Complete chloroplast genome of Ligustrum lucidum and highly variable marker identification for Ligustrum / 中国中药杂志

Ligustri Lucidi Fructus, the sun-dried mature fruit of Ligustrum lucidum, is cool, plain, sweet, and bitter, which can be used as both food and medicine, with the effects of improving vision, blacking hair, and tonifying liver and kidney. It takes effect slowly. However, little is known about the genetic information of the medicinal plant and it is still a challenge to distinguish Ligustrum species. In this study, the complete chloroplast genome of L. lucidum was obtained by genome skimming and then compared with that of five other Ligustrum species, which had been reported. This study aims to evaluate the interspecific variation of chloroplast genome within the genus and develop molecular markers for species identification of the genus. The result showed that the chloroplast genome of L. lucidum was 162 162 bp with a circular quadripartite structure of two single-copy regions separated by a pair of inverted repeats. The Ligustrum chloroplast genomes were conserved with small interspecific difference. Comparative analysis of six Ligustrum chloroplast genomes revealed three variable regions(rbcL-accD, ycf1a, and ycf1b), and ycf1a and ycf1b can be used as the species-specific DNA barcode for Ligustrum. Phylogeny analysis provided the best resolution of Ligustrum and supported that L. lucidum was sister to L. gracile. This study clarified the genetic diversity of L. lucidum from provenance, which can serve as a reference for further analysis of pharmacological differences and breeding of excellent varieties with stable drug effects.

Evaluation of genetic diversity of ginseng fruit color germplasm resources: based on SSR analysis / 中国中药杂志

Illumina Xten was employed for shallow sequencing of Panax ginseng(ginseng) samples, MISA for screening of SSR loci, and Primer 3 for primer design. Polymorphic primers were screened from 180 primers. From the successfully amplified polymorphic primers, 15 primers which featured clear peak shape, good polymorphism, and ease of statistics were selected and used to evaluate the genetic diversity and germplasm resources of 36 ginseng accessions with different fruit colors from Jilin province. The results showed that red-fruit ginseng population had high genetic diversity with the average number of alleles(N_a) of 1.031 and haploid genetic diversity(h) of 0.172. The neighbor-joining cluster analysis demonstrated that the germplasms of red-fruit and yellow-fruit ginseng populations were obviously intermixed, and pick-fruit ginseng germplasms clustered into a single clade. The results of STRUCTURE analysis showed high proportion of single genotype in pick-fruit ginseng germplasm and abundant genotypes in red-fruit and yellow-fruit ginseng germplasms with obvious germplasm mixing. AMOVA revealed that genetic variation occurred mainly within populations(62.00%, P<0.001), and rarely among populations(39%, P<0.001), but homogenization was obvious among different populations. In summary, pink-fruit ginseng population may contain rare genotypes, which is the basis for breeding of high-quality high-yield, and multi-resistance varieties, genetic improvement of varieties, and sustainable development and utilization of ginseng germplasm resources.