Studies on genetic divergence (D2) for fruit yield and its related traits in pumpkin (Cucurbita moschata Duch. ex. Poir)

Abstract

The experimental material consisted of 28 pumpkin genotypes including three standard checks viz., Arka Chandan, Azad Kaddu and Pusa Vikash was conducted in a Randomized Block Design with three replications. Analysis of variance studies indicated significant differences among all the genotypes for all the characters under study. Genetic diversity was worked out using Mahalanobis D 2 statistic. Based on D 2 analysis, the genotypes were grouped into 7 distinct non-overlapping clusters. Cluster I, II and III had 6 genotypes in each clusters. Cluster IV, V and VI also had 3 genotypes and cluster VII had presented only one genotype. The maximum intra-cluster distance was in cluster V (139.09) and minimum intracluster distance was found for cluster VII (0.00). Clustering pattern revealed that geographical diversity was not associated with genetic diversity of genotypes. The maximum inter-cluster distance was observed between clusters III to cluster VII (503.329), which suggested that members of these two clusters are genetically very diverse to each other. The inter cluster values between cluster I to cluster VII (398.733), V to VII (325.792), II to VII (315.975), V to VI (312.753) and I to V (309.983) were also high. The minimum inter-cluster D 2 value was recorded in case of cluster III to cluster IV (174.606). The wider genetic diversity were observed in cluster clusters I to VII, V to VII, II to VII, V to VI and I to V which indicated the potentiality of these diverse genotypes collection for providing basic material for future breeding programmes.

Genetic Estimations of Available Quality Traits for Improved Growth Yield of Pumpkin (Cucurbita moschata Duch) in Kumarganj, India

“…of nodes per plant (4.97) while the low estimate was observed for the fruit equatorial circumference (9.92), node number at first staminate flower anthesis (9.03), days to first staminate flower anthesis (7.68), days to first pistillate flower anthesis (3.78) and days to first fruit harvest (3.46)" [9]. Similar findings were also marked by earlier scientist in pumpkin [12][13][14][15].…”

“…"The estimates of coefficients of variation revealed that magnitude of phenotypic coefficients of variations (PCV) were higher than the genotypic coefficient, of variation (GCV) for all the characters indicating important role of environment. The phenotypic coefficient of variation ranged from 5.18 per cent (non reducing sugars) to 33.71 per cent (fruit yield per plant) for the various characters studied" [8] (Table 1).…”

Genetic Divergence and Character Association Studies in Pumpkin (Cucurbita moschata Duch ex. Poir)

“…A perusal of Table-3 showed that cluster means for different traits indicated considerable differences between the clusters". [7] All the clusters from cluster I to cluster VI had in general medium mean performance for most of the characters, exhibiting extreme cluster means for none of the character under the study.…”

“…The maximum inter-cluster distance was observed between clusters IV to cluster VI (1879.65), which suggested that members of these two clusters are genetically very diverse to each other. The inter cluster values between cluster I to IV (1100.17), V to VI (657.01), II to IV (1294.53), III to VI (1069.11) and IV to VI (1879.65) were very high" [7].…”

Evaluation of Genetic Divergence among Different Okra Genotypes

“…Analysis of contribution of the characters to genetic diversity revealed that characters like plant height (10.3%), branches per plant (0.4%), fruit weight (2.07%), yield per plant (3.4%) contributed to parameters of yield and different scientist also observed almost similar level of contribution for various growth and yield contributing characters [23,25,26,27,28,29,30,31].…”