The Development Of Ssr Markers From Polygonatum Cyrtonema, And Their Application

Polygonatum cyrtonema, a perennial herb endemic to China, is one of about 60 species in the genus Polygonatum and mainly distributed in the Yangtze River Basin. Their rhizomes have been used in traditional Chinese medicine for a long time. Recently, it has been reported that the volatile oil of P. cyrtonema may inhibit the growth of the bacteria Escherichia coli and Staphylococcus aureus and the fungus Rhodotorula glutinis, and also inhibit the growth of cultured human non-small cell lung cancer cells. Moreover, P. cyrtonema has great interest in horticulture due to its small, greenish-white, pendulous flowers with large and alternate leaves. However, today the wild populations of P. cyrtonema have been reduced dramatically because of human activities. Understanding genetic variation within and among natural populations can tell us the fundamental information of evolutionary processes and can help present effective conservation strategies.Simple-sequence repeats (SSRs) or microsatellites are tandem repeats of 1-6 bp nucleotides. SSRs have been developed into one of the most popular genetic markers due to their high reproducibility, multi-allelic nature, co-dominant inheritance, high abundance and wide genome coverage. Microsatellites have been used for studies of genomic mapping, phylogenetics, population genetics and conservation biology.Here, we report the isolation and characterization of twelve polymorphic microsatellite loci from P. cyrtonema using a biotin-capture method. In total, 110 positive clones were sequenced. Fifty-five pairs of primers were designed and synthesized. Twenty-two sets of primers that gave consistent and specific PCR products were tested for allelic polymorphism from 23 individuals of a natural population in the south of Anhui Province. Out of the Twenty-two primers, twelve were polymorphic. The number of alleles ranged from 2 to 11, and the observed and expected heterozygosities ranged from 0.273 to 0.727 and from 0.268 to 0.865, respectively. These microsatellite loci were cross-amplified for four congeneric species and nine loci can be amplified successfully in all four species. The results suggest that these microsatellite markers would contribute to the population genetic studies and germplasm preservation of P. cyrtonema and other related species.