Unlocking the genetic potential of bottle gourd (Lagenaria siceraria (Molina) Standl.): analyzing yield and agronomic traits through combining ability and heterosis

This study evaluated the combining ability and heterosis of fourteen genotypes using a Line × Tester mating design, aimed at identifying superior parental lines for enhancing agronomic traits in the Kharif 2023 season. The genotypes, comprising 10 lines and 4 testers, were crossed to generate 40 F1 hybrids, which were assessed alongside 14 parental genotypes and a commercial check in experimental field trials at Lovely Professional University during late summer 2024. The experiment was conducted using an alpha lattice design with two replications, focusing on 12 traits including days to flowering, fruit characteristics and yield. Analysis of variance (ANOVA) revealed highly significant differences for all traits, indicating substantial genetic variability among the genotypes. General combining ability (GCA) and specific combining ability (SCA) estimates were used to assess the genetic potential of the genotypes, with notable effects observed for traits like early flowering (GCA and SCA effects for DMF ranging from -3.48** to 2.53 and -10.60** to 5.88, DFF ranging from -4.05** to 3.70 and -10.60** to 4.93), vine length (GCA and SCA effects for VL ranging from -84.78 to 79.20** and -125.17 to 240.32**) and fruit yield (GCA and SCA effects for FYPP ranging from -1.28 to 0.97 and -4.32 to 6.97**). Heterosis analysis demonstrated significant positive heterosis for fruit yield per plant, with crosses such as N/06-40 × Punjab Round exhibiting impressive hybrid vigor. The study also identified distinct heterotic groups through dendrogram analysis, providing insights into the genetic dissimilarity among the genotypes. Overall, the findings underscore the importance of both additive and non-additive genetic effects in trait improvement and offer valuable guidance for future breeding strategies to optimize crop performance and yield.