Heterotic Groupings, Perse Performance and Standard Heterosis of Quality Protein Maize (Zea Mays L.) for Yield and Yield Contributor Traits Adapted at Mid Altitude of Ethiopia

Abstract

For an organized cross breeding program, information on heterotic grouping, perse performance, and commercial heterosis of newly introduced maize lines is required. Therefore, the present study was conducted to determine the heterotic group, commercial heterosis, perse and crosses mean performance of newly introduced from IITA-Nigeria and CIMMYT- Zimbabwe quality protein maize inbred lines. 36F1 progenies generated from the four testers and nine lines, and including four standard checks a total of 40 entries, and thirteen inbred lines were planted by using Alpha lattice design with three replications at Bako National Maize Research Center and Jimma Agricultural Research center in 2019/20 main cropping season. The combined analysis over the two locations showed there were significant differences at (P<0.01) or (P<0.05) between the genotypes in grain yield, and yield contributors of the studied traits. In this study, lines that showed positive SCA when crossed with tester A were assigned to the opposing heterotic group (group B), and vice versa, based on the significance of the SCA effects. This also suggests that these inbred lines could be placed in the same heterotic group as AB. From the study, L5 had the highest yield (3.6 t/ha) of the inbred lines, followed by L2 (3.13t/ha) and L7 (2.53t/ha) respectively were identified. Regarding to the crosses, Eight promising crosses, L2xT4, L3xT4, L4xT4, L5xT2, L6xT3, L7xT2, L9xT1, and L9xT4, with higher yield than the checks, were identified. For grain yield, about twelve crosses nine crosses showed positive and significant advantages over the standard check BH545 with range of (33.3% to-24.2%) were also observed. Multilocation evaluation, tryptophan and lysine content of these genotypes must be re-evaluated to confirm the findings of this study and to use in recurrent breeding program or for directly release of the promised crosses. In general, molecular based heterotic grouping is more effective in clarifying ............