ABSTRACT
ObjectiveTo study the genetic diversity and genetic relationship of Pinellia ternata germplasm resources and provide the basis for germplasm identification， variety breeding， and resource conservation. MethodIn this study， 27 P. ternata were used as experimental materials to determine seven phenotypic characters， such as plant height， leaf length， and leaf width. Simple sequence repeats （SSR） primers were designed based on P. ternata transcriptome data， and polymerase chain reaction （PCR） amplification was performed on 27 P. ternata samples. The genetic diversity of P. ternata germplasm was analyzed by POPGENE32， PowerMarker V3.25， and NTSYS-PC 2.10e software. ResultA total of 10 pairs of highly polymorphic primers （PIC>0.5） and four pairs of moderately polymorphic primers （0.25<PIC<0.5） were selected. The average number of alleles detected was 3.928 6， and the average Nei's diversity index （H） and Shannon's index （I） were 0.557 8 and 1.002 9， respectively， indicating a high level of genetic diversity. Cluster analysis divided the Pinellia ternata into seven categories， and P. ternata in the same province were in the same categories. The SSR molecular ID cards of 27 P. ternata germplasm were constructed with 14 pairs of primers， and the rapid identification of P. ternata in each region was realized. ConclusionThe results of this study can lay a foundation for the genetic diversity and population structure of P. ternata and provide a scientific basis for the identification of P. ternata germplasm resources， map construction， and molecular-assisted breeding.
ABSTRACT
Polygonatum is a genus of the perennial herb family Liliaceae, with great potential in food, medicine and other field. In this study, genetic diversity and cluster structure analysis of 6 species in Polygonatum were investigated the molecular marker technique of simple sequence repeat (SSR). A total of 49 SSR makers were used to study genetic diversity and population structure within 60 germplasm resources which obtained from 38 counties and cities in 14 provinces of China. A total of 211 alleles were identified and the number of alleles ranged from 2 to 10, with an average of 4.306 1 alleles per SSR. The range of polymorphism information content (PIC) varied from 0.731 8 to 0.031 7, with the average of 0.309 6. The cluster analysis classified 60 germplasm resources into four defined groups at the genetic distance value of 0.26, among which most species with relatives were clustered into the same group. Extraordinarily, there were 6 germplasm resources clustered into other species, indicating that the classification of inter-genus and geographical distribution was crossed in Polygonatum. The genetic diversity index of the 4 geographical populations from high to low was: Western region, Central China, Southern China, Eastern China. The population structure analysis, also indicating divided the entire collection into four groups, which was similar to the assignment pattern of cluster structure analysis. These results suggested that the Polygonatum germplasm resources used in this study is rich in relatively high genetic diversity with large variation range, relatively fuzzy boundaries of species. It appeared the phenomenon that there is a difference decreases between the alternate leaf system and the rotation leaf system. The genetic diversity in the western region was higher than that in other regions, and the western region may be the origin center of the genus Polygonatum.