Heterosis and combining ability studies in low chill requiring SI and CMS lines of cabbage (Brassica oleracea var. capitata L.)

Abstract

The present investigation entitled “Heterosis and combining ability studies in low chill requiring SI and CMS lines in cabbage (Brassica oleracea var. capitata L.)” was carried out at Vegetable Research Farm of the Department of Vegetable Science and Floriculture, CSKHPKV Palampur. Six lines viz., SI-2008-09, I-4-6, I-4-4, M-G-7, S-G-7 and 105-III-CMS were crossed with three testers viz., KGAT-II, GAP and Glory-I to produce 18 F1s during Rabi season 2023-2024. These 18 hybrids were evaluated along with parents and one private sector commercial hybrid as standard check (WS-483) in randomized block design with three replications during Rabi season 2024-2025. RBD analysis revealed significant differences among genotypes (hybrids and parents) and the line × tester analysis also revealed significant differences for lines, testers and line × tester interaction for head yield and related traits studied. On the basis of per se performance and standard heterosis the most promising cross combinations for marketable head yield and other related traits were I-4-6 × GAP (10.87%) and I-4-6 × Glory-I (8.14%). On the basis of combining ability effects, parental lines I-4-6, M-G-7 and tester GAP were found to be the best general combiners for majority of the traits and the cross combinations S-G-7 × Glory-I and 105-III-CMS × GAP were found to be the best specific combinations. The dominant variance (σ2D) was of greater magnitude than additive variance (σ2A) for marketable head yield and most of the component traits indicating the role of non-additive gene action in exploitation of these traits, hence justifying the development of hybrids in cabbage. These newly developed hybrids were found quite promising under mid hill conditions of Himachal Pradesh. As the parents involved in the development of these hybrids are low chill requiring, hence, the seed production can be easily done in mid hill conditions.