Fast and reliable strawberry cultivar identification using inter simple sequence repeat (ISSR) amplification

ISSR amplification was evaluated for its applicability to strawberry varietalidentification. Eighteen primers based on various di- tri- or tetra- SSR motifswith 3 or 0 5'-selective nucleotides for anchoring were screened against thestrawberry genome by agarose gel electrophoresis. PCR conditions wereoptimised to obtain high quality patterns. Five primers that gave informativepatterns were selected and used to characterise, by polyacrylamide gelelectrophoresis, 30 strawberry varieties of various geographic and geneticorigins. A total of 390 bands, 113 of which were polymorphic (30%),were generated using these five primers. Genetic similarity between varietieswas estimated using Jaccard's coefficient of similarity. The associationsbetween varieties revealed by UPGMA analysis were consistent withpedigree data. With only one primer, all the varieties were distinguishedincluding those with a common pedigree. Banding patterns were highlyreproducible for DNA samples extracted from different tissues (leaves,sepals, and rhizomes) of the same plant, or from different plants (clones)of the same variety. ISSR technique is therefore a potentially useful tool forthe identification of strawberry varieties because it is simple, fast,cost-effective, highly discriminant and highly reliable.