Study On Genetic Differentiation Of Verticillium Dahliae Isolates Of Cotton Based On AFLP

Amplified fragment length polymorphism (AFLP) was performed on 41 strains of V. dahliae of cotton from different areas of China and 11 strains of V. albo-atrum of cotton from America. The main results as follow:1. The steady AFLP-PCR system and program were established with the 41 strains of V. dahliae's DNA and 11 strains of V. albo-atrum's DNA used as templates.2. Twelve pairs of primers of EcoRI/ Msel were selected from 64 pairs of primers. 41 strains of V. dahliae and 11 strains of V. albo-atrum were amplified with the 12 pairs of primers. A specific band of 217bp, named as EM217, was amplified only from V. albo-atrum strains by using the primer of EosMog. The specific band EM217 could be used for identifying V. albo-atrum.3. Cluster analysis based on 785 polymorphic bands from results amplified with 12 effective primers to generate a dendrogram. 52 strains were clustered into 2 groups: 41 strains of V. dahliae and 11 strains of V. albo-atrum. According to the dendrogram, the molecular polymorphism had evident corralation with pathotype of strains, had certain relationship with geographic origins of the strains, but not with the pathogenicities of the strains.