Introgression of Temperate Material to Improve Grain Yield in a Tropical Maize Population

The effect of introgression of the temperate maize population BUGARD on the grain yield of a low-yielding tropical maize population well appreciated for the quality of its grains, NCP80, was studied. NCP80 was crossed with BUGARD to obtain the F1. The BC1 obtained by backcrossing the F1 to NCP80 was random mated thrice. The tropical parent NCP80 and the BC1 (NBN) were evaluated in two tropical locations using a randomized complete block design with three replications. Introgression of the temperate population BUGARD into the tropical population NCP80 significantly increased grain yield. The resulting population, NBN, appeared, moreover, significantly earlier than NCP80 and not significantly different from it for resistance to rust, tropical blight and maize streak, ear height, husk cover and harvest index. NBN may, further, be improved for resistance to maize streak and grain yield by recurrent selection.