Avaliação dialélica de linhagens elite e híbridos de milho

Abstract

Current investigation generated genetic information related to maize production. The general combining ability (GCA) of twelve maize elite inbred lines and the specific combining ability (SCA) of all possible 66 single hybrids obtained from those parents were estimated according to Griffing's methodology's second model (1956). A randomized block design was applied in four experiments with three replications. The evaluated traits were grain yield, plant and ear height, a 1000 grain weight, number of kernel rows per ear and number of kernels per row. After performing the individual analysis of variance and checking the homogeneity of residuals for each trait, a joint analysis of variance was undertaken. The sum of squares of treatments was subdivided into sum of squares of parents, of F1 and parents x F1. Application of the Scott and Knott test at 5% probability level classified mean grouping of grain yield of hybrids (SF076 x PD620, HD128 x PD620, PD620 x PD391, PD391 x PF128 and HD128xSF241) within the first group in all environments under analysis. Diallel analysis identified three strains with a high GCA ability for grain yield (SF241, PD620 and PD391) and three hybrids with a remarkable SCA for the same trait (HD128 x SF241, HD128 x SD462 and HD128 x PF771). Strains PD620, PD391 and SF241 were the most promising with the improvement program.