Study of southern corn leaf blight (SCLB) on maize genotypes and its effect on yield

摘要

Southern corn leaf blight is considered the most devastating disease of maize crop, which causes noticeable reduction in crop yield. Inbred lines are useful because they are genotyped, multiple time phenotyping is possible, and genetic uniformity, genetic stability and its vigor make inbred lines suitable to study in diversified environment. In present investigation, 12 maize genotypes viz: NC-2703 (hybrid), NC-2003 (hybrid), SP-3 (inbred line), NCML-73 (inbred line), NRL-6 (inbred line), NRL-4 (inbred line), Soan-3 (variety), Rakaposhi (variety), Margala (variety), EV-1097 (variety), Local-Y (variety), Local-W (variety) were tested against southern corn leaf blight under laboratory and field conditions. According to disease severity scale (0-5) inbreds SP-3 and NCML-73 were found highly resistant; Local-W moderately resistance and rest of the genotypes were least resistance in in vitro analysis. In field screening, Margala, NRL-4, EV-1097 showed maximum resistance followed by moderately resistant SP-3, NCML-73, NC-2703, NRL-6 and Local-Y maize genotypes. NC-2003, Rakaposhi and Soan-3 showed least resistance during field evaluation. Cochliobolus heterostrophus showed considerable effects on yield of crop. Significant difference was found in grain yield, plant height, ear height and ear weight while ear placement, ear per plant and infected ear data were non-significant. The results clearly showed the effect on maize genotypes and its yield.