Selection of drought-tolerant tef (Eragrostis tef) genotypes using drought tolerance indices

Drought stress is one of the major abiotic constraints affecting production and productivity of tef (Eragrostis tef). Genetic resources and selection methodologies are among the prerequisites to improve the efficiency of breeding for drought tolerance. The objectives of this study were to determine the principal selection indices and to identify promising genetic resources of tef for drought tolerance breeding. A total of 144 tef genotypes were evaluated using a simple lattice design with two replications. Genotypes showed highly significant (p ≤ 0.01) differences for 10 drought tolerance indices. Principal component and correlation analyses revealed mean productivity, harmonic mean, geometric mean productivity and stress tolerance index as the principal indices highly correlated with grain yield in the stressed and non-stressed environments, indicating their suitability for identifying superior tef genotypes. Genotypes 215678 (g25) and Dschanger (g133) were adaptable to both stressed and non-stressed environments, which could be useful for drought stress tolerance breeding. Genotypes DZ-Cr-387 (g1), 9403 (g4), 205896 (g48) and 9415 (g122) were selected for their higher grain yield under the non-stressed condition. Genotypes DZ-Cr-385 (g22) and DZ-Cr-37 (g28) were selected for their lower yield reduction under moisture stress, intermediate grain yield performance in the non-stressed environment and high grain yield potential in the moisture-stressed environment.