First report of a leaf blight caused by Pyricularia pennisetigena on Cenchrus pauciflorus in China.
Cenchrus pauciflorus [C. spinifex], an annual herbaceous plant in Gramineae family, is a noxious invasive weed in China. In 2016, an unknown leaf blight was observed on C. pauciflorus in Zhangwu county, Liaoning province, China. Initial symptoms appeared as light-brown pinpoints mostly at the leaf apex, which subsequently enlarged along the veins and became oval or elongated, scattered, medium brown, with a dark brown border, greyish necrotic centres mostly, and occasionally distinct yellow halos. Based on morphological characteristics, sequence analysis and pathogenicity test, the causal agent was identified as P. pennisetigena. According to previous reports, P. pennisetigena can infect Cenchrus ciliaris in Japan, Cenchrus echinatus in the Philippines, Cenchrus echinatus, Echinochloa colona, Triticum aestivum and Panicum maximum in Brazil, and Pennisetum glaucum in the USA. This is thought to be the first report of leaf blight on C. pauciflorus caused by P. pennisetigena in China.