Breeding for Higher Ascorbic Acid and Mineral Nutrients in Snowball Cauliflower (Brassica oleracea var. botrytis L.)

Abstract

The components of genetic variance and gene action effects for ascorbic acid and mineral nutrient contents in snowball cauliflower lines were estimated through line × tester analysis involving 5 Ogura based CMS lines and 7 male fertile testers. The mean squares due to lines and testers were significant for ascorbic acid and mineral nutrients (Ca, Mg, Na, K, S, Fe, Mn and Zn). Ogu 103 was best performing CMS line for K (182.32 mg/100 g), S (29.48 mg/100 g), Ca (23.19 mg/100 g), Mg (13.22 mg/100 g), Zn (313.33 μg/100 g) and Mn (235.00 μg/100 g) whereas maximum ascorbic acid (81.26), Na (24.37) and Fe content (645.03 μg/100 g) was noted in Ogu 119, Ogu 13-85 and Ogu 13-01, respectively. Among the testers, Kt-18 recorded maximum value (mg/100 g) for Na (98.03), K (277.52), S (42.87), Ca (43.73) and Mg (29.44), respectively, whereas Kt-22 had highest ascorbic acid (70.84 mg/100 g) and Mn content (343.50 μg/100 g) and Sel-26 had maximum Fe (1424.93 μg/100 g) and Zn (458.70 μg/100 g) contents. The best-performing hybrids for different macro-nutrients (mg/100 g) were, Ogu 101 × Sel-26 for ascorbic acid (94.05), Ogu 103 × Sel-26 for Na (98.63), Ogu 13-01 × Sel-26 for K (300.18), Ogu 101 × Lalchowk Maghi for S (49.34), Ogu 119 × Suprimax Late for Ca (54.65), Ogu 13-85 × DB-187 for Mg (35.60). For micronutrients (μg/100 g FW), the best hybrids were Ogu 13-01 × DB-187 for Fe (1775.60), Ogu 101 × Lalchowk Maghi for Zn (642.10) and Ogu 101 × Kt-22 for Mn content (381.60). Predominance of dominance component of variance was observed for vitamin C and mineral nutrients. The traits studied had narrow differences among GCV, PCV and broad sense heritability values, suggesting low effect of environment. The variance due to general (σ2gca) and specific combining abilities (σ2sca) were highly significant indicating the importance of both additive (σ2A) as well as non-additive (σ2D) type of gene actions. However, the ratios of σ2gca/ σ2sca (<1) and σ2A/σ2D (<1) revealed the preponderance of non-additive variance for the inheritance of traits studied. The study’s results suggest the possibility of improving these traits through recurrent selection and hybridization.