First report of Rhexocercosporidium panacis causing rusty root of Panax ginseng in Northeastern China.
In northeastern China, Asian ginseng (Panax ginseng) roots exhibited reddish brown lesions of various sizes, irregular shapes, and diffuse margins, typical of rusty root disease. The lesions remain superficial, smooth, and limited to the epidermal and peridermal tissues. In September 2013, ten symptomatic roots were collected from each of three fields in Jilin and Heilongjiang provinces. Based on morphological characteristics, molecular investigations (sequence analysis of the rDNA internal transcribed spacer region and β-tubulin) and pathogenicity tests, the causal agent was identified as R. panacis. This is thought to be the first report of R. panacis causing rusty root of P. ginseng.