ECONOMIZED WATER VOLUME AND CONCENTRATION OF FUNGICIDE FOR MANAGEMENT OF LATE BLIGHT OF POTATO IN SUBTROPICAL PLAINS OF INDIA

Abstract

The late blight disease caused by Phytophthora infestans (Mont) de Bary, is one of the most devastating disease of potato. Fungicides are indispensable for quick and effective management of late blight disease of potato. Economizing water volume and concentration of fungicides along with proper coverage of foliage are most important aspects for successful management of late blight disease. Most commonly, fungicide mancozeb 75 % WP was evaluated at four doses in different water volume during three consecutive years (2017-20). The results revealed that mancozeb @ 0.5 % (2.5 kg/500 L water/ha) had least average disease severity (25.28 %), followed by mancozeb @ 0.4 % (2.0 kg/500 L water/ha, 26.50 %) and mancozeb @ 0.3 % (1.5 kg/500 L water/ha, 26.33 %) against of 96.39 % in control. These treatments were found statistically at par with each other. The highest average tuber yield (34.35 t/ha) and B: C ratio (2.80) was recorded when mancozeb applied @ 0.5 % (2.5 kg/500 L water/ha) against tuber yield 28.14 t/ha & B:C ratio of 2.42 in control. It can be concluded that concentration of fungicides have much more importance along with proper coverage of plant foliage. Hence, the water volume of 500 L/ha is sufficient with battery operated knapsack sprayer.