Studies on the development of double haploids in cabbage brassica oleracea var capitata

Abstract

The present investigation entitled quotStudies on the development of double haploids in cabbage (Brassica oleracea var. capitata L.)quot was carried out in Tissue Culture Laboratory and at Vegetable Research Farm of the Department of Vegetable Science and Floriculture, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur during 2021 to 2024 with the objectives to standardize the protocol for induction of double haploidy through anther culture in cabbage, to standardize the technique for hardening/field survival of androgenic grown cabbage plants and to evaluate androgenic regenerants for their ploidy level. The experiment on callus induction revealed that genotype P1 (I-4-3 × E-1-1-2) exhibited superior androgenic potential when anthers collected from plants grown under protected conditions (E2) and inoculated on MS medium (M1) supplemented with H8 hormonal combination (2,4-D 1.5 mg/l + NAA 0.5 mg/l), showing the highest callus induction frequency and maximum callus weight. In contrast, B5 medium (M2) with the same factors was most effective for reducing days to callus induction. For shoot regeneration, B5 medium (M2) + C6 hormonal combination (BAP 1 mg/l + Kinetin 1 mg/l + NAA 0.25 mg/l) proved optimal. P1 recorded the highest number of roots per shoot, while P2 (SI 2008-09 × G-7) showed maximum root induction frequency on ½-strength B5 medium (M2) with IBA 0.2 mg/l (R3). P1 also had better survival during acclimatization. Colchicine treatment successfully induced chromosome doubling, though post-hardening survival was moderate. Two true double haploid lines were confirmed through morphology and flow cytometry. This study provides a comprehensive and optimized protocol for DH production in cabbage, highlighting its potential for accelerating pure line development and hybrid breeding in Brassica crops. The findings serve as a foundation for future work involving microspore culture, molecular marker integration and large-scale DH production systems newline