Genetic variation and interrelationships among antioxidant, quality, and agronomic traits in vegetable amaranth

This investigation was aimed to evaluate 22 promising vegetable amaranth genotypes for antioxidant, leaf quality, and agronomic traits for two test seasons. The experiment was conducted to study the degree of genetic parameters, associations among different traits, and their contribution towards foliage yield. The analysis of variance for twelve traits was found highly significant. High mean, high range of variability, and high genotypic variance were observed for all the traits except content of Ca, protein, and carotenoid. Close differences between genotypic and phenotypic variances and genotypic and phenotypic coefficients of variation were observed for all the traits. High to moderate genotypic coefficients of variation and heritability coupled with high to moderate genetic advance in percent of mean was observed for all the traits. Considering all genetic parameters, selection based on Fe, Zn, Mn, ascorbic acid content, fiber content, plant height, leaves plant(-)1, diameter of stem base, and foliage yield would be effective for the improvement of vegetable amaranth. Foliage yield had a significant positive genotypic correlation with three antioxidant traits (ascorbic acid, Fe, and Mn), two leaf quality traits (protein and fiber), and three agronomic traits (plant height, leaves plant(-1), and stem base diameter). Fiber content, leaves plant(-1), plant height, and stem base diameter had high positive direct effects and Fe, Mn, and carotenoid exhibited moderate positive direct effects on foliage yield. Based on genetic interrelationships and path coefficient values, direct selection for antioxidants (Fe and Mn), fiber content, leaves plant(-1), plant height, and stem base diameter would significantly improve the foliage yield of vegetable amaranth. Selection based on protein content concomitantly required considering the Fe and Ca contents of the genotypes.