Comprehensive quantitative genetic evaluation of phenotypic variability, heritability coefficients and expected genetic gain for yield and its associated traits in bitter gourd (Momordica charantia L.) under diverse agro-ecological conditions of the

The study was conducted over two years to investigate genetic variability, heritability and genetic advance as a percentage of the mean among 40 genotypes of bitter gourd (Momordia charantia L.). The genotypes were cultivated at the Horticulture Research Centre, SVPUAT, Modipuram (Meerut), during the Zaid seasons of 2023 and 2024. The experiment followed a randomized block design (RBD) with three replications and a spacing of 1 m × 0.75 m. A total of sixteen quantative traits were recorded and analyzed to identify genetic factors contributing to enhanced yield potential. Analysis of variance (ANOVA) revealed that mean squares due to genotypes were significant for all the traits studied. The pooled phenotypic coefficient of variation (PCV) exhibited an average increase of about 5 % over the genotypic coefficient of variation (GCV), with mean values of 11.06 % and 10.07 %, respectively. In 2023, the highest genotypic and phenotypic coefficients of variation were observed for primary branches per vine (23.24 and 23.57, respectively), whereas in 2024, the maximum values were recorded for total fruit yield per vine (41.93 and 42.22 respectively). Similarly, heritability (broad sense, h2bs) and genetic advance (GA) were highest for primary branches per vine in 2023 (97.28 % and 47.22 %, respectively, while in 2024, total fruit yield per vine recorded the maximum heritability and genetic advance (98.67 % and 85.82 %, respectively). Overall, traits exhibiting high PCV and GCV values corresponded with high heritability and genetic advance estimates for the same characters, indicating the predominance of additive gene action and the potential for improvement through simple selection.