Genotype x environment interactions in a 10 × 10 diallel cross of quality protein maize (Zea mays L.)

Abstract

A 10×10 diallel cross experiment involving white modified opaque-2 maize inbred lines was grown at four sites. A stability analysis, based on both a combining ability and a heterotic pattern model, was developed. The stability analysis provided valuable information on the genotype x environment interaction properties of the 10 inbred lines. The Gail & Simon (1985) test for qualitative interactions provided a means of determining the nature of these interactions. The inbred, SO507W(M), is shown to have the best potential for use in a hybrid breeding programme, in terms of having the highest weighted general combining ability and line heterosis, and the best general adaptability to all four sites. The single cross, SO713W(P) x PO558W(F), has been identified as one of the genotypes to be used in a recurrent selection programme that favours specific combining ability.