棉花黄萎病菌致病型的AFLP分析

AFLP analysis of pathotype of Verticillium dahliae of cotton

选用41个棉花黄萎病菌(Verticillium dahliae)代表菌系,在温室条件下,对4个棉花品种鄂荆1号(感)、中棉所12(耐)、文-5(抗)和唐棉2号(抗)进行致病性测定,结果可将供试菌系分为落叶型与非落叶型2类。选取8对AFLP引物PCR扩增的结果中,统计带型稳定、清晰且有多态性的条带,共169条作系统聚类分析,将上述菌系分为2大类,第一类为非落叶型菌系,包括10个非落叶型菌系和1个过渡菌系;第二类为30个落叶型菌系。根据聚类分析建立树状图,发现菌系与地理来源存在一定的相关性,而依据菌系致病力强弱分类则相关关系不大。选用25对EcoRⅠ和MseⅠ引物组合,对供试的41个V.dahliae进行AFLP扩增,筛选到2对引物E64(GACTGCGTACCAATTCGAC)、M53(GATGAGTCCTGAGTAACCG)和E49(GACTGCGTACCAATTCCAG)、M65(GAT-GAGTCCTGAGTAAGAG),能分别扩增出433bp和110bp2条仅为V.dahliae非落叶型菌系独有的特异片段,可将落叶型与非落叶型菌系分开,这2条特异片段被命名为EM_(433)和EM_(110)。

In greenhouse the pathotype of 41 strains of V. dahliae were studied by inoculating the seedlings of 4 cotton dif- ferentiators, Ejing 1 (S), Zhongmiansuo 12(T),Wen-5(R) and Tangmian 2(R). Forty-one strains were clustered into 2 groups: defoliating and nondefoliating strains. System cluster analysis based on 169 polymorphic bands from results ampli- fied with 8 effective primers was used to generate a dendrogram. Forty-one strains of V. dahliae tested were clustered into 2 groups: 10 nondefoliating strains and 1 intermediate strain; 30 defoliating strains. According to dendrogram, discovered certain relevant relationship in the strains of different geographical source. Amplified fragment length polymorphism (AFLP) was performed on 41 strains of V. dahliae of cotton in search of DNA probes specilic for nondefoliating strains. Two pairs of primers (screened from 25 pairs) were used for AFLP, E64 (GACTGCGTACCAATTCGAC), M53 (GATGAGTCCTGAG- TAACCG) and E49(GACTGCGTACCAATTCAG ), M65 (GATGAGTCCTGAGTAAGAG), and yielded bands of 433 base pairs(bp) and 110 bp which were amplified only from nondefoliating strains and named EM_(443) and EM_(110), respectively.