Evaluation of new generations of maize streak virus (msv) resistant varieties for grain yield, agronomic potential and adaptation to a southern guinea savanna ecology of Nigeria
Five new generations of maize streak virus (MSV) resistant varieties were evaluated along with two checks in replicated trials and for two years in a southern guinea savanna ecology of Nigeria, which is an endemic zone for the disease. Difference in grain yield between favourable growing season in 2002 and unfavourable season in 2001 was 1.68 t/ha-1, representing 30.2% yield increase of 2001 performance. Results further showed that while both rust and streak diseases appeared to have been put in check, the genotypes showed slight susceptibility to leaf blight and curvularia leaf spot, ranging from 5-7 and 4-8 percent (%) respectively. Genotypic differences were significant for grain yield, agronomic traits as well as incidences of leaf blight and curvularia leaf spot. Acr 91 Suwan-1- SR C1 was the most productive of new generations of MSV resistant varieties, having yielded significantly higher than OPV check by 32 percent (%) and comparable with the hybrid check for grain yield. The variety could therefore serve as replacement to existing cultivar and also as source of genes for future maize breeding activities in the development of superior maize varieties for the southern guinea savanna ecology.
Key words: Genotypes, grain yield, leaf diseases, adaptation.