Studies On Genetic Diversity And Genetic Structure Of Chinese Wild Cherry Prunus Pseudocerasus L.

Prunus pseudocerasus originated in China, belongs to Subgenus cerasus, Prunus,Rosaceae(Yu, 1986). P. pseudocerasus has more than 3000 years history, is mainly distributed in the Yangtze River Valley, has spread throughout the country to date, and is one of the most important and oldest cultivated fruit trees in China. P. pseudocerasus not only provides fruits, root stock, but also available for medicinal(Branches, leaves, roots and flowers). Due to the distribution of wild P. pseudocerasus, the diversity of germplasm resources is very rich, which provides the guarantee for the further development and utilization of wild P. pseudocerasus. In order to make better use of these abundant germplasm resources, we have done field investigation of the distribution of wild P. pseudocerasus and collected samples in 14 regions of 10 provinces(municipality) in China by studying the information from flora and herbarium. After the field investigation, 280 samples were collected. Genetic diversity and populations genetic structure of 14 wild P.pseudocerasus populations with 280 samples in China were investigated using SSR markers.The results are as follows:1. Through the investigation in 14 regions of 10 provinces(municipality) in China, we found that the wild P. pseudocerasus in China are suffering serious destruction with some reasons and sharply decreasing in some areas. It is necessary to take some measures to protect the wild resources in some areas.2. A total of 11 microsatellite primers selected from 100 primers which were chosen from P. avium, P. persica, P. salicina and P. pseudocerasus were used to amplify 280 P.pseudocerasus individuals. A total of 82 alleles of 11 loci were detected, the number of alleles per locus ranged from 4(UDP98-022) to 13(BPPCT005), and the average number of alleles per locus was 7.3. There were a greater number of SSR primer polymorphisms in Prunus avium than in Prunus persica(allele ratio of 8.5:6.0).3. The relatively high levels Shannon’s diversity( I : 0.9057–1.4684) and gene diversity(H:0.5431–0.7151)revealed relatively rich genetic diversity in Chinese wild P.pseudocerasus. Nei’s expected heterozygosity(h) is the most commonly used indicator to measure the genetic diversity of a population. According to the genetic diversity index, the genetic diversity levels of 14 Prunus pseudocerasus populations were obtained as follows:FHS > HPS > SNJ > TB > YJ > WB > BTM > JYS > NZ > YX > HLT > XZP > TS > LS.The highest genetic diversity was observed in the FHS population.4. The AMOVA analysis revealed pronounced genetic differentiation, with 70% of the total genetic variability partitioned within populations. Thus, the genetic differentiation within populations was higher than that among populations.5. The UPGMA tree clustered all of the populations into seven groups. The first group included BTM, WB, YJ, JYS, NZ, SNJ, and HPS; the second group included LS and TS; FHS,YX, HLT, XZP, and TB five populations were respectively classified into group three, group four, group five, group six, and group seven.