This study evaluated the effects of microbial-enriched compost tea (CT) on the conidial germination of Golovinomyces cichoracearum DC. and development of powdery mildew on melons in a time-dependent manner. In vitro conidial germination was significantly reduced by 94 % and 85 % upon treatment with Daconil (fungicide) or microbialenriched
CT, respectively, 96 h after incubation (hai). Morphological analysis under light microscopy demonstrated that conidia co-incubated with microbialenriched CT at 48 hai appeared ruptured, which contributed to higher inhibition of conidial germination, increased cell permeability and leakage of cellular contents. These observations may be explained by antibiosis. Moreover, different application time of microbial-enriched CT on melons significantly affected disease development. There was a delay in disease development by 12 days in plants treated with Daconil, microbial-enriched CT applied 24 h after inoculation and microbial-enriched CT