A CRISPR/Cas9-Based Study of CgloRPCYG, a Gene That Regulates Pathogenicity, Conidial Yield, and Germination in Colletotrichum gloeosporioides

The filamentous fungus Colletotrichum gloeosporioides is the causative agent of one of the most serious diseases that damage plant fruit. In this study, we discovered and experimentally characterized a new gene in Colletotrichum gloeosporioides named CgloRPCYG. The CRISPR/Cas9 knockout mutant and complementary strain of CgloRPCYG were then obtained by polyethylene glycol (PEG)-mediated protoplast transformation to determine the related phenotypes. Compared with the wild-type strain and complementary mutant, the pathogenicity of the CRISPR/Cas9 knockout mutant was significantly decreased, the conidial yield was significantly reduced, and conidial germination was significantly delayed. These data indicate that CgloRPCYG contributes to pathogenicity, conidial yield, and germination in C. gloeosporioides. The successful application of the CRISPR/Cas9 system in C. gloeosporioides also confirms its utility in filamentous fungi for fundamental research and practical application. Furthermore, CgloRPCYG is a potential target gene for use in the development of plant protection technologies, such as spray-induced gene silencing, with the aim of controlling plant anthracnose disease caused by C. gloeosporioides.