Ohio State University (US); National Agricultural Research Organization (NARO), Makerere University (Uganda); CIMMYT
R. Pratt, P. Lipps (US); G. Bigirwa, D. Kyetere, E. Adipala, S.Kyamanywa (Uganda); K. Pixley (CIMMYT)
Screening of mid-altitude germplasm across two seasons was completed and accessions resistant to Cercospora zeae-maydis were identified. Rind puncture resistance was evaluated to allow selection of germplasm with rigid stalks. The first testcross evaluation of gray leaf spot (GLS) resistant tropical breeding lines from the OSU program was performed in Ohio, and has been planted in Uganda. Several lines exhibit high levels of resistance to GLS and have acceptable stalk strength. A survey of farmer's fields in several districts of Uganda was completed. It was established that gray leaf spot occurrence is widespread, even during an unfavorable drought season. The survey findings establish gray leaf spot as one of the leading economic pathogens of maize in Uganda. Research has been initiated to identify genes for resistance to gray leaf spot in African maize germplasm. Polymorhpic simple sequence repeat (SSR) molecular markers have been identified and will be used to ascertain quantitative trait loci associated with resistance to Cercospora zeae-maydis.