COMBINING ABILITY AND HETEROSIS OF MAIZE INBRED LINES AT THE COMARCA LAGUNERA

Abstract

This work was carried out at the locations San Pedro and Torreón, Coah., México. The objective was to estimate the general combining ability (GCA) an specific combining ability (SCA) for grain yield (GY), flowering days (FD), plant height (PH) and harvest
index (HI), of six inbred lines of the Universidad Antonio Narro – Unidad Laguna corn breeding program. The inbred lines were: LAN-123R (P₁), L-AN-447 (P₂), L-AN-360PV (P₃), L-AN-130 (P₄), LAN-123 (P₅) and L-AN-388R (P₆). The Griffing method 2 design was utilized to estimate the GCA and SCA effects, on a complete randomized block design with two replications, at each location. The combined analysis showed significant differences among locations and genotypes. The diallel analysis indicated significant effects for SCA for each of the evaluated variables. The GCA was not significant for any of the evaluated variables. The crosses P₂xP₅, P₂xP₃, P₃xP₄ and P3xP6 showed the highest SCA. Both mid and high parent positive heterosis were observed.