Estimation of phenotypic divergence in a collection of muskmelon germplasm, including Indian and exotic populations

Abstract

Seventy melon genotypes, comprising of landraces, inbred lines and cultivars collected from diverse geographical locations, were evaluated for 17 morphological traits for determining the patterns of genetic diversity and relationship among genotypes. The genetic diversity based on quantitative and qualitative characters of genotypes was assessed by D2 analysis. The Euclidean’s distance-based clustering divided the germplasm in to nine clusters. Though the analysis of 17 descriptors distinctly separated momordica and wild accessions from cantalupensis, reticulatus, inodorus accessions, but it was not able to differentiate cantalupensis, reticulatus, inodorus group accessions. The inter-cluster distance varied from 759.6 between clusters 1 and 2 to 5194.5 between clusters 4 and 8. The maximum intra-cluster distance matrix was observed in cluster 9 (728.5), while cluster 6 exhibited the minimum intracluster variation (344.0). Maximum number of genotypes was grouped in cluster 1 and 7 i.e. 15 in each group. The genotype “Canary Yellow-2” present in cluster 4 did not grouped in any cluster. Overall, the clustering patterns exhibited great diversity in the germplasm for certain traits (fruit morphology and quality characteristics) which can be effectively utilized for broadening the genetic base of muskmelon germplasm and for developing specialty melon cultivars/ hybrids with unique traits such as high beta carotene, sweetness and extended shelf life.