Exploitation of heterosis and combining ability potential for improvement in okra (Abelmoschus esculentus L.)

Abstract

Abstract Okra (Abelmoschus esculentus L. Moench) is a vital vegetable crop known for its nutritional and economic significance, especially in tropical and subtropical regions. Studying heterosis and combining ability in okra is crucial for enhancing its yield, quality, and resistance to pests and diseases. Heterosis can lead to superior offspring with enhanced traits while understanding combining ability helps in identifying the best parent combinations for breeding programs. Okra is an often cross-pollinated crop; therefore, exploiting heterosis is advantageous. The study was conducted from 2021 to 2022 at the Experimental Farm and Quality Analysis Laboratory, Department of Vegetable Science, College of Horticulture, Dr Yashwant Singh Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, India to evaluate the heterosis and combining ability in okra to facilitate the development of high-yielding, resilient cultivars. The experimental material consisted of an F1 population of 30 crosses obtained from 10 parental lines crossed with three testers in a Line × Tester mating design, plus a standard check (Punjab-8). Estimates of heterosis (heterobeltiosis and standard heterosis) of the cross combinations UHFO-6 × Pusa Bhindi-5, UHFO-6 × Arka Anamika and UHFO-9 × Arka Anamika were high for inter-nodal distance, number of pods per plant, average pod weight, pod yield per plant, harvest duration, hundred seed weight, mucilage content, etc. Higher estimates of general combining ability (GCA) effects for pod yield per plant were observed in the parental lines UHFO-6 (123.47) and UHFO-9 (7.49). Among the cross combinations, UHFO-10 × Hisar Unnat (38.81), UHFO-2 × Pusa Bhindi-5 (38.29), UHFO-2 × Arka Anamika (17.42), and UHFO-5 × Arka Anamika (15.06) demonstrated higher estimates of specific combining ability (SCA) effects for pod yield per plant. The cross UHFO-2 × Hisar Unnat (160.00) exhibited the highest heterobeltiosis for mucilage content, while UHFO-10 × Arka Anamika (562.03) showed the highest standard heterosis for total polyphenol content. These cross combinations could produce okra with enhanced nutritional and medicinal properties. The highest GCA and SCA effects for pod yield per plant were observed in UHFO-6 (123.47) and UHFO-10 × Hisar Unnat (38.81), respectively. Identifying these parental lines and cross combinations based on their combining ability can result in the development of okra hybrids with substantially higher yields. In future, after multi-location trials, these parents and crosses can be released to replace existing okra cultivars (hybrids/varieties). Higher yielding and better quality okra cultivars can enhance the profitability for farmers, contribute to food security, and meet market demands more efficiently.

Keywords

• Combining ability
• Heterosis
• Hybrids
• Line × tester mating design
• Standard check