Study of Intraspecific variation of anastomosis group AG-2 of Rhizoctonia solani isolated from lawn (Lolium perene L.) using pectic zymorgan marker

The species of Rhizoctonia solani is one of the most diverse and complex species that morphologically is similar to Basidiomycetous imperfect fungi. Its broad range and the lack of diagnostic characters create difficulties in the study of taxonomy and population genetics of this fungus. In this study zymogram of pectinase was used as a molecular marker to determine genetic variation of R. solani AG-2 which is known as the cause of brown patch of lawn disease. In this regard 252 out of 256 isolates recovered from lawn were identified as R. solani AG-2, based on the number of nuclei per cell and anastomosis reaction. In pectic zymogram analysis of the isolates tested two loci, one for polygalacturonase and the second for pectinestrase were identified. Based on polymorphisims in these two loci, ten zymogram patterns were distinguished for 252 isolates tested. It seems not only this technique is a fast and reliable method to identify anastomosis groups of R. solani but also it could employed to study intraspecific variation of this fungus.