Genetic variability and association pattern among quantitative nutritional traits in Swiss chard (Beta vulgaris subsp. L. var. cicla) accessions and its implication for breeding

In addition to improving agronomic traits, enriched cultivar such as nutritional elements and health promoting compounds are new demands for today's and the future's perspectives of crop breeding. In this respect, among leafy vegetables Swiss chard is a good source of nutritional elements and supplies large amounts of health promoting compounds. The existing knowledge of genetic variability for mineral composition both at the phenotype and genotype level, heritability of characters and also relationships among investigated minerals is fundamental for variety selection in Swiss chard. This also applies for the assurance of desirable agronomic traits with optimum mineral concentrations. This research analysis of variance indicated highly significant differences among Swiss chard accessions for all investigated mineral concentrations and the accessions display higher phenotype coefficient variation than genotype coefficient variation for all traits. The results revealed that phosphorus, magnesium, sodium, iron, copper, zinc, manganese, nitrate and nitrite exhibited high genetic advance accompanied with high heritability (>60%). The remaining mineral content demonstrated high heritability with moderate genetic advance. Genotype correlations were higher than the phenotype correlation for significant mineral concentrations. Genotype and phenotype correlations followed similar trends in all significant cases indicating the high heritable nature of the characters and the results showed that Swiss chard accessions should allow for the selection of individuals for enriched mineral concentration in edible parts of the plant. nema