Exploitation of combining ability and heterotic potential of okra under the sub-mountain region of Himalayan

Abstract

Okra (Abelmoschus esculentus L. Moench) is a vital vegetable crop well-known for its nutritional and economic importance, especially in tropical and subtropical regions. Studying heterosis and combining ability in okra is crucial for improving its yield, quality, and resistance to diseases and pests. Heterosis can produce offspring with superior traits, while understanding combining ability helps identify the best parental combinations for breeding programs. Since okra is often cross-pollinated, utilizing heterosis offers significant advantages. The research was conducted from 2022 to 2024 at the Experimental Farm, Department of Vegetable Science, College of Horticulture, Dr. YS Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, India. The goal was to assess heterosis, combining ability, and gene action in okra to develop resistant cultivars with higher yields. The experimental material included an F1 population of 40 crosses derived from 10 parental lines crossed with four testers in a Line × Tester design during first week of May, 2022. These were evaluated over two years, the first week of June 2023 and 2024, along with a standard check variety, Punjab-8. Pooled data from both years were analyzed for 14 horticultural traits. The cross combinations showed higher heterotic estimates compared to heterobeltosis and standard heterosis for traits such as fruit weight and fruit yield per plant. Significant GCA effects for pod yield per plant were observed in parental lines including Kashi Pragati (40. 40.03), Kashi Satdhari (24. 37), Punjab Suhabani (14. 76), and COHF N- 9 (7. 49). Among the cross combinations for fruit yield per plant, Kashi Satdhari × Punjab Suhabani (66. 96), Kashi Pragati × Palam Komal (55. 69), COHF N- 2 × Kashi Chaman (29. 15), UHF- Okra- 4 × Varsha Uphar (25. 36), COHF N- 11 × Varsha Uphar(25. 25.35), COHF N- 1 × Palam Komal (21. 42), COHF N- 1 × Kashi Chaman (21. 22), and UHF- Okra- 2 × Punjab Suhabani (18. 18.70) showed superior and significant SCA effects. Identifying these parent lines and their hybrid combinations based on their combining ability can be important for developing high-yielding okra hybrids. Future research involving multi-location trials could further evaluate these parental lines and hybrids to replace current okra cultivars (both hybrids and varieties). Improving okra cultivars with higher yields and better quality could increase farmers’ profits, enhance food security and meet consumer demands.