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Polygonatum falcatum is a perennial herb distributed in East Asia. We determined the characteristics of the complete chloroplast genome in P. falcatum for the first time, with a de novo assembly strategy. The chloroplast genome was 154,579bp in length harboring 87 protein coding genes, 38 tRNA genes and eight rRNA genes. It exhibits typical quadripartite structure comprising a large single-copy (LSC) (83,528bp), a small single-copy (SSC) (18,457bp) and a pair of inverted repeats (IRs) (26,297bp). Phylogenetic analysis of 16 chloroplast genomes from Asparagaceae reveals that the genus Polygonatum is a monophyletic group and that P. falcatum is clustered together with the congener, P. odoratum.

Angelica L. has attracted global interest for its traditional medicinal uses and commercial values. However, few studies have focused on the metabolomic differences among theAngelicaspecies. In this study, we analyzed volatile metabolites of fourAngelicaspecies (Angelica sinensis(Oliv.) Diels,Angelica biserrata(R.H.Shan & Yuan) C.Q.Yuan & R.H.Shan,Angelica dahurica(Hoffm.) Benth. & Hook.f. ex Franch. & Sav.,Angelica keiskeiKoidz.) by employing the widely targeted metabolomics based on gas chromatography–tandem mass spectrometry. A total of 899 volatile metabolites were identified and classified into sixteen different categories. On average, categorical abundances of volatile metabolites such as terpenoids, alcohol, ketone, and ester were higher inAngelica keiskeithan those in the other threeAngelicaspecies. The metabolomic analysis indicated that 7-hydroxycoumarin and Z-ligustilide were accumulated at significantly higher levels inAngelica sinensis, whereas the opposite pattern was observed for bornyl acetate. In addition, we found a high correspondence between the dendrogram of metabolite contents and phylogenetic positions in the four species. This study provides a biochemical map for the exploitation, application and development of theAngelicaspecies as medicinal plants or health-related dietary supplements.HighlightsEight hundred and ninety-nine volatile metabolites were identified in fourAngelicaspecies.Medicinal plants differed in the accumulation of volatile compounds:Angelica keiskeiis rich in bornyl acetate, whileAngelica sinensisis rich in 7-hydroxycoumarin and Z-ligustilide.Angelica keiskeiexhibited high diversity and abundance of effective volatile compounds, and demonstrated its profound potential for industrial applications.

Monitoring intraspecific diversity offers invaluable insights on conservation practices as the variation is the product of species evolution. Accordingly, the role of population genetic diversity has drawn great attention over the last century responding to the biodiversity loss induced by a series of anthropogenic changes. Orchids are one of the most diverse, yet ironically most rapidly disappearing plant groups due to the specialized habitat preferences. Thus, population-level genetic diversity studies may offer a powerful tool for orchid conservation programs. Using the 3 restriction site-associated DNA (3RAD) approach, 2,734 genome-wide single nucleotide polymorphisms (SNPs) were isolated. With the 2,734 SNPs, we investigated genetic diversity and population structure on 72 individuals of

Range-wide population studies of wide spread species are often associated with complex diversity patterns resulting from genetically divergent evolutionary significant units (ESUs). The compound evolutionary history creating such a pattern of diversity can be inferred through molecular analyses. Asparagus cochinchinensis, a medicinally important perennial herb, is in decline due to overharvesting in Korea. Eight A. cochinchinensis populations in Korea and three populations from neighboring countries (China, Japan and Taiwan) were examined using nine nuclear microsatellite loci and three chloroplast microsatellite loci to characterize molecular diversity patterns. The average within-population diversity was limited likely due to long-term bottlenecks observed in all eight populations. High pairwise FST values indicated that the populations have largely diverged, but the divergences were not correlated with geographic distances. Clustering analyses revealed a highly complex spatial structure pattern associated with two ESUs. Approximate Bayesian Computation (ABC) suggests that the two ESUs split about 21,000 BP were independently introduced to Korea approximately 1,800 years ago, and admixed in secondary contact zones. The two ESUs found in our study may have different habitat preferences and growth conditions, implying that the two genetically divergent groups should be considered not only for conservation and management but also for breeding programs in agricultural areas.

There is growing attention given to gene flow between crops and the wild relatives as global landscapes have been rapidly converted into agricultural farm fields over the past century. Crop-to-wild introgression may advance the extinction risks of rare plants through demographic swamping and/or genetic swamping. Malus sieversii, the progenitor of the apple, is exclusively distributed along the Tien Shan mountains. Habitat fragmentation and hybridization between M. sieversii and the cultivated apples have been proposed to be the causal mechanism of the accelerated extinction risk. We examined the genetic diversity pattern of eleven wild and domesticated apple populations and assessed the gene flow between M. sieversii and the cultivated apples in Kazakhstan using thirteen nuclear microsatellite loci. On average, apple populations harbored fairly high within-population diversity, whereas population divergences were very low suggesting likely influence of human-mediated dispersal. Assignment results showed a split pattern between the cultivated and wild apples and frequent admixture among the apple populations. Coupled with the inflated contemporary migration rates, the admixture pattern might be the signature of increased human intervention within the recent past. Our study highlighted the prevalent crop to wild gene flow of apples occurring in Kazakhstan, proposing an accelerated risk of genetic swamping.

There is growing attention given to gene flow between crops and the wild relatives as global landscapes have been rapidly converted into agricultural farm fields over the past century. Crop-to-wild introgression may advance the extinction risks of rare plants through demographic swamping and/or genetic swamping. Malus sieversii, the progenitor of the apple, is exclusively distributed along the Tien Shan mountains. Habitat fragmentation and hybridization between M. sieversii and the cultivated apples have been proposed to be the causal mechanism of the accelerated extinction risk. We examined the genetic diversity pattern of eleven wild and domesticated apple populations and assessed the gene flow between M. sieversii and the cultivated apples in Kazakhstan using thirteen nuclear microsatellite loci. On average, apple populations harbored fairly high within-population diversity, whereas population divergences were very low suggesting likely influence of human-mediated dispersal. Assignment results showed a split pattern between the cultivated and wild apples and frequent admixture among the apple populations. Coupled with the inflated contemporary migration rates, the admixture pattern might be the signature of increased human intervention within the recent past. Our study highlighted the prevalent crop to wild gene flow of apples occurring in Kazakhstan, proposing an accelerated risk of genetic swamping.

Distribution of genetic variation over time and space is relevant to demographic histories and tightly linked to ecological disturbances as well as evolutionary potential of an organism. Therefore, understanding the pattern of genetic diversity is a primary step in conservation and management projects for rare and threatened plant species. We used eight microsatellite markers to examine the level of genetic diversity, spatial structure, and demographic history of Plagiorhegma dubium, a rare myrmecochorous herb, populations sampled across northeast Asia and Siberia. We found low within-population genetic variation associated with historical bottlenecks. Although pairwise FST values were not much higher than the ones found in similar life form species, STRUCTURE and PCoA revealed a clear broadscale spatial pattern of genetic structure. Bayesian clustering (best K = 6) and PCoA identified three populations that are distinctive from neighboring populations in the Korean peninsula, which suggests potential units for conservation and management plans in Korea. MIGRATE-N and BAYESASS showed that both contemporary (0.003-0.045) and historical migration rates (2 × e-5-4.6 × e-4) were low. Our findings provide a good example, where genetic considerations should be integrated for conservation and management plans of rare and threatened species.

The taxonomy and phylogenetic relationships of related taxa are important for understanding the biology of a species. Also, spatial distribution of genetic variation may offer insights into history of range shifts and demographic changes. The genus Tamarix L. from the Old World is a taxonomically challenging group that has widely expanded its range in the recent past. We examined genomic diversity patterns and the taxonomic identities of Korean Tamarix species whose taxonomy has remained unresolved. We used a total of 1773 SNP data from genotyping by sequencing for 37 Tamarix plants representing two species; T. chinensis and T. ramosissima to infer species delimitation and the geographic distribution of genomic diversity. Clustering (STRUCTURE; PCA, neighbor joining) and phylogenetic tree results indicated that the two morphologically similar species T. chinensis and T. ramosissima are genetically distinct and the two Korean populations (Sihwa & Songdo) are clustered closely with T. chinensis. Approximate Bayesian Computation based hypothesis testing results suggested that one of the two Korean populations, Songdo might have primarily been derived from the native area, China, followed by range expansion to Sihwa with a secondary admixture event between an established population, Songdo, and a native population, Beijing.

The cognizing of connectivity among small mammal populations across heterogeneous landscapes is complicated due to complex influences of landscape and anthropogenic factors on gene flow. A landscape genetics approach offers inferences on how landscape features drive population structure. Through a landscape genetics approach, we investigated influences of geographical, environmental, and anthropogenic features on populations of Apodemus agrarius, the striped field mouse, the prime vector of hemorrhagic fever by a landscape genetic approach. We identified landscape features that might affect the population structure of striped field mice by analyzing microsatellite markers of 197 striped field mice from 21 populations throughout South Korea. We developed Maximum-likelihood population effects models based on landscape distances and resistance matrices and pairwise FST values for meta-populations of striped field mouse. We also conducted Mantel and partial Mantel tests to investigate geographic patterns of genetic similarities. In Mantel and partial Mantel tests, the FST was significantly correlated with all three models of movement; movement cost, Euclidian distance and least-cost distance, although the magnitudes of correlations varied. The 4 top-ranked models included three variables; temperature, precipitation and one human disturbance factor (population). We did not attain a significant effect for anthropogenic factors on genetic similarities among populations in the Korean striped field mouse, but we confirmed a significant association for genetic similarity with climatic features (temperature and precipitation).

Rosa kokanica is a deciduous shrub distributed in Central Asia. We determined the genomic characteristics of the complete chloroplast genome in R. kokanica with a de novo assembly strategy. The chloroplast genome was 156,802bp in length harboring 89 protein coding genes, 37 tRNA genes and eight rRNA genes. It exhibits typical quadripartite structure comprising a large single-copy (LSC) (85,899bp), a small single-copy (SSC) (18,773bp) and a pair of inverted repeats (IRs) (26,065bp). Phylogenetic analysis of 16 chloroplast genomes from Rosaceae revealed that the genus Rosa is a monophyletic group and the R. kokanica is clustered together with the congener, R. acicular.

We report a complete chloroplast genome sequence of Malus sieversii. The CP genome was 160,223 bp in length with a typical quadripartite structure. Length of large single-copy (LSC) was 88,334 bp, ...

Background The genus Hosta is a group of economically appreciated perennial herbs consisting of approximately 25 species that is endemic to eastern Asia. Due to considerable morphological variability, the genus has been well recognized as a group with taxonomic problems. Chloroplast is a cytoplasmic organelle with its own genome, which is the most commonly used for phylogenetic and genetic diversity analyses for land plants. To understand the genomic architecture of Hosta chloroplasts and examine the level of nucleotide and size variation, we newly sequenced four (H. clausa, H. jonesii, H. minor, and H. venusta) and analyzed six Hosta species (including the four, H. capitata and H. yingeri) distributed throughout South Korea. Results The average size of complete chloroplast genomes for the Hosta taxa was 156,642 bp with a maximum size difference of ~ 300 bp. The overall gene content and organization across the six Hosta were nearly identical with a few exceptions. There was a single tRNA gene deletion in H. jonesii and four genes were pseudogenized in three taxa (H. capitata, H. minor, and H. jonesii). We did not find major structural variation, but there were a minor expansion and contractions in IR region for three species (H. capitata, H. minor, and H. venusta). Sequence variations were higher in non-coding regions than in coding regions. Four genic and intergenic regions including two coding genes (psbA and ndhD) exhibited the largest sequence divergence showing potential as phylogenetic markers. We found compositional codon usage bias toward A/T at the third position. The Hosta plastomes had a comparable number of dispersed and tandem repeats (simple sequence repeats) to the ones identified in other angiosperm taxa. The phylogeny of 20 Agavoideae (Asparagaceae) taxa including the six Hosta species inferred from complete plastome data showed well resolved monophyletic clades for closely related taxa with high node supports. Conclusions Our study provides detailed information on the chloroplast genome of the Hosta taxa. We identified nucleotide diversity hotspots and characterized types of repeats, which can be used for developing molecular markers applicable in various research area.

Additional file 1: Table S1. The repeats shared by six Hosta species in Korea. The types are abbreviated as follows: F-forward, P-inverted (palindromic), C-complement, and R-reverse repeats. Table S2. The summary of the chloroplast genome sequences downloaded from GenBank for phylogenetic analysis. Table S3. Sample list used in the level of polymorphism test for the four hypervariable sites (ndhF-rpl32 IGS, ndhD, psbA, and trnL). No. refers to number. Spp. indicates species. Table S4. Variable sites found in the six Hosta species in Korea. The species acronyms are as following: CAP- H. capitata; CLA- H. clausa; JON-H. jonesii; MIN- H. minor; VEN- H. venusta; YIN- H. yingeri. Dashes represent indels. Figure S1. Gel image of size variation in trnK-UUU ~ trnQ-UUG region amplified for the six Korean Hosta species. The size of the PCR fragments was determined by electrophoresis using the QIAxcel Advanced System and QIAxcel ScreenGel Software (Qiagen). The 5000 bp and 15 bp reference markers are marked in green. Lane A, H. capitata; lane B, H. clausa; lane C, H. jonesii; lane D, H. minor; lane E, H. venusta; lane F, H. yingeri. bp refers to the base pair. R indicates the reference marker. Figure S2. Codon contents for the optimal codons, i.e. codons occurring significantly more often in highly expressed genes, encoding 20 amino acids in the six Hosta chloroplast genomes in Korea. RSCU denotes for relative synonymous codon usage. S1. The method of amplification for LSC and IRb border to examine 278 bp deletion in Hosta capitata. S2. The method of amplification to identify intraspecific sequence polymorphism for the four hypervariable sites (psbA, ndhD, trnL, and ndhF-rpl32 IGS) in the six Koran Hosta species.

Key message Genotyping data of a comprehensive Korean soybean collection obtained using a large SNP array were used to clarify global distribution patterns of soybean and address the evolutionary history of soybean. Abstract Understanding diversity and evolution of a crop is an essential step to implement a strategy to expand its germplasm base for crop improvement research. Accessions intensively collected from Korea, which is a small but central region in the distribution geography of soybean, were genotyped to provide sufficient data to underpin population genetic questions. After removing natural hybrids and duplicated or redundant accessions, we obtained a non-redundant set comprising 1957 domesticated and 1079 wild accessions to perform population structure analyses. Our analysis demonstrates that while wild soybean germplasm will require additional sampling from diverse indigenous areas to expand the germplasm base, the current domesticated soybean germplasm is saturated in terms of genetic diversity. We then showed that our genome-wide polymorphism map enabled us to detect genetic loci underlying flower color, seed-coat color, and domestication syndrome. A representative soybean set consisting of 194 accessions was divided into one domesticated subpopulation and four wild subpopulations that could be traced back to their geographic collection areas. Population genomics analyses suggested that the monophyletic group of domesticated soybeans was likely originated at a Japanese region. The results were further substantiated by a phylogenetic tree constructed from domestication-associated single nucleotide polymorphisms identified in this study. Electronic supplementary material The online version of this article (10.1007/s00122-018-3271-7) contains supplementary material, which is available to authorized users.

Human-driven habitat fragmentation leads to spatial isolation of endangered plant species, increasing extinction risk. An endangered medicinal herb, Aconitum austrokoreense, is a species with limited dispersal ability. Our molecular analysis revealed that within-population level genetic diversity is low, whereas the among-population divergence is high in this species. Moreover, several populations of A. austrokoreense might have experienced recent bottlenecks. The results suggested that the species might have declined and/or still decline in population size, resulting in increased extinction risk. Coupled with the life history traits such as dispersal and pollination, recent habitat fragmentation may further increase the extinction risk of the species., Human-driven habitat fragmentation leads to spatial isolation of endangered plant species increasing extinction risk. Understanding genetic variability and population structure of rare and isolated plant species is of great importance for assessing extinction risk and setting up conservation plans. Aconitum austrokoreense, an endangered and endemic species in Korea, is a perennial herb commonly used for medicinal purposes. We used five nuclear microsatellites and one chloroplast marker to investigate genetic diversity and population structure for 479 individuals of A. austrokoreense from seven populations throughout South Korea. A multivariate approach, discriminant analysis of principal components analysis, revealed broad-scale spatial patterns of A. austrokoreense populations across three major mountains that were composed of seven genetically distinct subgroups. High pairwise FST values (mean FST = 0.35; highest FST = 0.55) suggested significant differentiation among populations. Overall within population genetic variation was low. Based on Mantel test, there was significant correlation between geographical and genetic distances indicating pattern of isolation by distance. Our results suggest that A. austrokoreense populations may have undergone recent population bottlenecks. Given the limited dispersal ability of the species and ongoing habitat fragmentation, population isolation may further be exacerbated leading to increased extinction risk.

Understanding the complex influences of landscape and anthropogenic elements that shape the population genetic structure of invasive species provides insight into patterns of colonization and spread. The application of landscape genomics techniques to these questions may offer detailed, previously undocumented insights into factors influencing species invasions. We investigated the spatial pattern of genetic variation and the influences of landscape factors on population similarity in an invasive riparian shrub, saltcedar (Tamarix L.) by analysing 1,997 genomewide SNP markers for 259 individuals from 25 populations collected throughout the southwestern United States. Our results revealed a broad-scale spatial genetic differentiation of saltcedar populations between the Colorado and Rio Grande river basins and identified potential barriers to population similarity along both river systems. River pathways most strongly contributed to population similarity. In contrast, low temperature and dams likely served as barriers to population similarity. We hypothesize that large-scale geographic patterns in genetic diversity resulted from a combination of early introductions from distinct populations, the subsequent influence of natural selection, dispersal barriers and founder effects during range expansion.

Premise of the study Plagiorhegma dubium (Berberidaceae) has been listed as an endangered species in Korea due to extensive collection and destruction of natural habitats. In this study, 30 microsatellite loci, including 25 polymorphic loci, were developed for P. dubium for use in population-level genetic analyses. Methods and results We carried out transcriptome sequencing and isolated a total of 30 expressed sequence tag-simple sequence repeat markers from P. dubium using Illumina HiSeq high-throughput sequencing. To test utility of the developed markers, we genotyped 60 individuals from three populations and estimated the number of alleles and levels of observed and expected heterozygosity. Expected heterozygosity levels ranged from 0.000 to 0.594, 0.000 to 1.000, and 0.000 to 0.744 in the three populations, respectively. Conclusions These transcriptome-derived simple sequence repeat markers are highly polymorphic and can be widely used in characterization of the endangered P. dubium. Population genetic studies with these markers will provide valuable insights for conservation by unraveling evolutionary patterns of P. dubium.

In this paper, a robust self-tuning controller for a velocity control of permanent magnet type stepping motor is proposed‥ The self-tuning theory provides a nonlinear modeling of a stepping motor drive system and could provide the controller with information regarding the reference variation, system noise, and parameter variation of the stepping motor through the on-line estimation. Thus, the proposed self-tuning controller can change the gains of the controller according to system conditions. The availability of the proposed controller is verified through experiment results.