Effect of azoxystrobin 4.8% w/w + chlorothalonil 40% w/w SC (Amistar opti 560w/v SC) on watermelon against downy mildew and leaf spot

Abstract

Watermelon (Citrullus lanatus) belonging to the family Cucurbitaceae is one of the most widely cultivated crops in the world. Foliar diseases of watermelon have become a major constraint in watermelon growing areas causing qualitative as well as quantitative losses. Therefore, a field experiment was carried out on the effect of Azoxystrobin 4.8% w/w + Chlorothalonil 40% w/w SC (Amistar opti 560w/v SC) against downy mildew and leaf spot during 2014-15 and 2015-16, at College of Horticulture, Hiriyur. Experimental results revealed that all the treatments significantly reduced the leaf spot and downy mildew disease severity over untreated control. Amongst all the treatments in both season significantly least disease severity of leaf spot (5.67 and 5.33%, respectively) and downy mildew (5.23 and 5.16) was recorded with foliar sprays of Azoxystrobin 4.8% w/w + Chlorothalonil 40% w/w SC at 4ml/lit and highest yield of 30.33 and 17.86 t/ha, respectively followed by Azoxystrobin 4.8% w/w + Chlorothalonil 40% w/w SC (Amistar opti 560w/v SC) at 3ml/lit.