Role of Temperature and Relative Humidity on Mycelial Growth of Alternaria alternata Infecting Brinjal

Role of temperature and relative humidity was studied on brinjal pathogen Alternaria alternata under in vitro conditions. The mycelial growth of A. alternata is very much affected by temperature. Maximum mycelial growth was observed at 25°C. A gradual decrease in mycelial growth was observed at 30°C and 35°C, where as minimum mycelium observed as 10°C. The effect of relative humidity was studied by exposing the fungus to different levels viz., 50, 60, 70, 80, 90 and 100% and incubated at 25±1°C for 7 days. Maximum mycelial growth was recorded at 100% relative humidity which was closely followed at 90.0 per cent relative humidity. Minimum mycelial growth was observed at 50% relative humidity. It can be concluded that high relative humidity favors the growth of A. alternata.