protocol v1

SSR and SRAP markers were applied to assess the genetic diversity and structure of four populations of sixty-four samples ofEmmenopterys henryi. 12 pairs of SRAP primers generated 86 bands, and polymorphism rate was 88.4%. Higher values of genetic diversity parameters (h = 0.3195, I = 0.4757, PPB = 69377%, at the species level; h = 0.2632, I = 0.3868, PPB = 89.53%, at the population level) demonstrated relatively higher level of genetic diversity. A total of 150 alleles were detected using 10 pairs of SSR primer. The number of alleles per locus ranged from 7 to 24, with an average of 15 alleles of each locus. The genetic diversity parameters (h = 0.091, I = 0.176, PPB = 99.33%, at the species level; h = 0.0829, I = 0.1447, PPB = 50.34%, at the population level) were obtained. Population genetic differentiation level of E.henryi (SRAP, GST= 0.1936; SSR, GST = 0.0944) was higher compared to other species. AMOVA revealed that genetic variation mainly existed within populations. For SRAP markers, UPGMA dendrogram and PCA cluster analysis separate HS and DWS populations from other populations. But for SSR markers, UPGMA dendrogram and PCA cluster analysis divided 4 populations into 3 groups but was not obvious, and indicated the extent of admixture within some samples. It seemed the extant of genetic pattern of E.henryi might have mainly attributed to its long evolutionary history, wide-ranging distribution, outcross mating system and human activities. The genetic diversity parameters (Na, Ne, h, I)(except for Na at the species level ) revealed by SRAP markers were higher than that by SSR markers, but genetic distance calculated based on SSR markers was larger than that based on SRAP markers. Based on the conservation of germplasm resources and genetic diversity, the combination of SRAP and SSR markers could fully implement conservation and sustainable exploitation of the endangered plant E.henryi.