Damping-off of Cabbage Caused by Rhizoctonia solani AG-2-1 and AG-2-2 IV

Abstract

Damping-off symptoms were observed in four commercial cabbage fields in Iwate, Japan, from May to June 2021. Four fungal isolates from the diseased plants were identified as Rhizoctonia solani anastomosis group (AG)-2-1 and AG-2-2 IV. They were confirmed as pathogens, based on the morphological traits, temperature-dependent growth characteristics, hyphal anastomosis reaction, genome analysis using specific PCR primers, rDNA-ITS sequences, and pathogenicity tests. This is the first report of damping-off on cabbage caused by R. solani AG-2-1 and AG-2-2 IV in Japan. Therefore, we propose that they are the pathogens of this disease.