Molecular characterization of Rhizoctonia solani AG4 using PCR-RFLP of the rDNA-ITS region

Rhizoctonia solani isolates obtained from common beans (Phaseolus vulgaris L.) were included in an AG4 anastomosis group in accordance with hyphal anastomosis. In the subgrouping of AG4 isolates, PCR-RFLP patterns in the rDNA-ITS were used. After obtaining the genomic DNA belonging to R. solani AG4, an approximately 700 bp amplification product of the ITS1-5.8S-ITS2 region was obtained with PCR, using ITS1 and ITS4 universal primers. The PCR products were digested with MseI, HincII, AvaII, and MfeI restriction endonucleases, and different PCR-RFLP patterns were obtained for the AG4 HGI and AG4 HGII subgroups. In this study, in addition to the enzymes that were previously used in the AG4 subgrouping, AvaII restriction endonuclease was also seen to be effective in the subgrouping. In this way, the isolates that were grouped as R. solani AG4 according to anastomosis reactions were separated into 2 subgroups, HGI and HGII. This study indicates that the common beans in the Black Sea coastal region are more commonly infected by Rhizoctonia solani AG4 HGI.