Genetic Variability, Correlation and Path Analysis in F3 and F4 Generation of Bottle Gourd [Lagenaria siceraria (Mol.) Standl.]

The bottle gourd is an important summer vegetable in India, but its productivity is hindered by biotic and abiotic stresses, challenging growing conditions and the lack of high-yielding varieties. Therefore, it is essential to understand its genetics to develop high-yielding cultivars. A thorough understanding of genotypic and phenotypic variability, heritability and genetic advance is necessary for a successful crop improvement program. Research conducted during the spring-summer and rainy seasons of 2021–22 at CCS HAU, Hisar, on the F3 and F4 generations of the bottle gourd cross GH-28 × Pusa Santushti, showed variability in various yield and yield-contributing traits. The fruit yield per hectare showed high values for genotypic coefficient of variation, phenotypic coefficient of variation, heritability and genetic advance in both generations, with progeny 4 performing best in yield-related traits fruit length (44.33cm and 41.17cm), average fruit weight (882.00g and 832.67g), number of fruits per vine (7.20 and 6.07) and fruit yield per plot (63.65Kg and 50.37Kg) was superior in both F3 to F4 generations, respectively. The observed changes in genetic variability across generations suggested heterozygosity, which may stabilize once homozygosity is achieved in later generations. Additionally, correlation analysis indicated that number of primary branches (0.778 and 0.904), average fruit weight (0.974 and 0.856), number of fruits per vine (0.995 and 0.682), days to first harvest (-0.624 and -0.784) and days to first female flower opening (-0.926 and -0.661) directly affected fruit yield per hectare in F3 and F4 generations, respectively. Similar traits were shown to influence fruit yield by path analysis studies Thus, selecting for these traits could significantly enhance a breeding program's success.