Exploitation of Heterosis and Combining Ability for Total Soluble Solids, Ascorbic Acid and Flesh Thickness in Sponge Gourd (Luffa cylindrica (L) Roem.)

Abstract

The present investigation was carried out to assess heterosis, combining ability and gene action for important fruit quality traits in sponge gourd (Luffa cylindrica (L) Roem.). Nine parents were crossed in a half-diallel mating design to generate 36 F₁ hybrids along with two commercial checks (Kashi Saumya and NSGH-341) and were evaluated during the Kharif seasons of 2024 and 2025 using RBD with three replications. Based on pooled analysis across seasons, Kashi Shreya × Kashi Vandana recorded the highest mid-parent heterosis (56.73%) and better-parent heterosis (48.53%) for total soluble solids. In comparison, Pusa Sneha × Kashi Vandana expressed the maximum standard heterosis over Kashi Saumya (83.44%) and NSGH-341 (47.63%), for ascorbic acid content VRSG-2/13 × VRSG-8 showed the highest mid-parent (29.12%) and better-parent heterosis (26.01%). In contrast, Pusa Sneha × Kashi Vandana registered the highest standard heterosis over Kashi Saumya (44.88%) and NSGH-341 (21.17%). For flesh thickness, the highest mid-parent (30.33%) and better-parent heterosis (23.76%) were recorded in Kashi Shreya × Kashi Jyoti, while Pusa Chikni × Kashi Shreya recorded the maximum standard heterosis over Kashi Saumya (32.62%) and NSGH-341 (19.67%). Combining ability analysis revealed Pusa Sneha (0.35) has the best general combining ability (GCA) for total soluble solids, Kashi Shreya (0.30) for ascorbic acid content and Kashi Kalyani (0.26) for flesh thickness. The hybrids Pusa Sneha × Kashi Vandana (0.91), VRSG-2/13 × VRSG-8 (0.66) and Kashi Shreya × Kashi Jyoti (0.50) exhibited the highest specific combining ability (GCA) for total soluble solids, ascorbic acid content and flesh thickness, respectively. The predominance of SCA variance over GCA variance for all quality traits indicated the major role of non-additive gene action. The identified hybrids and parental lines offer considerable potential for developing high-quality sponge gourd hybrids through heterosis breeding.