Improved method to induce sporulation of Colletotrichum gloeosporioides, causal fungus of grape ripe rot

摘要

Colletotrichum gloeosporioides and C. acutatum are causal agents of grape ripe rot, but with available methods, sporulation of C. gloeosporioides on plate media has been unstable and inferior to that of C. acutatum. To facilitate studies on C. gloeosporioides, I developed an improved method to induce conidiation of this fungus. Isolates of C. gloeosporioides were pre-cultured in potato dextrose broth for 1week, then pulverized in whole broth. The homogenate was then spread on diluted oatmeal agar (15-20% commercial oatmeal agar medium, 1.5% agar) plates. After the plates were cultured at 25 degree C under continuous light for another week, the C. gloeosporioides isolates sporulated stably on the plate medium.