DNA Base Sequence Homology in Rhizoctonia solani Kühn
V. Genetic Relatedness within AG-6
1984 Volume 50 Issue 3 Pages 346-352
Details
1984 Volume 50 Issue 3 Pages 346-352
DNA base sequence homology among AG-6 isolates of Rhizoctonia solani was determined by DNA-DNA reassociation kinetics. Five of 10 isolates examined shared high DNA homology ranging from 91.8 to 97.7%. This group was classified as AG-6 homogeneous group I (HG-I). DNA homology among the remaining 5 isolates was 55.4 to 66.2%. They showed only 47.5 to 62.9% DNA homology with AG-6 HG-I isolates. These isolates were designated AG-6 genotypic variation (GV) isolates. Each of them appeared to have gene structures that differed by nucleotide substitutions. The genetic divergence among AG-6 isolates was also clearly demonstrated by the electrophoretic patterns of proteins and appearances of the cultures. These results suggest that AG-6 consists of strains that are phylogenetically related but have significant genetic polymorphism.
