Genome-wide association analysis revealed genetic markers linked to grain yield and yield related traits in finger millet grown in acidic soils

Aim

Soil acidity has a major impact on the finger millet 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 two independent locations (Bako and Gute) in Ethiopia. In parallel, the same genotypes were subjected to genotyping-by-sequencing to generate single nucleotide polymorphism markers to be used in the association panel.

Results

Phenotypic data analysis revealed significant phenotypic variation in all the targeted traits among the studied genotypes. Genotypes Ec-100093, Ec-215803, and Ec-203322 were relatively high-yielding, whereas genotypes Ec-229721 and Ec-242110 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 (DE). The marker-trait association analysis revealed 23 SNP markers significantly associated with one or more traits. Among the 23 significant markers, one marker associated with DE, seven with days to heading (DH), four with days to maturity (DM), one with plant height (PH), two with number of fingers, two with ear length (EL), three with the number of effective tillers (NET) and three with grain yield (GY).

Conclusions

The identified novel markers associated with the targeted traits will potentially be useful for genomics-driven finger millet improvement in acidic soils.