First report of Rhizoctonia solani AG-1 IC causing head rot of cabbage in Japan.
n the summer of 2015, mature cabbage (Brassica oleracea var. capitata) plants showing head rot symptoms were found in Hokkaido, the northernmost island of Japan. Diseased plants had wet decay at the base of the outer leaves. Lesions then expanded to cover the entire head. Approximately 10% of plants were affected. The causal pathogen was isolated and identified as Thanatephorus cucumeris AG-1 IC based on morphological, molecular and pathogenicity analyses. This is thought to be the first report of T. cucumeris AG-1 IC causing head rot of cabbage in Japan.