The response of some genotypes of maize to downy mildew, maydis leaf blight, leaf rust, and stalk rot

Abstract

Plant diseases in maize are still one of the limiting factors in efforts to increase maize production. The aims of this study were: (1) to obtain populations, lines, and candidate hybrid varieties that were resistant to downy mildew (Peronosclerospora spp.), maydis leaf blight (Bipolaris maydis), rust (Puccinia sp.), and bacterial stalk rot (Dikeya sp.); (2) to identify the causative pathogen using 16s rDNA analysis. In this study, a number of lines/populations of candidate varieties were tested against downy mildew, maydis leaf blight, rust, and stalk rot. The test results showed that all tested hybrid candidates showed resistance to downy mildew even JHD 03 showed a very resistant reaction. The average downy mildew attack ranged from 0.0-10.7%. All of the hybrid candidates tested showed a moderately resistant reaction to maydis leaf blight with an average attack percentage ranging from 18.0-24.7%. All tested hybrid candidates showed a sensitive to very sensitive reaction to rust disease with an average attack percentage ranging from 31.3-68.7%. There were five hybrid maize lines showing very resistant to moderately resistant to bacterial stem rot disease with an average attack percentage ranging from 4.67-24%.