83 RAPD´s Analysis Support the Autochthon Origin of Olive Cultivars A. Belaj, I. Trujillo and L. Rallo Departamento de Agronomía Universidad de Córdoba Apartado 3048,14080, Córdoba. Spain Keywords: Olea europaea L., genetic distance, molecular markers. Abstract One-hundred-ninety RAPD fragments generated by the 46 selected primers were analysed for the study of genetic relatedness among Mediterranean and Iberian olive zones based on their geographic proximity. The study included 51 olive cultivars from nine Mediterranean countries (Algeria, Greece, Italy, Morocco, Portugal, Syria, Spain, Tunisia and Turkey). The data were elaborated using Chi- square distance defined by Benzecri (1970) and UPGMA clustering method. Factorial Correspondence Analyses were also applied for both Mediterranean and Iberian olive zones. The dendrograms obtained for these zones showed a tendency of clustering according to the geographic origin of the cultivars. Factorial Correspondence Analyses corroborated the above-mentioned results. These results agree with the hypothesis of the autochthon origin of olive and their limited diffusion out of their original zones. INTRODUCTION Good knowledge of genetic variability is an essential task in germplasm conservation and plant breeding program. Traditionally, the variability of Olea europaea L has been evaluated by morphological methods. However, a better knowledge of the relationships among cultivated olive, wild forms and related species could be possible by the use of biochemical and molecular analysis (Loukas and Krimbas, 1983; Trujillo et al., 1992; Ouazzani et al. 1993, Fabbri et al., 1995; Vergari et al., 1996; Angiolillo et al., 1999). The objective of this study is the evaluation of genetic relatedness among Mediterranean and Iberian olive zones based on their geographic proximity. MATERIAL AND METHODS RAPD data analysed in this paper were taken from the reported work of Belaj et al, 2000 (in press). These authors studied the discrimination capacity of RAPD markers in a Germplasm Bank. Table 1 indicates the cultivars studied, their countries of origin and their register number in the Olive Germplasm Bank “Alameda del Obispo” of Córdoba (Spain). Three Mediterranean zones were established considering the countries of origin of the cultivars: 1. East Mediterranean (Syria, Turkey and Greece), 2. Central Mediterranean (Italy, Tunisia and Algeria) and 3. West Mediterranean zone (Morocco, Spain and Portugal). All Spanish and a few Portuguese cultivars were included in the study of Iberian olive zones according to their geographic proximity (Fig. 1). These zones were: 1. The zone of Levante (East of Spain), 2. The Central zone (also including the Portuguese cultivars 'Cobrançosa' and 'Galega'), 3. The zone of Andalusia (South of Spain) including the Portuguese cultivar 'Cordovil de Serpa'. Dendrograms of both Mediterranean and Iberian zones were based on the chi-square distance of Benzecri (1970) applying UPGMA clustering method. To evaluate how well the dendrograms and the original distance matrices match, cophenetic correlation coefficients were calculated. Factorial Correspondence Analyses (Benzecri and Benzecri, 1980) were also applied in the study of these zones. The computer program used in the study was NTSYS (Numerical Taxonomy System) version 1.50 (1980). RESULTS AND DISCUSSION Mediterranean zones clustered according to their geographic proximity (Fig.2a). Proc. 4 th IS on Olive Growing Eds. C. Vitagliano & G.P. Martelli Acta Hort. 586, ISHS 2002