Genome-wide association analysis revealed genetic markers linked to grain yield and yield related traits in finger millet [Eleusine coracana (L.) Gaertn] grown in acidic soils

Aim Finger millet is a nutritionally rich crop cultivated in the arid and semi-arid regions of Africa and Asia. Soil acidity has a major impact on the crop’s yield and productivity as tolerant cultivars that perform well in acidic soils are limited. This study aimed at evaluating major finger millet phenotypic traits under acidic soils followed by identifying associated markers. Method A total of 288 finger millet genotypes were field evaluated for 8 major phenotypic traits including grain yield under acid soil conditions at Bako and Gute field sites in Ethiopia. In addition, the same genotypes were subjected to genotyping-by-sequencing to generate single nucleotide polymorphism markers to analyze association mapping. Results Data analysis revealed significant phenotypic variation in all targeted traits among the studied genotypes. Genotypes Ec-100093 (322.7 g), Ec-215803 (310.2 g), and Ec-203322 (301.2 g) were relatively high-yielding, whereas genotypes Ec-229721 (31 g) and Ec-242110 (31.2 g) had the lowest grain yield across the two locations. The broad-sense heritability of the traits ranged from 0.04 for the number of effective tillers (NET) to 0.78 for days to emergence (GY). The marker-trait association analysis using Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway model revealed 23 SNP markers significantly associated with one or more traits. Among the273 significant markers, one associated with days to emergence, seven with days to heading, four with days to maturity, three with grain yield (GY), two with ear length, one with plant height, two with number of fingers, and three with the number of effective tillers (NET). Conclusions Once validated with further research, the identified novel markers associated with the targeted traits will potentially be useful for genomics-driven finger millet improvement.