Morphological and isozyme characterization of local grapevine (vitis vinifera L.)cultivars of Ethiopia

Sixteen Ethiopian local grapevine cultivars (Vitis vinifera L.)were characterized using nineteen morphological (9 quantitative and 10 qualitative)traits and six isozyme systems. Morphological characterization was conducted in randomized complete bock design with three replications during 2003/2004 cropping season. The analysis of variance of the quantitative traits showed significant (p0.01)variation among the cultivars for all traits but number of lobes. Estimates of variability parameters such as phenotypic coefficient of variation (PCV)and genotypic coefficient of variation (GCV), heritability, genotypic and phenotypic variances showed the presence of some variability. Relatively higher PCV and GCV were observed for yield, 100-seed weight and tendril length. Bunch length and size of blade showed relatively lower GCV. Higher heritability values were obtained for berry size, size of leaf blade and tendril length. Correlation analysis showed that bunch length and tendril length were positively and significantly correlated at both genotypic and phenotypic levels whereas negative significant genotypic and phenotypic association was observed between berry size and bunch length. Yield was found to be positively associated with 100-seed weight, berry size, bunch length. Yield was found to be positively associated with 100-seed weight, berry size, bunch length at genotypic and phenotypic levels. Analysis of variance, estimated contribution towards divergence, and analysis of PCV and GCV showed that 100-seed weight, bunch density and color of upper surface of leaf have high discriminating power on the characterization of the Ethiopian local grapevine cultivars. Hierarchial average linkage cluster analysis using Mahalanobis squared D statistics grouped the cultivars into six and four clusters based on qualitative and quantitative traits, respectively. The squared X test revealed that all intra-cluster squared distances were non-significant and all inter-cluster squared distances were highly significant (p0.01)for both traits indicating that there is no significant variation among cultivars within same clusters. In the present work, five cultivars (Aterie 3, Nech Dubie, Amedam, Aterie 1 and Sebat Tewdage)were observed to be grouped into the same clusters for both qualitative and quantitative traits analyzed. Also, two cultivars (Nech Shul and Elabred White)were grouped in one cluster, as well. The close similarities among these cultivars were further justified by non-significant squared X test of the intra-cluster squared distances of the clusters to which these cultivar belong. From the six enzyme systems tested alpha-EST and B-EST and AAT showed monomorphic double bands for all sample and the rest (IDH, PER, PGI, and ME)showed single bands in all samples. The morphological data showed the variation within Ethiopian local grapevine cultivars was more of phenotypical as no variation was observed at isozyme level. The present study suggests, more sensitive molecular techniques should be adopted to further investigate the variation among the Ethiopian local grapevine cultivars in the future.