Deciphering Genetic Architecture, Cause-and-Effect Relationships for Yield and Micronutrient Related Attributes in Pearl Millet R-lines (Restorer Lines)

Abstract

The present study evaluated thirty restorer lines of pearl millet (Pennisetum glaucum (L.) R. Br.) to assess genetic variability, examine trait interrelationships through correlation analysis, and determine the direct and indirect effects of ten yield-contributing traits on grain yield through path coefficient analysis. Analysis of variance revealed highly significant differences among genotypes for all eleven traits, indicating substantial variability. High genotypic and phenotypic coefficients of variation, together with high broad-sense heritability [h2(b.s.)] and high genetic advance as a percentage of the mean, were recorded for grain yield per plant, grain zinc content, grain iron content, ear head length, number of effective tillers per plant, grain protein content, ear head girth, and 1000-grain weight. Grain yield per plant recorded 95.60% heritability and 103.52% genetic advance as a percentage of the mean. These estimates indicate that selection may be effective because inheritance is largely associated with additive gene action. Correlation analysis showed that ear head girth, 1000-grain weight, ear head length, and number of effective tillers per plant were significantly and positively associated with grain yield per plant. Genotypic path analysis further indicated that ear head girth, plant height, and number of effective tillers per plant had the largest positive direct effects on grain yield. Accordingly, simultaneous consideration of these traits may support the selection of higher-yielding pearl millet restorer lines.