Variability and inter-relationships of olive trees and cultivars using RAPD analysis

Random amplified polymorphic DNA sequence (RAPDs) analysis has been used to characterize two historic olivetums in Wagga Wagga and Yanco in southern New South Wales. We have checked the authenticity of some of the cultivars against international standards and have used the collection as a whole to determine the degree of genetic heterogeneity within and between cultivars. Using six selected oligonucleotide primers, we analysed DNA from 92 olive trees of the Wagga Wagga orchard (comprised of 46 named cultivars, 4 selections, and 4 trees of unknown or dubious origin), and from 35 trees of the Yanco orchard (comprised of 4 cultivars). The level of heterogeneity that was found suggests that many, if not all, cultivars are composed of varietal populations with often a considerable genetic overlap between cultivars.