First report of black root rot disease on Morinda officinalis caused by Lasiodiplodia pseudotheobromae in China.
Morinda officinalis is a wildly cultivated medicinal plant in Zhaoqing, Guangdong Province of China. The annual production of M. officinalis in Deqin county of Zhaoqing accounts for 90% of China's total production. In 2018, a disease on M. officinalis caused significant economic losses by affecting medicinal plant quality. Symptomatic plants exhibited blackened necrotic discoloration of roots. A diseased plant was collected in June 2018 from Zhaoqing, Guangdong, for pathogen isolation and identification. Based on morphological characteristics, DNA sequencing and pathogenicity, the causal agent was identified as Lasiodiplodia pseudotheobromae. This is thought to be the first report of L. pseudotheobromae causing black root rot of M. officinalis in China.