新疆棉花枯萎病菌营养体亲和性的初步研究

Vegetative Compatibility of Fusarium Oxysporum from Tissue and Rhizoasphere Soil of Cotton Plants in Xinjiang [WT4 BZ]

将分离自新疆５个不同地点的棉病株或棉田土的７个菌株经单孢分离得到１８个单孢株，经鉴定均为尖孢镰孢。７个菌株的１８个单孢株分别在ＫＰＳ培养基上诱得数量不等的ｎｉｔ突变体，将它们分别与两个采自老病区莎车的棉枯萎病菌株进行营养体配对试验，结果显示７个菌株分别归属２个营养亲和群（ＶＣＧ），其中与莎车菌株明显亲和，属Ｖ１的６个菌株与莎车菌株应同属于尖孢镰孢萎蔫专化型。同一菌株的不同单孢株与莎车菌株的ＣＩ不同，反映了各单孢株所产ｎｉｔ突变体的突变类型的差异；而不同菌株与莎车菌株的ＣＩ不同则在一定程度上体现了遗传上的差异。另营养体亲和产生的亲和带形态，不同菌株有差异。

Eighteen single spored cultures of 7 Fusarium oxysporum isolates were isolates from wilt tissue and rhizosphere soil at five sites in Xinjiang and were classified on the basis of morphology.Nitrate nonutilizing(nit)mutants of each single spored cultures were produced on the medium KPS.The vegetative compatibility test,between them and the two testers(nitM and nit8 mutants of F.oxysporm from shache,an old cotton wilt area in Xinjiang) showed that 7 isolates belong in two vegetative compatibility gruops(VCG),V1 and V2 respectively. Six isolates of V1 all formed distinctive heterokaryons with the testers,they should belong to the same forma specialist f.sp vasinfectum. The compatibility index (CI) of each single spored cultures of the same isolates with the testers varied,perhaps because of defferences of the nit mutan phenotypes produced by each single spored individual of one isolate. The differences of C1 among each isolate with the tester might indicate genetic divercity to a certain extent.The morphological characters of vegetative compatibility zone among different compatible isolate pairs were different and stable.