Identification, diversity analysis and control of the pathogens causing Ceratocystis wilt of Camphora officinarum in Southern China

BACKGROUND: Camphora officinarum Nees (camphor tree) is an economically and ornamentally important native tree species in China. In recent years, a destructive wilt disease characterized by leaf desiccation, xylem discoloration and tree death has threatened the camphor populations, especially ancient camphor resources, in several southern provinces, yet its causal agents remain unclear. RESULTS: In this study, the samples of diseased plants from Anhui, Jiangxi, Hunan and Guangxi province were collected and 46 fungal isolates belonging to four morphological types were obtained. Pathogenicity tests confirmed that 12 representatives of dominate type (29 isolates) colonized vascular tissues of camphor seedlings and reproduced field disease symptoms. Based on the formation of long-necked globose perithecia and helmet-shaped ascospores among 19 isolates, the pathogens were identified as members of genus Ceratocystis. The mating-type and phylogenetic analysis determined that 29 isolates were self-sterility or self-fertility Ceratocystis fimbriata, Ce. manginecans and Ce. eucalypticola. Cross-pathogenicity tests further confirmed their potential to infect other Cinnamomum spp. In addition, owing to the conserved 198E residue in β-tubulin, three species of Cerarocystis were sensitive to benomyl. CONCLUSION: These results provide the first comprehensive characterization of the pathogens causing Ceratocystis wilt of camphor trees in southern China, revealing diversity in species, morphology, mating types, hosts and virulence. The benomyl sensitivity of Ceratocystis spp., offers an effective strategy for disease management. © 2026 Society of Chemical Industry.