First report of Pythium sylvaticum causing corn root rot in northeastern China.
In recent years, poor stands of corn seedlings have occurred frequently in northeastern China, causing significant economic loss. Mature plants were stunted, the roots were necrotic, and some plants collapsed. Soil samples were collected from five fields with a history of poor stands of corn seedlings in the Heilongjiang province of China in October 2017. After being planted in the collected soil for 12 days, corn seedlings were uprooted. The pathogen was then isolated for identification. Based on morphological characteristics, molecular data (sequence analysis of the cytochrome c oxidase subunit II (COII) gene rDNA ITS) and pathogenicity tests, the causal agent was identified as Pythium sylvaticum. This is thought to be the first report of P. sylvaticum on corn in China.