Line × tester analysis across equatorial environments to study combining ability of Indonesian maize inbred

Selection of optimal combination in hybrid development is crucial to successful breeding program and key determining factor for generating superior variety. Knowledge of gene combination system of maize traits under equatorial environments has not been extensively studied. It is the aim of this study to assess the performance of maize inbred lines across equatorial environments in Indonesia. Twelve test crosses (MAL01 × MYL10, MR14 × MYL10, MAL01 × MYL12, MR14 × MYL12, MAL01 × MYL15, MR14 × MYL15, MAL01 × MYL16, MR14 × MYL16, MAL01 × MYL2, MR14 × MYL2, MAL01 × MYL7 and MR14 × MYL7) and three commercial hybrids (NK 33, DK979 and Bima 11) were investigated for six agronomic components in randomized complete block design across six locations in Indonesia. The results revealed that interaction of crosses versus environment was significant for grain yield, maturity and other agronomic components. The estimates of GCA exhibited that lines MYL10 (L3), MYL15 (L5) and tester MR14 (T2) were a good general combiner, hence MYL10 (L3), MYL15 (L5) and tester MR14 (T2) can be used for generating superior maize hybrid. Combined analysis of SCA effects showed that the crosses MYL 10 (L3) × MR 14 (T2) gave the highest yield of 10.73 t/ha and significantly superior to the best check DK979 (10.17). The hybrid from this cross has to be evaluated in advance to determine the prospect for release as a new commercial hybrid in Indonesia.