Abstract

Abstract: Fourteen quantitative characters were measured in 20 accessions of 'egusi' melon. Principal Component Analysis (PCA) and Single Linkage Cluster Analysis (SLCA) were employed to analyse the variation pattern in these accessions. The first three principal components accounted for 76.33% and 78.70% of the total variation in the early and late seasons respectively. SLCA summarized the relationship among the accessions at various levels of similarity into a dendogram while the accessions were sorted into six distinct groups. The implication of these results for 'egusi' melon breeding is discussed. INTRODUCTION In cross pollinated crops such as 'egusi' melon, germplasm often exist in the form of heterozygous genotypes which could be improved through intraspecific hybridization and selection. Development of improved varieties of crop plant necessarily involves the incorporation of specific gene complexes governing desired traits. Plant breeders firstly identify traits in plant species that makes them suitable for utilization by man, then search out new genes for the desired traits in new cultivars (or strains) using traditional techniques or biotechnology. They then finally access the performance of the new cultivars before releasing them as registered cultivars to be grown widely by farmers and enjoyed by consumers. It is important to classify the range of variability among accessions to facilitate the maintenance and further acquisition of germplasm resources. Thus, the wealth of any germplasm collection is measured in terms of the genetic variability of the crop species it contains. Many techniques have been employed by researchers to determine the extent of variability in a germplasm collection. The Principal component analysis (PCA) has been used to measure genetic divergence among genotypes. This method which is a common ordination technique reduces the dimension of multivariate data by removing inter-correlations among attribute-variables (characters on which units are to be compared), and enables multidimensional relationships to be plotted on two or three principal axes