Assessment of Genetic Variability and Identification of Superior Recombinants in a Double-Cross-Derived F₂ Population of Okra (Abelmoschus esculentus (L.) Moench) for Inbred Line Development

Abstract

Genetic recombination among diverse elite parental lines is an effective strategy for broadening the genetic base and developing superior inbred lines in okra (Abelmoschus esculentus (L.) Moench). Among 45 double-cross hybrids developed by crossing ten commercial single-cross hybrids in a half-diallel mating design, BDCH-23 [SCH-3 (Sun-28) × SCH-9 (Abhay)] was identified as the superior cross combination and advanced to the F₂ generation. The resulting population of 182 F₂ plants was evaluated under unreplicated field conditions during summer 2025 at the University of Agricultural Sciences, Dharwad, India, to assess genetic variability and identify superior recombinants for fruit yield and its component traits. Each plant was considered a genetically distinct segregating genotype. The population exhibited wide phenotypic variation, indicating recombination of favourable alleles from diverse parental backgrounds. Fruit yield per plant recorded high phenotypic and genotypic coefficients of variation (38.79% and 36.59%, respectively), high heritability (88.95%) and high genetic advance as per cent of mean (71.08%), suggesting the predominance of additive gene action and the usefulness of selection in the segregating generation. Number of fruits per plant and average fruit weight also showed favourable genetic parameters, indicating their relevance as supporting selection criteria for yield improvement. Superior recombinants were identified as plants whose mean performance exceeded the population mean by one standard deviation. On this basis, 14.28% of the F₂ plants were classified as superior transgressive segregants for fruit yield per plant. Genotype P-430 recorded the highest fruit yield (999.80 g plant⁻¹), representing a 69.77% increase over the standard check. These results indicate that the BDCH-23-derived F₂ population provides useful variability for selecting promising recombinants for inbred line development in okra.