Combining ability and gene action analysis for various biochemical traits in ornamental kale (Brassica oleraceaL. var. acephala DC.)

The present study investigated of general combing ability of the parents and specific combining ability of hybrids and gene action for biochemical traits of Ornamental kale (Brassica oleracea var. acephala) using three cytoplasmic male sterile (CMS) lines and ten doubled haploid (DH) testers in a Line × Tester mating design to elucidate the genetic control of key biochemical traits related to pigment concentration and antioxidant capacity. Thirty F₁ hybrids, along with parents, were evaluated for chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, phenol, lycopene, ascorbic acid, and antioxidant activity (CUPRAC, FRAP) and ascorbic acid. Analysis of variance revealed highly significant differences among genotypes, indicating substantial genetic variability and strong potential for improvement. Significant line × tester interactions for most traits indicated the predominance of non-additive gene action. Mean performance identified CMS-3 × KTDH-55, CMS-1 × KTDH-56, and CMS-2 × KTDH-13 as superior hybrids for multiple biochemical attributes. GCA effects indicated CMS-1, KTDH-56, and KTDH-13 as promising general combiners for pigment and antioxidant traits, demonstrating the involvement of additive gene action. In contrast, several hybrids such as CMS-1 × KTDH-56, CMS-3 × KTDH-55, CMS-2 × KTDH-13, and CMS-1 × KTDH-29 exhibited high and positive SCA effects, confirming the influence of non-additive gene effects. Overall, the study highlights the effectiveness of CMS- and DH-based heterosis breeding for enhancing pigment concentration, biochemical quality, and antioxidant potential in ornamental kale. These findings provide valuable parental combinations and genetic insights for developing high-quality ornamental kale hybrids with improved aesthetic and nutritional properties.