Panghal, V.P.S.Sehgal, Nidhi2023-02-062023-02-062022-10https://krishikosh.egranth.ac.in/handle/1/5810193299The current investigation entitled “Genetic studies in bottle gourd [Lagenaria siceraria (Mol.) Standl.]” was conducted at Research Farm and laboratory of the Department of Vegetable Science, CCS Haryana Agricultural University, Hisar during kharif 2018, summer 2019 and kharif 2019. Bottle gourd accessions acquired from NBPGR, New Delhi were utilized for the genetical studies. In the current investigation, the magnitude of phenotypic coefficient of variation (PCV) was higher to that of genotypic coefficient of variation (GCV) for all the traits under examination suggesting that the apparent variation is attributed to environmental factors in addition to the genotypes. This further indicates improvement in fruit yield will be done by selection through these traits only on phenotypic basis. Fruit yield per vine had a positive and highly significant correlation with female-male flower ratio, number of fruits per vine, and average fruit weight at both genotypic and phenotypic levels. Heterosis studies revealed that the lines NDBG-10, IC-342077, IC-322278, IC-339209, IC-411915, Pusa Santushti, IC-342078 and IC-276413 are found to be more heterotic over better parent, local check (HBGH-35) as well as over national check (Pusa Hybrid-3). Therefore, these lines might be used as promising parents for hybridization programmes. Preponderance of dominant gene action along with over dominance in parents for most of the traits suggested that heterosis breeding approach might be more rewarding than selection in bottle gourd. The parent IC-342077, IC-342078 and Lucknow Collection were found to be the best general combiners for most of the traits based on the per se performance and gca effects and they may also act as valuable parents in hybridization or multiple crossing programme for obtaining high yielding varieties or transgressive segregants to produce new bottle gourd cultivars. Three crosses viz., IC-276413 × Pusa Santushti, IC-322278 × NDBG 10 and IC-398543 × Lucknow Collection are found to be the good specific combiners for fruit yield per vine as well as certain other yield attributes and therefore, might be utilized for yield enhancement in breeding programmes. Further, generation mean analysis via six parameter model revealed that the epistatic interaction model was sufficient to describe the type of gene action in majority of the parameters studied. In cross Pusa Naveen × G2, dominance (h) and dominance × dominance (l) gene effects displayed opposite signs for days to 50% germination, nodes to first female flower, days to anthesis of first staminate and pistillate flower, fruit diameter, length-diameter ratio of fruit and number of fruits per vine indicating duplicate epistasis which revealed that selection in later generations would be more effective for these traits.EnglishThesis