Classification of 75 strawberry cultivars and breeding lines using RAPD markers

Seventy-five strawberry genotypes were characterized using RAPD markers. Twenty primers were selected on the basis of a complete data set for all 75 accessions and the reproducibility of the amplification profile with the two DNA samples extracted from each genotype. A total of 91 informative loci were retained for phylogenetic analysis using maximum parsimony. Each primer provided an average of 4.6 informative loci using these selection criteria. The amplified DNA fragments ranged in size from approximately 0.3-2.0 kb. A consensus cladogram was constructed and represented the generic relationship between 75 strawberry genotypes. Three major clades were obtained and roughly corresponding to their geografical origins. This cladogram will be useful for breeding strawberries. For example, breeders use convergent crosses to improve agronomic traits of strawberry. In this case, the breeder wants to introduce the minimum genetic variation in a cross at the same time improve a trait. He will therefore chose lines that are close in the cladogram but differ for the trait. The cladogram and the table of pairwise genetic distances provide information on the relative genetic distance between all potential parents for a cross.