Study of Genetic Diversity in Pumpkin (Cucurbita Moschata L.)

Abstract

Twenty-five diverse genotypes were evaluated at Horticulture Research Centre of SVP University of Agriculture & Technology, Meerut during summer season, 2020. The experiment was laid out in Randomized block design with three replications. The analysis of variance revealed significant among all the genotypes for all the characters under study. The high percentage of genotypic coefficient of variation and phenotypic coefficient of variation for number of fruits per plant, number of primary branches, while, moderate were found for fruit yield per plant, % of seed germination, numbers of leaf per plant, days to first fruit harvest, length of vine, days to first fruit set and days to first flower initiation and lowest in days to 50% flowering, which estimated that high degree of variability in these characters and suggested that possibility of yield improvement through selection of this traits. The estimates heritability ranged from 97.40% for number of fruits per plant to 66.29 % for days to 50% flowering. The highest heritability recorded for days to first fruit harvest, days to first fruit set, number of leaf per plant, number of primary branches, fruit yield per plant, % of seed germination. Genetic advance as % of mean was highest for number of fruits per plant, number of primary branches, fruit yield per plant, % of seed germination, numbers of leaf per plant, days to first fruit harvest. Which indicates that above characters may be most potential for further improvement. The genotypic correlation was higher in magnitude than the phenotypic correlation coefficient. Fruit yield per plant was highly significant and positive correlation with number of fruits per plant, numbers of leaf per plant, length of vine, number of primary branches, days to first fruit harvest and days to first fruit set. Path analysis result was recorded positive and direct effect on fruit yield per plant were exerted by number of primary branches, number of fruits per plant, days to first fruit set, numbers of leaf per plant, length of vine, days to first flower initiation and % of seed germination. Fruit yield per plant was exerted by days to 50 % flowering and days to first fruit harvest was recorded negative direct effect. Mahalanobis D2 statistics revealed that a considerable genetic diversity was found among genotypes. Twenty-five genotypes of pumpkin were formed five clusters. The cluster II comprised highest 9 genotypes, cluster V comprised 9 genotypes, Cluster I comprised 4 genotypes, Cluster IV comprised 2 genotypes and minimum in cluster III comprised 1 genotype. The maximum intra-cluster distance was recorded in cluster II, cluster I, cluster V, IV and cluster III with minimum intra-cluster distance, suggesting that the genotypes of cluster II are more heterogeneous whereas, genotypes of cluster II are homogeneous based on intra-cluster distance. The maximum inter-cluster distance was recorded in cluster III and Cluster I. Whereas, the minimum inter- cluster distance was observed in cluster V and cluster I