Dose optimization and field efficacy of OSBPI fungicide fluoxapiprolin against late blight disease of tomato under field conditions

AbstractPhytophthora infestans, incitant of late blight disease, is one of the most notorious and devastating pathogens of tomatoes. The present study was undertaken during two consecutive rabi seasons of year 2018-19 and 2019-20 to assess the efficacy of new fungicide belonging to the oxysterol binding protein homologue inhibition (OSBPI) group, fluoxapiprolin (15, 20 and 25 g ai ha-1) in comparison with azoxystrobin 125 g ai ha-1, mancozeb 1500 g ai ha-1 and famoxadone + cymoxanil 85+115 g ai ha-1against late blight of tomato. Results from two year field experiment indicated that three foliar applications of fluoxapiprolin 20 g ai ha-1 at 10 days intervals were highly effective when applied as soon as the first symptoms of the late blight appear. The treatment fluoxapiprolin 20 g ai ha-1 provided 77.6 and 75.6% disease control during 2018-19 and 2019-20, respectively. Fluoxapiprolin 20 g ai ha-1 provided 48.8 and 63.2% yield gain over untreated check in 2018-19 and 2019-20, respectively.