Studies on loss assessment of maydis leaf blight (Bipolaris maydis. Nisikado) Shoemaker in maize

Abstract

A field experiment was conducted during at Main Agriculture Research Station, University of Agriculture Sciences, Dharwad to find out the losses caused by maydis leaf blight of maize in two hybrids namely 900 M and DKC 9117. Split plot design with two main treatments (900 M and DKC 9117) and three sub treatments as natural infection, artificial inoculation and protected plots was laid out.The mean avoidable losses in grain yield ranged from 11.45 to 16.64 percent in Natural and artificial inoculated plots respectively, The avoidable losses in grain yield ranged from 2.87 to 51.93 percent with a mean of 14.51 percent. The losses were directly proportional to the disease severity. The maize hybrid 900 M showed more disease severity (90.34%) in comparison to hybrid DKC 9117 (50.69%) in artificially inoculated plots. The protected plots (Propiconozole 25 EC sprayed) were free from maydis blight in both the hybrids. In the present study besides significant losses in grain yield (8.13-19%), considerable losses or reductions were also observed with other parameters like stover yield (13.25-33.93%), 100 grain weight (5.04-12.85%), shelling percentage (0.73-4.14%), volume of 100 grains (6.40-17.73%), cob length (5.61-12.54%), number of grains per row (4.14-9.65%), Cob diameter (2.10-4.74%), plant height (1.58-14.26%) in two hybrids (900 M and DKC 9117) under natural and artificial inoculated conditions.