Effect of different types of fungicides on early blight and yield of tomato.

Abstract

Early blight (Alternaria solamj is an important foliar disease of tomato in Papua New Guinea. A trial was conducted to evaluate four broad-spectrum fungicides for their efficacy on Early blight disease and yield if tomato. Plots treated with three contact curative fungicides; Chlorothalonil (Bravo, 50% EC, 0.15% a.i); Mancozeb (Dithane M-45. 80% WP. 0.16% a.i.) and Copper oxychloride (Champion copper 50% A/P, 0.10% a.i.) effectively reduced the intensity of Early blight and yielded significantly higher than ihe systemic fungicide, Benomyl (Benlate 50% WP. 0.10% a.i.) and the unprotected. Yield from Benonyl treated plots were much lower than the untreated The yield loss in unprotected plots was estimated to be 65 3% There was a positive relationship between coefficient of disease index (CODEX) and yield Thus, the highest yields were obtained where the CODEX were the lowest