Management of Downy Mildew Disease of Cauliflower Seedlings in Seed Bed

  • Ram Devi Timila Plant Pathology Division Nepal Agricultural Research Council Khumaltar, Lalitpur

Abstract

Cauliflower (Brassica campestris var. botlytis L.) is an important winter vegetable of Nepal. Downy mildew (Peronospora parasitica) is one of the economically important foliar diseases causing considerable seedling loss in seed bed. An experiment was conducted in a randomized complete block design at Khumaltar using Kathmandu local variety to find out effective control measure in seed bed condtion during 1998 and 1999. Among various fungicides used such as Benlate, Rovral, Ronilan and Knlaxyl and biologcal agents, Trichoderma viride and garlic extract either as seed treatment/seed soaking or as spray on soil surface after seeding, Krilaxyl (0.2 %) (metalaxyl8% plus mancozeb 64%) spray on soil surface after seeding was found to reduce downy mildew severity in seed bed. Seed treatment and spray with Krilaxyl on soil surface controlled the downy mildew at 24.88% and 36.44% in 1998 and 10.14% and 41.68% in 1999 . Biomass of the seedlings was also found hgher in Krilaxyl treated plants with slow dsease progress compared to other treatments. Krilaxyl spray on soil surface after seeding could be used to reduce downy mildew severity in seed bed of cauliflower thereby preventing severe seedling loss.