Diversity Studies of Sclerotium rolfsii Sacc. Isolates Associated with Collar Rot of Soybean Through Molecular and Biochemical Approaches

Background: Sclerotium rolfsii Sacc. is one of the potential soil-borne plant pathogens due to its significant loss in terms of yield and quality in several crop plants. In soybean the pathogen is associated with collar rot disease. Methods: Sixteen samples which were showing collar rot symptoms were collected from different soybean growing regions of the country and were subjected for isolation and purification. Molecular detection was carried out using ITS1/4 primers followed by phylogenetic analysis was performed using the MEGA 11 bioinformatics tool. Further, the biochemical test was made for oxalic acid production to determine the variability across the isolate. Result: DNA was amplified for ITS rDNA region at 650-700 bp in all the sixteen isolates. BLAST detection of nucleotide sequence of sixteen isolates framed mainly into two distinct phylogenetic clusters. Cluster B consisted of two isolates (MPSe 1 and MHSa 3) whereas, Cluster A contains the remaining fourteen isolates. There was a variation with respect to oxalic acid production among the isolates which was in the rage of 1.15 to 2.23 mg/ml.