Abstract: Malus sieversii is a dominant species of relict broad-leaved wild fruit forests in the mountains of central Asia, which is usually distributed in piedmont belts at elevations from 1000 m to 1700 m. To investigate the response of population genetic characteristics of M. sieversii to elevational change, the Emin population, which has a large and continuous distribution covering a broad range of elevations, was sampled in this study. Microsatellites were used to identify the genotypes of 123 individuals from six sites with different elevations. The effects of elevation on the population genetic characteristics of the M. sieversiipopulation were investigated by analyzing the genetic diversity and phylogenetic relationships of individuals from different elevations. Genetic landscape analysis was conducted to determine the distribution pattern of alleles among the sampled individuals. The results showed that significant differences in genetic diversity existed among these elevations, with a unimodal distribution of genetic diversity. Significant genetic divergence was found among the low, middle and highelevation belts. These results indicated that changes in elevation profoundly influenced genetic diversity and genetic structure of M. sieversii population. Germplasm resources from different elevations should be considered in future germplasm resource protection.

Key words: Malus sieversii, elevation, genetic diversity, germplasm resource, Emin County.