Heterotic potential and combining ability for yield and quality attributes in slicing cucumber (Cucumis sativus L.)

The present investigation was conducted to evaluate the heterotic potential and combining ability of cucumber genotypes for the development of early maturing, high yielding and better quality hybrids suitable for tropical environment. The experimental material consisted of eight monoecious parental lines, which were intercrossed using a half-diallel mating design (excluding reciprocals), resulting in 28 F₁ hybrids. A commercial hybrid, 'Nazia', was included as a standard check. These 36 genotypes (parents and hybrids) were evaluated under tropical conditions for yield and quality-related traits. Analysis of variance revealed highly significant differences (p ≤ 0.01) among genotypes for all the studied traits, indicating the presence of substantial genetic variability. The significant mean squares due to general and specific combining ability (GCA) and specific combining ability (SCA) suggest the involvement of both additive and non-additive gene actions in the inheritance of the traits evaluated. Among the parents, line D-20 emerged as the best general combiner for key traits, including node number for the first female flower appearance, fruit yield per plant, fruit number per plant and sex ratio. Punjab Naveen showed superior GCA for fruit diameter and ascorbic acid content. Based on heterosis, mean performance, and SCA effects, hybrids D-20 × Pant Kheera-1, D-20 × JLG and D-20 × Punjab Naveen demonstrated superior performance for yield and quality traits. Additionally, D-20 × Punjab Naveen and D-20 × Pusa Uday produced female flowers at lower nodes, a desirable trait for early yield. Notably, the combinations Punjab Naveen × Pant Kheera-1 and CMVR-1 × JLG were the earliest to mature. Considering overall performance and combining ability, hybrids D-20 × Pant Kheera-1 and D-20 × Punjab Naveen are promising candidates for commercial cultivation in the summer season, subject to validation through multi-location trials. Furthermore, the genetic analysis indicated that most traits, except fruit diameter and ascorbic acid content were predominantly controlled by non-additive gene action, highlighting the potential of these traits in hybrid development programs.