Effect of Nutritional and Environmental Conditions on Growth of Colletotrichum gloeosporioides Causing Anthracnose of Anthurium

Isolates of Collectotrichum gloeosporioides causing anthracnose disease of anthurium were collected from five different locations of anthurium growing areas of Tamil Nadu and Kerala and their pathogenicity was established. Effect of different pH level, light intensity, media and carbon and nitrogen sources were tested against the growth of C. gloeosporioides under in vitro conditions. The results of experiment indicated that the growth of C. gloeosporioides was maximum in pH range of 6.0-6.5. The exposure of the fungus to alternate cycles of 12 hour light and 12 hour darkness resulted in the maximum mycelial growth of C. gloeosporioides compared to continuous light and darkness. Among the different media tested, potato dextrose agar medium increased the growth of mycelium followed by oatmeal agar. The maximum growth of C. gloeosporioides was observed in mannitol followed by starch and maltose as carbon source. Among the nitrogen sources, potassium nitrate was found by more mycelial growth of C. gloeosporioides.