In order to study DNA polymorphism in barley, various STS primer-sets were tested on genomic DNAs of two Japanese barley cultivars. Out of total of 112 primer-sets used, 92 primer-sets generated DNA fragments either in one or both cultivars. Of 92 primer paris, 16 generated polymorphic fragments without using any restriction endonuclease. Twenty four monomorphic bands were converted to polymorphic bands after endonuclease digestion of PCR products with striction enzymes. The restriction sites occured less frequently and they were not evenly spaced out along the DNA fragments indicating that the nucleotides were not randomly ordered. The main reason for polymorphism observed in this study might be attributed to the absence or presence of restriction endonuclease sites.
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