Phylogenetic relationships among genotypes of worldwide collection of spring and winter ryes (Secale cereale L.) determined by RAPD-PCR markers.

Genetic similarities among 20 spring and 22 winter accessions of agronomically different ryes from fourteen countries were estimated by employing random amplified polymorphic DNA (RAPD) techniques. Cluster analysis of genetic distance data showed that 42 genotypes were readily classifiable into two main groups: spring and winter groups. Within the spring group, cultivars fell into a North European and an American-Chinese group. Cultivars of winter rye fell into four groups: Northern European, Russian, American and Chinese lines. A UPGMA-dendrogram based on genetic distances of cultivars of rye within the winter and spring groups showed that the clusters corresponded well to their geographical locations. The results indicated that isolation has played an important role in the evolution of rye, and that temporal isolation has influenced the genetic diversity of rye more than geographical isolation. In this experiment, RAPD proved to be a rapid, reliable and practicable method of revealing polymorphisms in rye populations.