Effect of environmental factors on the conidial germination of Peronospom alia causing downy mildew of blond psyllium

摘要

Influence of environmental factors on conidial germination ofPeronospora alta, a downy mildew pathogen of blond psyllium was investigated. Maximum germination of conidia was recorded at 15 deg C, 100 % relative humidity, pH 7, diffused natural light,tap water, exposure to near ultra violet light for 20 minutes. Germination was highest in conidia produced in first generation. Increased number of washing caused corresponding decrease in germination. Conidial collection at 6 h gave maximum germination.