctonia solani(RS) strains and they all belong to multinucleate through Giemsa's staining.They were divided into three anastomotic groups through cover glass hypha mating with standard strain: AG-2,AG-4,and AG-5,and account for 6.24%,84.2%,and 1.1% of total respectively.There were another 23 strains could not fuse with any standard strains and account for 8.4% of the total.These indicated that the dominant RS system in northern Xinjiang cotton field is AG-4 anastomotic group.In order to establish standard strain,272 purified RS strains were compared culture through 10 different formula media and screened with good effective MPDA(maltose peptone dextrose agar) formula II medium,and divided them into 6 different vegetative compatible groups.These suggested that anastomotic group of RS in Northern Xinjiang has different degree of differentiation.