SSR Fingerprints Of Chinese Bayberry Cultivars And Multiple Fluorescent Markers For Identity Test

Chinese bayberry(Myrica rubra) is a subtropical evergreen fruit tree native to the southeast coastal and yunnan-guizhou plateau of China. It has a long history of cultivation with varoius local varieties and complex genetic diversity. As for the rapid development of Chinese bayberry industy, the genetic relationship and cultivar identification have been paid more and more attentions both by consumers and researchers. This research established the fingerprint of 123 commonly cultivated bayberry accessions based on fluorescent SSR markers, providing a basis for further cultival identification. The main results were summarized as follows:Establishment of Chinese bayberry fingerprint on SSR marker:A total of 14 fluorescent SSR primers were used to analyse the genetic diversity of the 122 Chinese bayberry accessions and one wax myrtle. The number of alleles (A) produced on each locus varied from 3 to 16; Polymorphism information content (PIC) ranged from 0.07 to 0.83 with an average of 0.62. observed heterozygosity(Ho) and expected heterozygosity(HE) ranged from 0.0080(MRU147) to 0.9200(MYB-SSR1) and 0.0701(MRU147) to 0.8525(MYB-SSR1) respectively. An unweighted pair-group method of the arithmetic averages(UPGMA) was also used to analyze the genetic relationships. When the Dice's similarity coefficient was 0.78, the 122 Chinese bayberries were divided into four groups. The first group further divided into 6 subgroups. Subgroupl contained 41 samples of which 36 accessions were from Zhejiang, Subgroup2 included a total of 32 accessions, Subgroup3 included 5 accessions, Subgroup4 include 3 accessions, Subgroup5 included 24 samples and Subgroup6 included 11 accessions both from Wenzhou. All the samples in this study could be distinguished by the 14 SSR markers, and the fingerprint layed foundation for identification of Chinese bayberry. Ten selected SSR markers were able to distinguish most accessions. There are two applications in actual production:for an unknown material, get the fingerprints on the 14 loci by fluorescent SSR markers and compared with the existing fingerprint profiles, achieve the goal on discrimination or identification of varities; for new varieties, genetic relationships can be deduced by cluster analysis with fingerprint profiles existed.Identify Chinese bayberry cultivars by multiplex PCR with fluorcent SSR markers:Ten SSR locis(MRU155, MRU386, MYB-SSR1, my0043, my0186, my0427, my0792, my0793, my0889 and my0972)were choosed, according to the factors of annealing temperature and the length of amplification, formed 4 multiplex PCR combination suitable for ABI3130 genetic sequences analyzer. Combination A includes my0186 and my0427; Combination B contains MRU386, MYB-SSR1 and my0043; Combination C includes my0889, my0972 and my0793; Combination D contains MRU155 and my0792. DNA used in the amplification were extracted from 8 Chinese bayberry fruits. By comparing with the established fingerprints above, we can identify 5 cultivars:'Shuijin','Fenhong', 'Yuelipan','Dingaomei'and'Wandaoyangmei';'Tanmei','Zaosuan'and the 'Y2010-75'showed a close relationship with'Yuhangdatanmei'and'Heitaner' 'Liuyemei'respectively. All these showed that this method is reliable, convienent and and high-throughput.