Characterization of the genetic relationships among biotypes of Malus prunifolia using simple sequence repeat marker

We used 10 simple sequence repeat primers in combination with touchdown PCR to evaluate the genetic relationships among 15 biotypes of Malus prunifolia. Out of 170 detected fragments, 156 (90.74%) were polymorphic. Coefficients of genetic similarity ranged from 0.53 to 0.88, with an average value of 0.66 between pairs of biotypes, which also indicated the high degree of polymorphism within this species. Cluster analysis sorted all biotypes into three groups, which was then confirmed by principal coordinate analysis. A dendrogram showed that some of the clustered biotypes were largely congruent for geographical distribution. However, the DNA patterns for some biotype groups did not demonstrate relative agreement in their origin. Five biotypes arising from the Xinjiang Autonomous Region were dispersed within the dendrogram, reflecting their complex genetic backgrounds.

► We analysis the genetic relationships among Malus prunifolia biotypes. ► SSR markers in combination with touchdown PCR were used in our research. ► Coefficients of genetic similarity ranged from 0.53 to 0.88. ► Cluster analysis sorted all biotypes into three groups. ► The results did not show relative agreement with some biotypes’ region of origin.