Assessment of Genetic Variability and Divergence in Pointed Gourd Genotypes for Yield and Quality Parameters
Shiv Narayan Dhaker *
Department of Horticulture, Post-Graduate College of Agriculture, RPCAU, Pusa, Samastipur, Bihar, India.
Pramila
Department of Horticulture, Post-Graduate College of Agriculture, RPCAU, Pusa, Samastipur, Bihar, India.
Pandurang Nana Langute
Department of Horticulture, Post-Graduate College of Agriculture, RPCAU, Pusa, Samastipur, Bihar, India.
Udit Kumar
Department of Horticulture, Post-Graduate College of Agriculture, RPCAU, Pusa, Samastipur, Bihar, India.
Bishun Deo Prasad
Department of Agricultural Biotechnology and Molecular Biology, College of Basic Sciences and Humanities, RPCAU, Pusa, Samastipur, Bihar, India.
*Author to whom correspondence should be addressed.
Abstract
The present investigation was carried out during 2022–23 at the Vegetable Research Farm, Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur, Bihar, with the objective of assessing genetic variability, heritability, genetic advance, and genetic divergence among twenty pointed gourd (Trichosanthes dioica Roxb.) genotypes, including the check variety ‘Swarna Suruchi’. The experiment was conducted in a Randomized Block Design (RBD) with three replications, maintaining a spacing of 2 × 1 m. A total of fourteen yield and quality traits were recorded and subjected to statistical analysis. Analysis of variance revealed highly significant differences (p < 0.01) among genotypes for all traits, indicating considerable genetic variability. High genotypic (GCV) and phenotypic (PCV) coefficients of variation were observed for number of fruits plant⁻¹ (36.55%, 37.11%), number of vines plant⁻¹ (30.89%, 32.67%), fruiting duration (29.69%, 30.96%), seed:pulp ratio (22.38%, 23.95%) and fruit yield (22.12%, 25.56%), demonstrating substantial scope for improvement through selection. Seven traits number of vines plant⁻¹, vine length, internodal length, average fruit weight, number of seeds fruit⁻¹, fruit volume, and fruit yield exhibited high heritability (80.74–91.92%) coupled with high genetic advance (23.40–46.46%), suggesting the predominance of additive gene action and the effectiveness of selection in early generations. Among the evaluated genotypes, RPGS-3 and Kashi Alankar recorded significantly higher fruit yield and superior performance for most yield-contributing traits compared to the check. Mahalanobis D² analysis grouped the genotypes into six distinct clusters, with the maximum inter-cluster distance (D² = 876.82) observed between Cluster II and Cluster V, indicating the presence of wide genetic divergence. Traits contributing maximum towards genetic divergence included fruiting duration (34.60%), fruit length (30.72%), and seed:pulp ratio (16.20%). The overall results highlight promising genotypes and genetically diverse groups valuable for hybridization and future varietal improvement programs aimed at enhancing fruit yield and quality in pointed gourd.
Keywords: Pointed gourd, variability, heritability, GAM, genetic divergence