Genetic Analysis among Elite Nigerian Open-Pollinated Varieties and Inbred Lines of Maize (Zea mays L.) for Grain Yield and other Yield Components

Abstract

The purpose of this study was to determine the combining ability of open-pollinated maize varieties for grain yield using nine (four males and five females) parents. In the 2018 dry season, a nursery trial for the formation of an initial F1 breeding population using a line tester mating design was carried out at Lushi Irrigation Station in Bauchi. The nine parents and their resultant 20 F₁ were evaluated in a Randomized Complete Block Design (RCBD) with three replications at Bauchi and Jos during the 2019 cropping season. Significant differences were found among the genotypes studied. The combining ability analysis revealed significant differences in all traits except number of kernels per row and days to tasseling; days to silking and number of kernels per row. The findings also revealed that both additive and non-additive gene action in maize were important in controlling grain yield and other agronomic traits. For most traits, the parents TZEEI-112, TZEEI-29, TZEI-68, SAMMAZ-15, SAMMAZ-33, SAMMAZ-45, and SAMMAZ-51 have been identified as good general combiners. SAMMAZ-33 TZEI-65, SAMMAZ-15 TZEEI-112, SAMMAZ-33 TZEEI-112, and SAMMAZ-51 TZEEI-112 have also been identified as good specific combiners for kernel yield. For all traits except 300 kernel weight, number of ears per plant, and number of rows/ear, the ratio of GCA variance to SCA variance was less than one, indicating a preponderance of non-additive gene action.