[Comparative analysis of plastomes of Rubus chingii and R. chingii var. suavissimus].

Rubus chingii and R. chingii var. suavissimus are unique dual-purpose plant resources, with significant nutraceutical, pharmaceutical, and economic value, as well as promising prospects for further development. To investigate the genetic structure and evolutionary characteristics of these two varieties, this study conducted plastome sequencing using the Illumina HiSeq XTen sequencing platform. Subsequently, the study performed assembly, annotation, and characterization of the genomes, followed by a comparative plastome and phylogenetic analysis using bioinformatics techniques. The results revealed that the plastomes of R. chingii and R. chingii var. suavissimus exhibited a tetrad structure, comprising a large single-copy region(LSC), a small single-copy region(SSC), and two inverted repeat regions(IRs). The study identified a total of 56 simple sequence repeats(SSRs) after comparative analysis, predominantly consisting of A and T. Furthermore, the structure of the IR boundary genes in both varieties was found to be highly conserved, with only minor nucleotide variations. Additionally, the study identified three highly variable regions: rps16-trnQ-psbK, trnR-atpA, and trnT-trnL, which held promise as potential identification marks for further development and utilization. Phylogenetic analysis results obtained by the maximum likelihood and Bayesian inference methods demonstrated a close clustering of R. chingii and R. chingii var. suavissimus(100% support), with their closest relatives being R. trianthus. This study, focusing on plastome-level genetic distinctions between these two varieties, lays a foundation for future species protection, development, and utilization.

Genetic diversities in wild and cultivated populations of the two closely-related medical plants species, Tripterygium Wilfordii and T. Hypoglaucum (Celastraceae).

BACKGROUND: The sustainable supply of medicinal plants is important, and cultivating and domesticating them has been suggested as an optimal strategy. However, this can lead to a loss of genetic diversity. Tripterygium wilfordii Hook. f. is a medicinal plant commonly used in traditional Chinese medicine, but its wild populations are dwindling due to excessive harvesting. To protect the species and meet the increasing demand, it is urgent to cultivate it on a large scale. However, distinguishing between T. wilfordii and T. hypoglaucum, two similar species with different medicinal properties, is challenging. Therefore, it is crucial to understand the genetic diversity and population structure of these species for their sustainable utilization. RESULTS: In this study, we investigated the genetic diversity and population structure of the two traditional medicinal semiwoody vines plant species, Tripterygium wilfordii and T. hypoglaucum, including wild and cultivated populations using chloroplast DNA (cpDNA) sequences and microsatellite loci. Our results indicated that the two species maintain a high level of genetic divergence, indicating possible genetic bases for the different contents of bioactive compounds of the two species. T. wilfordii showed lower genetic diversity and less subdivided population structures of both markers than T. hypoglaucum. The potential factors in shaping these interesting differences might be differentiated pollen-to-seed migration rates, interbreeding, and history of population divergence. Analyses of cpDNA and microsatellite loci supported that the two species are genetically distinct entities. In addition, a significant reduction of genetic diversity was observed for cultivated populations of the two species, which mainly resulted from the small initial population size and propagated vegetative practice during their cultivation. CONCLUSION: Our findings indicate significant genetic divergence between T. wilfordii and T. hypoglaucum. The genetic diversity and population structure analyses provide important insights into the sustainable cultivation and utilization of these medicinal plants. Accurate identification and conservation efforts are necessary for both species to ensure the safety and effectiveness of crude drug use. Our study also highlighted the importance of combined analyses of different DNA markers in addressing population genetics of medicinal plants because of the contrasts of inheritance and rates of gene flow. Large-scale cultivation programs should consider preserving genetic diversity to enhance the long-term sustainability of T. wilfordii and T. hypoglaucum. Our study proposed that some populations showed higher genetic diversity and distinctness, which can be considered with priority for conservation and as the sources for future breeding and genetic improvement.

Genetic diversity and population divergence of Leonurus japonicus and its distribution dynamic changes from the last interglacial to the present in China.

BACKGROUND: Leonurus japonicus, a significant medicinal plant known for its therapeutic effects on gynecological and cardiovascular diseases, has genetic diversity that forms the basis for germplasm preservation and utilization in medicine. Despite its economic value, limited research has focused on its genetic diversity and divergence. RESULTS: The avg. nucleotide diversity of 59 accessions from China were 0.00029 and hotspot regions in petN-psbM and rpl32-trnL(UAG) spacers, which can be used for genotype discrimination. These accessions divided into four clades with significant divergence. The four subclades, which split at approximately 7.36 Ma, were likely influenced by the Hengduan Mountains uplift and global temperature drop. The initial divergence gave rise to Clade D, with a crown age estimated at 4.27 Ma, followed by Clade C, with a crown age estimated at 3.39 Ma. The four clades were not showed a clear spatial distribution. Suitable climatic conditions for the species were identified, including warmest quarter precipitation 433.20 mm ~ 1,524.07 mm, driest month precipitation > 12.06 mm, and coldest month min temp > -4.34 °C. The high suitability distribution showed contraction in LIG to LGM, followed by expansion from LGM to present. The Hengduan Mountains acted as a glacial refuge for the species during climate changes. CONCLUSIONS: Our findings reflected a clear phylogenetic relationships and divergence within species L. japonicus and the identified hotspot regions could facilitate the genotype discrimination. The divergence time estimation and suitable area simulation revealed evolution dynamics of this species and may propose conservation suggestions and exploitation approaches in the future.

[Current status and development strategy of ISO/TC 249 standards for Chinese materia medica].

The internationalization of traditional Chinese medicine(TCM) is one of the strategic development objectives in China, which has been incorporated into the national strategy as an important part of the Belt and Road Initiative development strategy. As the basis and prerequisite of TCM development, Chinese materia medica(CMM) has a direct impact on the internationalization of TCM. The International Organization for Standardization(ISO) is a global organization composed of national standardization bodies, and the ISO standards impact the world's economy, trade, communication and cooperation. Based on a brief introduction to ISO/Traditional Chinese Medicine Technical Committee(ISO/TC 249), this study elaborates the necessity of establishing ISO standards for CMM and analyzes the current status and challenges faced by the formulation of international standards for CMM. Finally, this study puts forward the development strategy of international standards for CMM. Specifically, efforts should be made to develop top-level design with international market demands as the guidance and improve the quality of standards to accelerate the transformation of domestic high-quality standards into international standards. Moreover, measures should be taken to give full play to the positive role of enterprises in the formulation of standards, vigorously cultivate compound talents for international standardization of TCM, and constantly strengthen international cooperation. The experience and thinking are of guiding significance for the scientific, efficient and reasonable formulation of high-quality ISO standards for CMM in the future.

[Complete chloroplast genome of Ligustrum lucidum and highly variable marker identification for Ligustrum].

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.

Heterogeneous Genetic Diversity Estimation of a Promising Domestication Medicinal Motherwort Leonurus Cardiaca Based on Chloroplast Genome Resources.

Leonurus cardiaca has a long history of use in western herbal medicine and is applied for the treatment of gynaecological conditions, anxiety, and heart diseases. Because of its botanical relationship to the primary Chinese species, L. japonicus, and extensive medical indications that go beyond the traditional indications for the Chinese species, it is a promising medicinal resource. Therefore, the features of genetic diversity and variability in the species have been prioritized. To explore these issues, we sequenced the chloroplast genomes of 22 accessions of L. cardiaca from different geographical locations worldwide using high-throughput sequencing. The results indicate that L. cardiaca has a typical quadripartite structure and range from 1,51,236 bp to 1,51,831 bp in size, forming eight haplotypes. The genomes all contain 114 distinct genes, including 80 protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes. Comparative analysis showed abundant diversity of single nucleotide polymorphisms (SNPs), indels, simple sequence repeats (SSRs) in 22 accessions. Codon usage showed highly similar results for L. cardiaca species. The phylogenetic and network analysis indicated 22 accessions forming four clades that were partly related to the geographical distribution. In summary, our study highlights the advantage of chloroplast genome with large data sets in intraspecific diversity evaluation and provides a new tool to facilitate medicinal plant conservation and domestication.

[Research progress on medicinal resources of Coptis and its isoquinoline alkaloids].

Coptidis Rhizoma is a common Chinese medicinal in clinical practice,with the effects of clearing heat,drying dampness,purging fire,and removing toxin. All the medicinal plants of Coptis can be used for clinical treatment,but some species are endangered due to resource destruction and difficulty in planting. The dominant medicinal components in Coptidis Rhizoma are isoquinoline alkaloids. There are various methods for the analysis and detection of alkaloids,such as LC-MS,HPLC,and TLC,among which LC-MS is the most widely applied. Different plants of Coptis vary in the kind and content of alkaloids. C. chinensis,C. deltoidea,C. teeta,C. chinensis var. brevisepala,C. omeiensis,C. quinquefolia,and C. quinquesecta mainly contain berberine,palmatine,coptisine,jatrorrhizine,and columbamine,five effective alkaloid components. Plant isoquinoline alkaloids( PIAs) have strong pharmacological activity but are difficult to prepare. The application of synthetic biology of PIAs will be helpful for the clinical application of PIAs. This paper reviews the research progress on biological resources of Coptis species and structures of alkaloids as well as analysis methods and synthetic biology for isoquinoline alkaloids in the medicinal plants of Coptis in recent years,which will facilitate the protection of Coptis medicinal resources and the application and development of alkaloids.

[Molecular identification and alkaloids content of endangered Chinese medicinal plant Coptis chinensis var. brevisepala].

According to the records of Chinese materia medica,Coptis chinensis var. brevisepala is an authentic Chinese medicinal plant highly recommended by ancient physicians since its rhizome is like a string of beads and has a good medicinal value. However,its medicinal components and values remain to be studied as it is endangered because of overexploitation. Therefore,this study aims to quantitatively determine its effective components based on UPLC-QTOF-MS,and to compare the contents of isoquinoline alkaloids in C.chinensis var. brevisepala with those in other Coptis species. Meanwhile,molecular methods accurately identified 12 batches of C. chinensis var. brevisepala,9 batches of C. chinensis,4 batches of C. deltoidea,and 1 batch of C. teeta. Gradient elution was performed with Waters CORTECS C18 column( 4. 6 mm× 150 mm,2. 7 µm) and the mobile phase acetonitrile-water with 0. 4% formic acid. Mass spectrometry was conducted in ESI positive mode. The quantitative results showed that 8 main alkaloids had a good linear relationship within the concentration range( R~2>0. 996),with the recovery rate of 95. 18%-105. 0% and the RSD of 0. 28%-3. 7%. Compared with that of other Coptis species,the rhizome of C. chinensis var. brevisepala had the highest contents of berberine and columbamine. The total content of the 8 alkaloids in C. chinensis var. brevisepala was similar to that in C. chinensis but higher than that of the other two species. PCA was performed to compare the alkaloids among the 4 species. Besides,the 8 alkaloids were evaluated in different parts of C. chinensis var. brevisepala. The results indicate that this method is reliable and efficient and can provide a reference for the quality research.

[Current situation of nitrogen application and its effects on yield and quality of Chinese materia medica].

Nitrogen fertilizer has been the long-lasting crucial component in cultivation of Chinese materia medica(CMM) and crops for its profound effects on enhancing the productivity. In consideration of its role in better production, intensive and excessive application of N fertilizer is often found in CMM cultivation. Therefore, firstly, this review summarized various concentrations of N application with regards to different CMM and districts from the literatures published in the last two decades. The recommended concentration of nitrogen application of forty seven CMM species were covered in this review. We found that the optimum rates of nitrogen fertili-zer for different medicinal plants species were varied in the range between 0-1 035.55 kg·hm~(-2). Most of the optimum rates of nitrogen fertilizer for CMM in published researches fell between 100-199 kg·hm~(-2). The optimum rate of nitrogen fertilizer is not only related to amount of nitrogen required for different medicinal plants but also to soil fertilities of different fields. In addition, we outlined the diffe-rent effects of proper and excessive nitrogen deposition on yield of CMM. Proper nitrogen deposition benefits the yield of CMM, howe-ver, excessive nitrogen use accounts for a decrease in CMM yield. We elucidated that nutritional content, water use efficiencies, and photosynthesis capacity were major influencing factors. Researches showed that proper nitrogen fertilizer could promote the water use efficiencies of plants and boost photosynthesis. Consequently, the yield of CMM can be enhanced after nitrogen deposition. However, negative effects of nitrogen fertilizer were also found on plant including producing toxic substances to the soil and causing severe pest damages. Lastly we analyzed the impact of N fertilizer application on secondary metabolites which accounts for a large part of active pharmaceutical ingredients of CMM. It usually caused an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. The potential underlying mechanisms are the different synthetic pathways of these metabolites and the plant nutritional status. Synthesis of non-nitrogen-containing secondary metabolites like phenols can be inhibited after nitrogen application because of the competition of the same precursor substances between metabolites synthesis and plant growth. To sum up, impacts and mechanisms of nitrogen fertilizer on yield and quality enhancement of CMM were discussed in this review. Negative effects of excessive nitrogen application on CMM should be paid special attention in CMM cultivation and prescription fertilization based on the field soil quality is strongly recommended. Overall, this review aims to provides insights on improving the proper application of N fertilizer in the cultivation of CMM.

[Effects and mechanisms of nitrogen application on stress resistance of Chinese materia medica].

Nitrogen fertilizers play an important role in the regulation of plant stress resistance. Impacts of nitrogen fertilizers on abiotic stress resistance and biotic stress resistance of Chinese materia medica(CMM) were summarized in this study. Adequate nitrogen application improves the abiotic stress resistance and weed resistance of CMM, however adverse effect appears when excess nitrogen is used. Generally, pest resistance decreases along with nitrogen deposition, while effects of nitrogen application on disease resistance vary with different diseases. Mechanisms underlying the impact of nitrogen fertilizers on plant stress resistance were also elucidated in this study from three aspects including physical defense mechanisms, biochemistry mechanisms and molecular defense mechanisms. Nitrogen availability modulates physical barrier of CMM like plant growth, formation of lignin and wax cuticle, and density of stomata. Growth of CMM promoted by nitrogen fertilizer may cause some decrease in pest resistance of CMM due to an increase in hiding places for pest along with plant growth. High ambient humidity caused by excessive plant growth facilitates the growth and development of CMM pathogen. Nitrogen application can also interfere with the accumulation of lignin in CMM which makes CMM more vulnerable to pest and pathogen attack. Stomatal closing delays due to nitrogen application is also a causal factor of increasing pathogen infection after nitrogen deposition. Biochemical defenses of plants are mainly achieved through nutrient elements, secondary metabolites, defense-related enzymes and proteins. Nutritional level of CMM and various antioxidant enzymes and resistance-related protein activities are elevated along with nitrogen deposition. These antioxidant enzymes can reduce the damage of reactive oxygen species content produced by plant in response to adversity and therefore enhance stress resistance of CMM. Researches showed that nitrogen application could also cause an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. Nitrogen-mediated molecular defense mechanisms includes multiple plant hormones and nitric oxide signals. Plant hormones related to plant defense like salicylic acid, jasmonic acid and abscisic acid can be modulated by nitrogen application. Negative effect of nitrogen deposition was found on salicylic acid accumulation and the expression of related plant disease resistance genes. However, jasmonic acid level can be elevated by nitrogen. Nitric oxide signals constitute an important part of nitrogen mediated defense mechanisms. Nitric oxide signaling is related to many aspects of plant immunity. The roles of nitrogen fertilizers in CMM stress resistance are complex and may vary with different CMM varieties and environments. Further studies are urgently needed to provide a comprehensive understanding of how to improve stress resistance of CMM by using fertilizers.

Illumina Sequencing Reveals Conserved and Novel MicroRNAs of Dendrobium nobile Protocorm Involved in Synthesizing Dendrobine, a Potential Nanodrug.

Emergency of nanoparticulate drug delivery systems has improved the target, bioavailability, and curative effect of traditional Chinese medicine (TCM). However, the application of nano-preparation has been limited owing to the low content of active ingredients in part TCM. MicroRNAs (miRNAs) regulate plant growth, development, and response to environmental stresses at post-transcriptional regulation level by cleavage or translational inhibition. The molecular functions of miRNAs playing a role in synthesizing active comportments at medicinal plants have been widely researched. Dendrobium nobile is a perennial herb in the orchidaceae family. D. nobile protocorm can produce plant-specific metabolites at a short period. Therefore, it is a good substitute for producing metabolites. To understand the functions of miRNAs in D. nobile protocorm, Illumina sequencing of D. nobile protocorm (Dnp), D. officinale protocorm (Dcp), and D. nobile leaf (Dnl) were carried out. A total of 439, 412, and 432 miRNAs were identified from Dnp, Dcp, and Dnl, respectively. Some specific miRNAs were identified among them. Through combing GO and KEGG function annotation, miRNAs mainly involved metabolic pathways, plant hormone signal transduction, biological regulation, and protein binding. Acetyl-CoA acetyltransferase (AACT), mevalonate kinase (MK), 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR), and 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase (HDS), synthesizing basic precursor isoprene pyrophosphate (IPP) in terpenoid backbone biosynthesis pathway, were predicted as potential targets of 6 different miRNAs. Twenty-six miRNAs participated in auxin, cytokinin, abscisic acid, jasmonic acid, and salicylic acid signal transduction pathway. This report provided valuable candidate genes in Dnp involved in terpenoid biosynthesis and plant hormone signal transduction pathway. At the same time, it can help accelerate the use of dendrobine into nano preparation.

Chloroplast genome variation and phylogenetic relationships of Atractylodes species.

BACKGROUND: Atractylodes DC is the basic original plant of the widely used herbal medicines "Baizhu" and "Cangzhu" and an endemic genus in East Asia. Species within the genus have minor morphological differences, and the universal DNA barcodes cannot clearly distinguish the systemic relationship or identify the species of the genus. In order to solve these question, we sequenced the chloroplast genomes of all species of Atractylodes using high-throughput sequencing. RESULTS: The results indicate that the chloroplast genome of Atractylodes has a typical quadripartite structure and ranges from 152,294 bp (A. carlinoides) to 153,261 bp (A. macrocephala) in size. The genome of all species contains 113 genes, including 79 protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes. Four hotspots, rpl22-rps19-rpl2, psbM-trnD, trnR-trnT(GGU), and trnT(UGU)-trnL, and a total of 42-47 simple sequence repeats (SSR) were identified as the most promising potentially variable makers for species delimitation and population genetic studies. Phylogenetic analyses of the whole chloroplast genomes indicate that Atractylodes is a clade within the tribe Cynareae; Atractylodes species form a monophyly that clearly reflects the relationship within the genus. CONCLUSIONS: Our study included investigations of the sequences and structural genomic variations, phylogenetics and mutation dynamics of Atractylodes chloroplast genomes and will facilitate future studies in population genetics, taxonomy and species identification.

The complete chloroplast genome sequence of Sargentodoxa cuneata: genome structure and genomic resources.

Sargentodoxa cuneata is used as traditional Chinese medicine. In this study, we report its complete chloroplast genome by Illumina pair-end sequencing. The total chloroplast (cp) genome size was 158,094 bp in length, containing a pair of inverted repeats of 26,132 bp, separated by large single-copy and small single-copy regions of 86,508 bp and 19,322 bp, respectively. The chloroplast genome of S. cuneata encodes 113 different genes, including 79 protein-coding genes, 30 transfer RNAs, and 4 ribosomal RNAs. A total of 84 perfect chloroplast microsatellites were analyzed in the S. cuneata. The majority of the SSRs in this chloroplast genome are mononucleotides (66.67%). The reconstructed phylogeny revealed that S. cuneata was sister to the remaining Lardizabalaceae.

The complete chloroplast genome of Prunus japonica thunb.(Rosaceae), an ornamental and medicinal plant.

Prunus japonica is an ornamental and medicinal plant that is widely cultivated. The complete chloroplast genome of P. japonica was sequenced using Illumina Hiseq X Ten platform. The chloroplast genome was 158,080 bp in length, containing two short inverted repeat (IRa and IRb) regions of 26,385 bp, which was separated by a large single copy (LSC) region of 86,270 bp and a small single copy (SSC) region of 19,040 bp. The GC content of the whole chloroplast genome was 36.8%. The chloroplast DNA of P. japonica comprised 112 distinct genes, including 78 protein-coding genes, 4 ribosomal RNA genes and 30 transfer RNA genes. Phylogenetic analysis indicated that all species of Prunus formed a monophyletic group, P. japonica was closely related to P. hulimis.

Phylogenomic and evolutionary dynamics of inverted repeats across Angelica plastomes.

BACKGROUND: Angelica L. (family Apiaceae) is an economically important genus comprising ca. One hundred ten species. Angelica species are found on all continents of the Northern Hemisphere, and East Asia hosts the highest number of species. Morphological characters such as fruit anatomy, leaf morphology and subterranean structures of Angelica species show extreme diversity. Consequently, the taxonomic classification of Angelica species is complex and remains controversial, as the classifications proposed by previous studies based on morphological data and molecular data are highly discordant. In addition, the phylogenetic relationships of major clades in the Angelica group, particularly in the Angelica s. s. clade, remain unclear. Chloroplast (cp) genome sequences have been widely used in phylogenetic studies and for evaluating genetic diversity. RESULTS: In this study, we sequenced and assembled 28 complete cp genomes from 22 species, two varieties and two cultivars of Angelica. Combined with 36 available cp genomes in GenBank from representative clades of the subfamily Apioideae, the characteristics and evolutionary patterns of Angelica cp genomes were studied, and the phylogenetic relationships of Angelica species were resolved. The Angelica cp genomes had the typical quadripartite structure including a pair of inverted repeats (IRs: 5836-34,706 bp) separated by a large single-copy region (LSC: 76,657-103,161 bp) and a small single-copy region (SSC: 17,433-21,794 bp). Extensive expansion and contraction of the IR region were observed among cp genomes of Angelica species, and the pattern of the diversification of cp genomes showed high consistency with the phylogenetic placement of Angelica species. Species of Angelica were grouped into two major clades, with most species grouped in the Angelica group and A. omeiensis and A. sinensis grouped in the Sinodielsia with Ligusticum tenuissimum. CONCLUSIONS: Our results further demonstrate the power of plastid phylogenomics in enhancing the phylogenetic reconstructions of complex genera and provide new insights into plastome evolution across Angelica L.

The complete chloroplast genome of a medicinal plant, Abutilon theophrasti Medik. (Malvaceae).

Abutilon theophrasti Medik. is an annual weed, widely distributed in Asia and Europe. The complete chloroplast genome reported here is 160,446 bp in length, including two inverted repeats (IRs) of 25,064 bp, which are separated by a large single-copy (LSC) and a small single-copy (SSC) of 89,089 and 21,229 bp, respectively. The whole chloroplast genome of A. theophrasti contains 113 distinct genes, including 79 protein-coding genes, 30 transfer RNA, and four ribosome RNA. Phylogenetic analysis indicated that A. theophrasti is located in the basal position in Malveae.

Genetic Diversity and Phylogeography of the Important Medical Herb, Cultivated Huang-Lian Populations, and the Wild Relatives Coptis Species in China.

Huang-lian (Coptis plants in China) are essential medicinal plants in China, C. chinensis var. chinensis and C. deltoidea have been domesticated and cultivated for 700 years. In this study, the genetic diversity patterns and biogeographical information of cultivated Huang-lian and their wild relatives Coptis species were assessed using three plastids DNA regions. A total of 186 individuals from twenty-seven populations representing two species of cultivated Huang-lian and four species of wild relatives were collected and analyzed. Twenty-four haplotypes of six species were identified when three plastid spacers were combined. Historical biogeography inference revealed multiple dispersal events in the groups of cultivated Huang-lian and C. omeiensis. This evidence can infer that large initial population size and interbreeding with co-existing wild relatives in expanding new planting areas might be the main reason for maintaining the high genetic diversity of cultivated Huang-lian. Nevertheless, the multimodal curve of mismatch analysis and positive or negative differed among species and populations by neutrality tests indicated some groups of cultivated Huang-lian experienced genetic bottlenecks. Phylogeny analysis (NJ, MP, BI) showed that cultivated Huang-lian and C. omeiensis were clustered into a monophyletic group while C. chinensis var. brevisepala was paraphyletic, having earlier divergence time from C. chinensis var. chinensis (7.6 Ma) than C. omeiensis. Parsimony network demonstrated that C. deltoidea had more shared haplotypes with C. omeiensis than C. chinensis var. chinensis, and other haplotypes of C. deltoidea and C. omeiensis had less mutation steps than that of C. chinensis var. chinensis and C. omeiensis. This evidence suggests that C. omeiensis has a closer relationship with cultivated Huang-lian and might be a potential wild relative to C. deltoidea. The results reported here provide the baseline data for preserving genetic resources of Huang-lian and also evaluating the genetic impacts of long-term cultivation on medicinal plants, which could be instructive to future cultivation projects of traditional Chinese medicinal plants.

[Biological characteristics of wild Angelica sinensis seed].

Wild Angelica sinensis is almost endangered, studying the biological characteristics of wild A. sinensis seeds is helpful for varietal improvement and its conservation. This paper systematically studied the morphological structure, thousand seed weight, viability, storage and other basic biological characteristics of wild A. sinensis fruits and seeds, and focused on the germination of excised embryos,the development of embryo, the effects of the temperature,light and hormones on seed germination.The study found that:①The embryos are not fully developed when harvested, the initial germination rate was low, the embryos can develop. After 15 days of low temperature storage, the embryos can develop completely and the germination rate is significantly increased. These results show that wild A. sinensis seeds have no dormancy, and the low germination rate is due to the low maturity of wild A. sinensis seeds. ②The sui-table germination temperature of wild A. sinensis is 15-25 ℃,and the optimal temperature is 20 ℃. Light does not affect the germination of A. sinensis seeds.③The applicable concentration of GA_3 can promote seeds germination, IAA and 6-BA has no significant effect on germination.④The optimum storage condition is dry storage at 4 ℃. Wild A. sinensis seeds can be stored for 1.5 years and cultivated seeds can be stored for 1 year.During the introduction and conservation, the best treatment conditions were dry storage at 4 ℃ for 30 d and soaking seeds with 200 mg·L~(-1) GA_3, the germination rate can reach 86.7%.

[Genetic diversity and genetic structure evaluation of cultivated Chinese wolfberry (Lycium barbarum) based on microsatellite population genetics].

A total of 178 Chinese wolfberry individuals from 17 populations were detected by 7 pairs of SSR primers to evaluate genetic diversity and structure, using software GenALEx 6.5,NTSYS,STRUCTURE, the effects of cultivation on genetic diversity and structure were clarified aiming to find the strategies for genetic management and sustainable use. The results showed that the genetic diversity of cultivated Chinese wolfberry was low. The average number of alleles N_A, expected heterozygosity H_E, observed heterozygosity H_O, and Shannon's information index H' was 3.9, 0.443 7, 0.556 6, 0.788 1, respectively. STRUCTURE, UPGMA clustering and PCA test indicated that Chinese wolfberry varieties were severely intermixed but no differentiation among varieties. Mantel test showed no significant correlation between genetic distance and geographic distance. AMOVA analysis showed that genetic variation mainly occurred among individuals within the population(84.58%, P<0.001), and there was almost no genetic differentiation between varieties(3.63%, P<0.001) and between populations(11.79%, P<0.001). The cultivation has caused a significant decline in the genetic diversity of Chinese wolfberry, which may cause inbreeding decline. New germplasm resources should be sought from the wild to improve the existing cultivars. On the other hand, there are obvious homogenization and germplasm intermixing between cultivated varieties and populations. Meanwhile, Chinese wolfberry cultivars should be purified and prevented from flowing into the wild population, in case of causing pollution of the wild germplasm.

[Population characteristics and threatened of wild Angelica sinensis in Gansu province].

The study aims to investigate spatial distribution pattern and age structure of wild Angelica sinensis in Gansu province.Ten plots each with an area of 100 m2 were set and the spatial coordinates of all wild A. sinensis individuals were measured within each plot. Based on plant individual mapping data,we explored the spatial distribution pattern and its differences between different life history stages of wild A. sinensis in Gansu province by using nearest neighbor distance statistics. Correlation analysis were carried out to explore the relationship between spatial aggregation degree and topographic factors. We also distinguished individuals to three life history stages( i.e. seedlings,adults and boltings) and then test the differences among/between them using nonparametric test.(1)We found that the dominant spatial distribution pattern of wild A. sinensis population in Gansu was aggregated distribution. There was no significant correlation between spatial aggregation degree of wild A. sinensis and altitude,slope and aspect. There was no significant difference between the average distance from seedlings to their nearest bolting individuals; the average distance from adult individuals to their nearest seedlings was significantly larger than the average distance from adult individuals to their nearest adult individuals; and the average distance from bolting individuals to their nearest adult individuals was significantly smaller than the average distance from bolting individuals to their nearest bolting individuals.(2)The age structure was showed as a declining population,characterized by less seedlings and bolting individuals,while more adult individuals within population. The population characteristics of wild A. sinensis,characterized by aggregated distribution pattern and senescent type of age structure,are disadvantage to its population development. The factors,such as habitat specialization,human activities and intraspecific competition,which shapes the current population characteristics,may increase the threatened status of wild A. sinensis. We suggest to strengthen the protection of wild A. sinensis.