Management of seedling blight disease in black pepper (Piper nigrum L.) nursery

Abstract

Seedling blight of black pepper (Phytophthora capsici) is the major disease in black pepper nursery. Three antagonists, Trichoderma harzianum, Pseudomonas fluorescens and Bacillus subtilis, chemical fungicides mancozeb (75 WP) and copper oxychloride (50WP) 0.1%, 0.2%and 0.3%, metalaxyl (35WS), carbendazim(50WP), propiconazole (25EC), azoxystrobin (23SC) and carbendazim 12% + mancozeb 63% (75WP) 0.05%0.1%, and 0.2%, tebuconazole50%+ trifloxystrobin 25% (75 WG) 0.02%, 0.04% and 0.06% and metalaxyl 8%+ mancozeb 64% (72 WP) 0. 2%, 0. 4% and 0. 6% and organic preparations neemazal and garlic extract at 0.1%, 0.2% and 0.3% and ready to use neem oil garlic soap at 1%, 2% and 3% were evaluated under in vitro conditions. T. harzianum and P. fluorescens produced inhibition 55.56% and 53.33% respectively. The chemical fungicides metalaxyl 8%+ mancozeb 64% (72 WP) at 0.6% and copper oxychloride (50WP) at 0.3% shows 100% inhibition of growth of the pathogen and garlic extract at 0.3% and ready to use neem oil garlic soap at 3% shows 28.88% and 31.11% inhibition of growth of the pathogen under in vitro conditions. These effective treatments were selected for the pot culture study. The pot culture study shows that percent disease index is minimum in case of metalaxyl 8%+ mancozeb 64% (72 WP) at 0.6% treated black pepper seedlings compared with other treatments.