Genotype by Trait Associations among Drought Tolerant Maize Inbred Lines

Abstract

Twelve tropical, yellow maize inbred lines identified as drought tolerant were evaluated in multi environments, including managed drought, rain fed and irrigated conditions. The objective was to study genotype-trait associations across environments. A 3 × 4 a-lattice design with two replications was used in each environment. Data were recorded for twenty-one traits. Combined analysis of variance using data from all environments was done for all traits using the GLM procedure in SAS version 9.3. Genotype by trait associations were revealed using the genotype main effect plus genotype-by-environment biplot model in GENSTAT 14th Edition. Inbred lines which were associated with high grain yield and related desirable traits such as a low drought susceptibility index under managed drought were DMR-M-81, DMR-M-88, FA6, GPM36 and M39. Across the diverse environments, DMR-M-84, DMR-M-88, FA6 and GPM36 were associated with grain yield and/or its related traits. The inbred lines associated with desirable traits could be evaluated for combining ability in order to know their desirability in cultivar development. These inbred lines could be used as female parents in seed production programmes since high productivity and drought tolerance are important qualities of female parents in seed production.