First report of Stagonosporopsis vannaccii causing leaf spot on Crassocephalum crepidioides in China.
Crassocephalum crepidioides, native to tropical Africa, is an important invasive weed in many countries, seriously threatening the agricultural ecosystem. In December 2018, approximately 100% of C. crepidioides plants exhibited leaf spots in the kudzu (Pueraria lobata) garden in Tianlin County, Baise City, Guangxi, China, but kudzu was not affected. Spots were small and brown, surrounded by a yellow-green halo initially, enlarged to subrotund or irregular in shape, slightly sunken, developed as a dark brown to dark spot with gray-white necrotic center, and exuded an orange droplet under humid conditions. Based on morphological characteristics, molecular data and pathogenicity, the causal agent was identified as S. vannaccii. This is thought to be the first report of S. vannaccii causing leaf spot on C. crepidioides in China.