Abstract:

Currently，systematic genetic evaluation of Xinjiang peach landrace germplasm remains limited. A total of 153 Xinjiang peach landrace accessions were selected and analyzed using 16 SSR primers for multi-dimensional analyses（genetic diversity，cluster analysis，and population structure analysis）to systematically unravel their genetic variation patterns. Meanwhile，a DNA fingerprint database for Xinjiang peach landrace varieties was successfully constructed based on capillary electrophoresis. The main results are as follows：(1) The 16 SSR primer pairs amplified 121 polymorphic loci across the 153 peach accessions；the effective number of alleles（N_e）ranged from 1.10 to 4.70，Shannon’s information index（I）from 0.23 to 1.78，observed heterozygosity（H_o）from 0.05 to 0.26，expected heterozygosity （H_e）from 0.09 to 0.79，and polymorphism information content（PIC）from 0.09 to 0.76（mean 0.50）. (2) UPGMA cluster analysis divided the 153 accessions into 9 groups with an average genetic distance of 0.50；the clustering showed no significant correlation with geographical origin or peach type. (3) STRUCTURE-based population genetic structure analysis indicated that the 153 accessions could be partitioned into three subpopulations，which were speculated to correspond to wild types，landraces，and cultivated cultivars. (4) Using a core set of SSR primers covering the eight chromosomes of the peach genome，molecular identification codes were successfully established for 128 Xinjiang peach landrace accessions，providing a molecular basis for the standardized construction of core germplasm collections and the mining of elite genes.

Key words: Prunus persica, Prunus ferganensis, germplasm, SSR markers, genetic diversity, DNA fingerprinting