Evaluation of the effect of different fungicides against Phytophthora infestans (Mont) de Bary (In vitro)

Late blight of potato caused by Phytophthora infestans (Mont.) de Bary is one of the the most serious disease of potato. Several management practices have been adopted for so for to minimize the disease. Butin the present investigation based on Laboratory condition. The efficacy of six different fungicides tested on mycelial growth of the Phytophthora infestans (Mont.) de Bary that minimum radial growth with 0.75 mm in diameter was recorded at 300 ppm concentration which was followed by 200 ppm, and 100ppm and 50 ppm. However, nomycelial growth recorded at 400 ppm. As per concern of percent inhibition the highest with 100 % inhibition was recorded from 400 PPM concentration of Metalaxyl. . Hence, the use of fungicides is the very effective method for management of plant disease and continuous use both systemic and even protective fungicides of fungicides may supressed growth of a develop strain of the Phytophthora infestans (Mont.) de Bary.