Abstract:

In this study， SCoT molecular markers were used to analyze the genetic diversity and construct DNA fingerprints of three species of Elymus on the Qinghai-Tibet Plateau to provide a theoretical basis for identification of the different species in collection material. Among 80 SCoT primers， 22 primers were selected for PCR amplification， and a total of 290 bands were amplified， of which 254 were polymorphic with the percentage of polymorphic bands （PPB） of 87.59%. The average values of the Shannon diversity information index （I）， Nei’s gene diversity index （H）， the observed number of alleles （Na）， and an effective number of alleles （Ne） were 0.5411， 0.3643， 1.9856， and 1.6270， respectively. Cluster analysis results showed that the genetic similarity coefficient ranged from 0.50 to 0.80. At a genetic similarity coefficient of 0.53， 46 collections could be divided into 2 groups， and the results of the principal coordinate analysis were consistent with those of cluster analysis. At the same time， the DNA fingerprints of 46 materials were constructed by using 4 SCoT primers. The SCoT molecular marker was suitable for genetic diversity analysis and DNA fingerprint construction of Elymus germplasm resources. This study provides fundamental information for germplasm identification， high-quality character mining， and breeding practice for wild Elymus.

Key words: Elymus, SCoT molecular marker, genetic diversity, fingerprint