This study involves the efficacy testing of six new generation for the management of most devastative and cosmopolitan disease of Potato i.e., Late blight caused by Phytophthora infestans (Mont.) de Bary. To identify most important weather parameter for disease spread, the relation between daily temperature, rainfall and relative humidity and late blight development scenario throughout the season was studied. The study was conducted, in two consecutive crop seasons 2015-2016 and 2016-2017. Though all the fungicides effectively reduced the disease index over the control, out of six test chemicals, combination of Iprovalicarb 5.5% + Propineb 61.25% (T6) was found to be the best with least disease (AUDPC - 728.519) progress and highest projected yield (16.96 t/ha) and BC ratio (1: 0.777). Pyraclostrobin 5% + Metiram 55% was statistically at par with T6 showing less (AUDPC - 757.037) with 16.13 t/ha projected yield and maximum BC ratio (1:0.7645). Since there are huge reports on Phytophthora showing resistance to Phenylamide fungicides (Metalaxyl), most commonly used fungicides for late blight control in India and abroad, this combination of Iprovalicarb 5.5% + Propineb 61.25% can be suggested as an alternative for blight management. Mixtures of compatible chemicals with alternative and optimum dose sprays will effectively help in reducing losses caused by diseases as well as help in increasing potato tuber yield.

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