Grain yield and stability of early-maturing single-cross hybrids of maize across contrasting environments

摘要

Testing and identification of high-yielding and stable hybrids adapted to contrasting environments is crucial for sustainable maize (Zea mays L.) production in sub-Saharan Africa. The objectives of this study were to (i) assess the yield response of 150 single-cross hybrids under low soil nitrogen (low-N), Srr/ga-infested and optimal growing environments, and (ii) identify the most suitable environments for the selection of superior and stable hybrids. The 150 hybrids were derived from 30 inbred parents via North Carolina design II mating scheme. They were tested, together with six checks, in a 13 x 12 alpha lattice design with two replications across 10 test environments in 2016 and 2017. Genotype by environment interaction was significant for yield, with high repeatability (0.70) across the test environments. Test environments KWDS-LN-16 and KWDS-OPT-16 were found to be the ideal test environments for selecting superior hybrids. About 62% of the hybrids were stable across environments. Hybrids TZEI 3A x TZdEI 192, TZdEI 216 x TZEI 3A and TZEI 379 x TZdEI 272 were identified as high yielding and most stable across environments. These outstanding hybrids with tolerance to both Striga and low-N should be further tested extensively on-farm for potential release in Ghana and other West African countries.