1978 Volume 44 Issue 5 Pages 633-640
Gloeocercospora sorghi was recovered from 68% of sorghum seeds collected from the severely-diseased field at Ebina (Kanagawa prefecture), the emergence rate of these seeds grown in autoclaved soil was as low as 20%, and 80% of the emerged seedlings were diseased with lesions on their leaves. The fungus was recovered from stems near the ground from 2 out of 39 young seedlings originated from pathogen-free seeds and grown in the diseased soil collected from Ebina, but no fungus was recovered from seedlings grown in autoclaved soil. The conidia, which were variable in size and number of septation in media tested, germinated 100% within 4hr on water agar (WA) plates at 20-30C. Sclerotia prepared from 30-day-old culture also germinated 96%, and 22% of them formed sporodochia directly on them on WA in 4 days after seeding. The fungus might penetrate within 2hr and symptoms developed within 24hr after inoculation. Results indicate that the fungus is transmitted through infected seed, and also survives in soil with a potentiality causing infection.