Heterosis and combining ability of seven yellow maize populations in Nepal - Mexico, DF (Mexico) CIMMYT : 2004 - p. 148-155 - Printed
Seven yellow maize populations were crossed in 7 X 7 diallel mating system during winter 1999. The parents and their crosses were evaluated at four locations during summer 2000 with objectives to determine heterosis, heterotic populations, and combining ability. Data were recorded for days to silk, plant height, ear height, and grain yield. Percent heterosis for all the traits was calculated over the better parent values. Analysis III as suggested by Gardner and Eberhart (1966) was used to obtain estimates of GCA and SCA. The overall mean grain yield for parents and their crosses was 5262 and 6069 kg/ha, respectively. Among the parents, Hill Pool Yellow produced the highest grain yield (6430 kg/ha) followed by Rampur Composite (6042 kg/ha). High-parent heterosis for grain yield ranged from -17.8 to 23.9%. Non-significant G x E interaction for grain yield was recorded. Highly significant difference for grain yield was observed for entries and parents but significant for parents vs. crosses, crosses and SCA. GCA effects were found non-significant for yield. Upahar with Arun 4, Rampur Composite and Khumal Yellow; Hill Pool Yellow with Khumal Yellow, Arun 2 and Arun 4; Arun 2 with Rampur Composite and Rampur 2;and Arun 4 with Rampur 2 are the possible heterotic partners for the evaluated populations. Reduced days to silk, plant and ear heights were observed for crosses compared to their either parents.