Genetic analyses of correlated solids, flavor, and health-enhancing traitsin onion (Allium cepa L.)

Onion possesses organosulfur compounds and carbohydrates that provide uniqu e flavor and health-enhancing characteristics. Significant phenotypic corre lations have been reported among soluble solids content (SSC), total dry ma tter, pungency, and onion-induced in vitro antiplatelet activity. A genetic map and segregating F3M families derived from a cross between two inbred p opulations were used to identify and estimate the effects of quantitative t rait loci (QTLs) controlling these traits at 30 and 90 days postharvest. In vitro antiplatelet activities among different onion populations were consi stent across six human blood donors. Most of the populations showed in vitr o antiplatelet activities; however, for some donors, one of the parental li nes and two F3M families had pro-aggregatory effects under our experimental conditions. SSC, dry matter, pungency, and in vitro antiplatelet activity showed significant positive phenotypic and genetic correlations. A chromoso me region on linkage group E accounted for a significant amount of the phen otypic these traits. The correlations among these traits may be due to link age or pleiotropy of genes controlling solids content. Our results indicate that it will be difficult to develop onion populations with lower pungency and high in vitro antiplatelet activity; however, the strong genetic and p henotypic correlations between high in vitro antiplatelet activity and high SSC are beneficial for the health functionality of onion.