Dynamics of oval and falcate conidium production of Colletotrichum graminicola from sorghum

Six sorghum isolates of Colletotrichum graminicola from Mali and Burkina Faso in West Africa produced in 7 days as much as 21 × 104 and 25 × 104 falcate conidia/mm2 of medium on potato dextrose agar and oatmeal agar, respectively. No oval conidia were observed in both solid media. Within 2 days 1.3 × 106 and 2.8 × 106 oval conidia/ml were detected in modified Fries' liquid medium and potato dextrose broth, respectively. As detection of oval conidia declined in potato dextrose broth at 4–6 days falcate conidium production was initiated, and at 10 days between 1.9 × 106 and 4.6 × 106 falcate conidia/ml were detected. Conidial dimorphism was not observed in Fries' liquid medium.