Skip to main content
Download PDF

Phylogeography of cultivated and wild ophiopogon japonicus based on chloroplast DNA: exploration of the origin and sustainable cultivation

BMC Plant Biology volume 23, Article number: 242 (2023) Cite this article

Abstract

Background

Ophiopogon japonicus, mainly planted in Sichuan (CMD) and Zhejiang (ZMD) province in China, has a lengthy cultivation history. During the long period of domestication, the genetic diversity of cultivated O. japonicus has substantially declined, which will affect the population continuity and evolutionary potential of this species. Therefore, it is necessary to clarify the phylogeography of cultivated O. japonicus to establish a theoretical basis for the utilization and conservation of the genetic resources of O. japonicus.

Result

The genetic diversity and population structure of 266 O. japonicus individual plants from 23 sampling sites were analyzed based on 4 chloroplast DNA sequences (atpB-rbcL, rpl16, psbA-trnH and rpl20-5’rps12) to identify the effects of domestication on genetic diversity of cultivars and determine their geographic origins. The results showed that cultivated O. japonicus and wild O. japonicus had 4 and 15 haplotypes respectively. The genetic diversity of two cultivars (Hd = 0.35700, π = 0.06667) was much lower than that of the wild populations (Hd = 0.76200, π = 0.20378), and the level of genetic diversity in CMD (Hd = 0.01900, π = 0.00125) was lower than that in ZMD (Hd = 0.06900, π = 0.01096). There was significant difference in genetic differentiation between the cultivated and the wild (FST = 0.82044), especially between the two cultivars (FST = 0.98254). This species showed a pronounced phylogeographical structure (NST > GST, P < 0.05). The phylogenetic tree showed that the genetic difference between CMD and ZMD was not enough to distinguish the cultivars between the two producing areas by using O. amblyphyllus Wang et Dai as an outgroup. In addition, both CMD and ZMD have a closer relationship with wild populations in Sichuan than that in Zhejiang. The results of the TCS network and species distribution model suggested that the wild population TQ located in Sichuan province could serve as the ancestor of cultivated O. japonicus, which was supported by RASP analysis.

Conclusion

These results suggest that cultivated O. japonicus has experienced dramatic loss of genetic diversity under anthropogenic influence. The genetic differentiation between CMD and ZMD is likely to be influenced by founder effect and strong artificial selection for plant traits. It appears that wild populations in Sichuan area are involved in the origin of not only CMD but also ZMD. In addition, we also raise some suggestions for planning scientific strategies for resource conservation of O. japonicus based on its genetic diversity and population structure.

Peer Review reports

Background

Phylogeography, which is a discipline concerned with various relationships between gene genealogies, phylogenetics and geography [1, 2], is often applied to compare the genetic lineages and current geographical distribution patterns of species to explore the historical processes and provide useful information for sustainable cultivation of plants. The currently DNA molecular marker techniques used in the analysis of plant phylogeography mainly include chloroplast DNA (cpDNA), nuclear DNA (nDNA) and simple sequence repeat (SSR). Although nDNA and SSR have a faster evolution rate than cpDNA and are inherited biparentally, a phenomenon termed concerted evolution has made nDNA more suitable for studying phylogeography among species [3], while the disadvantage of SSR easily losing some gene information in the process of mutation limits its application in phylogeography [4]. For cpDNA, the traits of uniparental inheritance and haploid enable it to preserve the genetic traces of plants in the long history process to a large extent. Besides, a shorter mean coalescent time gives cpDNA a greater advantage in calculating the time of ancestral differentiation [5]. Therefore, it is appropriate to use phylogeographic approaches based on cpDNA to understand the demographic and historical processes of medicinal plants and to further propose suitable conservation and sustainable cultivation practices for medicinal plants.

Ophiopogon japonicus (L. f.) Ker-Gawl., an evergreen perennial herb in the Liliaceae family. is a typical domesticated medicinal plant whose cultivation history can trace back to Song Dynasty. The tuberous root of O. japonicus has been used for the treatment of coughs, sore throats, thirstiness, insomnia and constipation in traditional Chinese medicine (TCM) over 2000 years due to its functions in nourishing Yin, promoting the production of body fluid, moistening lungs and clearing away internal heat [6]. Zhe maidong (ZMD) and Chuan maidong (CMD) are two genuine cultivars of O. japonicus in China planted in Zhejiang and Sichuan respectively. Different geographical locations led to the different growing environment of the two cultivars [7]. Despite these external factors, CMD and ZMD have had stable mutation loci in cpDNA and nuclear genome [7, 8]. All these phenomena may cause different chemical constituents [9,10,11] and pharmacological activities [12,13,14] between ZMD and CMD, which would play pivotal roles in recognizing a superior clinical efficacy of ZMD over CMD. However, previous studies revealed that the genetic diversity of O. japonicus has decreased a lot which will affect the long-term survival and evolutionary potential of this species, and then affect the selection and breeding of high-quality medicinal herbs [15, 16]. Hence, further evaluation of the genetic diversity and location of the original site of cultivated O. japonicus are essential for designing strategies of protecting the genetic resources and breeding new varieties.

To provide practical information necessary for origin exploration and sustainable cultivation of O. japonicus, we used 4 chloroplast DNA regions (atpB-rbcL, rpl16, psbA-trnH and rpl20-5’rps12) to figure out the population genetics and phylogeography of wild and cultivated O. japonicus. More specific objectives are to (1) evaluate the genetic diversity of cultivated populations under artificial selection and wild populations, and determine which wild populations can be introduced for the improvement of cultivation; (2) clarify the genetic divergence between cultivated populations of O. japonicus from Sichuan province and Zhejiang province; and (3) disclose the geographical origins and ancestral populations of cultivated O. japonicus.

Results

Genetic diversity and differentiation of O. japonicus

One cpDNA intron (rpl16) and three cpDNA spacers (atpB-rbcL, psbA-trnH and rpl20-5’rps12) were chosen to analyze the genetic variation in O. japonicus from different geographical locations after preliminary variation screening. Based on 266 individuals representing 23 populations of O. japonicus, the nucleotide sequence length was 698 bp, 523 bp, 479 and 708 bp for the atpB-rbcL, rpl16, psbA-trnH and rpl20-5’rps12 regions, respectively. The combined cpDNA sequence length after multiple alignments was 2408 bp. In total, 107 polymorphic sites and 19 haplotypes were detected from 10 cultivated populations and 13 wild populations of O. japonicus. The variation rate of the combined cpDNA sequence was 4.44%, and the aligned sequence variations are summarized in Additional file 1.

Genetic diversity of O. japonicus was estimated by the number of haplotypes (H), haplotype diversity (Hd) and nucleotide diversity (π) in O. japonicus (Table 1). 19 haplotypes were obtained from 23 populations, including 4 haplotypes from cultivated O. japonicus and 15 haplotypes from wild O. japonicus (Fig. 1). The Hd and π at the species level of O. japonicus were 0.74500 and 0.00712 respectively. The Hd and π of CMD (0.01900; 0.00006) were lower than those of ZMD (0.06900; 0.00049) and wild populations (0.76200; 0.00905). Furthermore, the result of permutcpSSR showed that the genetic diversity of all 13 wild populations (hT = 0.849, hS = 0.341, VT = 0.859, VS = 0.204) was much higher than that of the two cultivars (hT = 0.521, hS = 0.030, VT = 0.842, VS = 0.067).

According to the AMOVA analysis (Table 2), genetic differentiation of cultivated O. japonicus occurred mainly between the two cultivars (95.51% among populations in the nonhierarchical AMOVA analysis of cultivated, and 98.37% among groups in the hierarchical AMOVA analysis of CMD vs. ZMD), which is different from wild O. japonicus whose variation mainly occurred among populations (70.09%). Comparison of different groups showed huge genetic variations between CMD and ZMD (98.37%), which is consistent with the low gene flow between the two cultivars (Nm =0.04). The results suggest that there had been a high genetic differentiation between CMD and ZMD. What’s more, the percentage of genetic variation between CMD and wild group (40.30%) was much higher than that between ZMD and wild group (8.64%), because the gene flow between ZMD and wild group (Nm = 1.490) can resist genetic differentiation caused by genetic drift among populations between ZMD and wild groups (FST = 0.72934), while the gene flow between CMD and wild group (Nm = 0.830) was insufficient to resist the genetic differentiation caused by migration or genetic drift between CMD and wild group (FST = 0.82566).

Fig. 1
figure 1

 A geographic distribution of 19 cpDNA haplotypes (H1-H19) detected in O. japonicus

Full size image
Table 1 Genetic diversity analysis based on cpDNA of O. japonicus
Full size table
Table 2 Analysis of molecular variance (AMOVA) based on the cpDNA sequences
Full size table

Population structure and phylogeographical analysis

A permutation test showed that NST was significantly higher than GST (NST/GST = 0.920 /0.753, P < 0.01), indicating that geographically close haplotypes were distributed in the same or contiguous population. And the genetic differentiation among population increased with the increase of geographical distance, indicating that there was a significant phylogeographic structure in O. japonicus cpDNA haplotypes. Mantel test, in which only wild populations were included, also supported the result that the genetic distances between O. japonicus populations were significantly and positively correlated with their geographical distances (P = 0.05, R2 = 0.111). With the increase of geographical distance, the genetic distance of O. japonicus also showed a trend of increase (Fig. 2). Combined with the low gene flow among populations of O. japonicus (Nm = 0.17), this species showed a pattern of restricted gene flow with isolated by distance.

Fig. 2
figure 2

Mantel test of relationship between genetic distance and geographical distance among populations of O. japonicus

Full size image

The phylogenetic relationships between the 19 cpDNA haplotypes were assessed under Bayesian inferences drawn using O. amblyphyllus Wang et Dai (H20) as an outgroup. The result showed that the phylogenetic tree of the 19 cpDNA haplotypes had a comb-like structure (Fig. 3). Haplotypes (H1, H2, H3 and H4) from cultivated populations occurred in different clades, but still grouped together compared with the outgroup. As a result, we could not distinguish CMD from ZMD based on the 4 cpDNA sequences.

Furthermore, the rooted TCS network of cpDNA haplotypes revealed the relationship of the interior (ancestral) and the tip (derived) haplotypes (Fig. 4). H13, the haplotype only found in the TQ population, was inferred as the ancestral haplotype because it lies at the center of TCS network and is connected with other derivative haplotypes. 4 cpDNA haplotypes (H1, H2, H3 and H4) were found within the cultivated populations and all of them came from H13. Among them, H1 was the most frequent and widely distributed haplotype and shared between CMD and wild O. japonicus; H3 was shared between ZMD and wild O. japonicus; H2 was shared only by CMD; and H4 was shared only by ZMD. The other 15 haplotypes were found only in wild populations. The haplotype distribution also confirmed the low genetic diversity of cultivated O. japonicus.

Fig. 3
figure 3

Maximum-likelihood (ML) phylogenetic tree: the number showed on nodes stands for the bootstrap value on 1000 replicates; O. amblyphyllus Wang et Dai is set as an outgroup

Full size image
Fig. 4
figure 4

Minimum spanning network of 19 cpDNA haplotypes in O. japonicus. The network was rooted at the O. amblyphyllus Wang et Dai. The circle size is proportional to the number of samples per haplotype. Hollow dots indicate the number of mutational steps

Full size image

Demographic history

The mismatch distribution for O. japonicus was clearly multimodal and inconsistent with the bell-shaped curve expected for an expanding population at species level (SSD = 0.10627, P = 0.000 < 0.05), suggesting that O. japonicus did not undergo a recent expansion in the face of favorable climatic and environmental conditions (Fig. 5). Neither did the wild population of O. japonicus expand recently (SSD = 0.08589, P = 0.000 < 0.05). However, CMD whose SSD-value was 0.00028 (P = 0.058 > 0.05) and ZMD whose SSD-value was 0.00401 (P = 0.160 > 0.05) had a relatively smooth unimodal distribution, suggesting that CMD and ZMD could be assumed as an expansion model.

At the species level, both Tajima’s D (-0.03985, P = 0.799) and Fu’s Fs (20.36184, P = 0.926) showed no significant difference from zero, indicating O. japonicus had not passed through a recent demographic expansion. Neither did the wild populations undergo expansion recently (Tajima’s D = 0.60829, P = 0.732; Fu’s Fs = 20.39273, P = 1.000). However, the value of Tajima’s D and Fu’s Fs (Table 1) implied that demographic expansion existed in certain populations from CMD and ZMD, which is consistent with the result of mismatch distribution.

Fig. 5
figure 5

Mismatch distribution for cpDNA sequence data in O. japonicus. The red line represents the expected values and blue line represents the observed values

Full size image

Historical biogeography

The results of S-DIVA ancestral area reconstruction based on RASP suggested that O. japonicus may originate in Sichuan (A) with subsequent dispersal and vicariance events between the ancestral and areas of present distribution (Fig. 6). These facts support that Sichuan may be an ancestral area of O. japonicus.

Fig. 6
figure 6

Historical biogeography of O. japonicus. (a) The ancestral area reconstruction results based on RASP of O. japonicus. The pie charts on nodes display the relative probabilities of possible ancestral ranges. (b) The map showing five geographical regions in colors as defined in RASP analysis.

Full size image

Species distribution modeling

Based on the geographical distribution of O. japonicus, MaxEnt was used to simulate the potential distribution of O. japonicus during LIG, LGM, MID and present (Fig. 7). The AUC score, which represents the average of 10 runs, was higher than 0.8 for the four models built, which supports their predictive power [17].

The simulation results of species distribution showed that O. japonicus distributed in most areas of China during the LIG period (Fig. 7-A). After the LGM period, the distribution ranges of the species had a slight expansion or recolonization in the geographical range (Fig. 7-C). While the distribution range of O. japonicus at present is similar to that of MID (Fig. 7-D), indicating that the migration and expansion of O. japonicus at MID tend to be basically stable.

Fig. 7
figure 7

Simulation of the distribution area of O. japonicus in different climatic conditions in China

Full size image

Discussion

Genetic diversity and differentiation

For many cultivated crops, artificial selection, founder effect and genetic bottleneck may consequently reduce their genetic diversity [18,19,20], as well as their capacity for long-term survival and evolution in dynamic environments. Due to the comparatively brief domestication period and the exchange of genes with wild populations during extensive cultivation, the genetic diversity of medicinal plants has declined in a much milder manner as compared with the crops. In our fieldwork, we investigated 13 sites of wild O. japonicus, 7 CMD cultivation bases in the villages along Fujiang River in Sichuan province and 3 ZMD cultivation bases, 2 of which are situated in the traditional genuine producing area Cixi and the other is located in new producing area Santai. The present study demonstrated that cultivated O. japonicus had undergone a striking decrease in genetic diversity (hT = 0.521, hS = 0.030, VT = 0.842, VS = 0.067) compared with the wild populations (hT = 0.849, hS = 0.341, VT = 0.859, VS = 0.204) after domestication for several hundred years. Of the 19 cpDNA haplotypes in the species, only 4 haplotypes were detected in cultivated populations. The domestication result of decreased genetic diversity is similar to that of Scrophularia ningpoensis [21] and Angelica dahurica [22]. These dramatic changes in the genetic diversity of O. japonicus during such a short domestication history are most likely caused by founder effect and the clonal mode of reproduction. Firstly, the founder effect is that when a population is established and developed by a small number of individuals, the genetic information carried by these few individuals does not completely reflect the genetic information of their source population, resulting in a low genetic diversity of the new population. The loss of genetic diversity for medical plants like Allium mongolicum [23], Leonurus cardiaca [24] and Lycium barbarum [25] is more or less related to the founder effect. In this study, we only gathered 2 haplotypes of cultivated O. japonicus from the haplotypes of wild populations due to the founder effect, meaning that the founders contained only a few samples of the wild populations with certain genetic information. Secondly, although the domestication history of O. japonicus was shorter than other medical plants like Coix lacryma-jobi L. and Carthamus tinctorius L. [26], the genetic diversity of cultivated O. japonicus was dramatically decreased because wild O. japonicus could expand via fruits while cultivated O. japonicus was influenced by asexual reproduction and artificial selection. In addition, previous studies have demonstrated that genetic bottlenecks caused by domestication in annual and perennial fruit crops, suggesting that perennial crops can preserve a higher percentage of the genetic variation present in their wild progenitors than annual crops [27]. And juvenile phase length is a principal difference between domesticated annual and domesticated perennial fruit crops. In this study, the cultivation time before harvest was 2 or 3 years for ZMD and 1 year for CMD. ZMD (Hd = 0.06900; π = 0.00049) showed a higher genetic diversity than CMD (Hd = 0.06900; π = 0.00049). And the gene flow of ZMD-wild (Nm = 1.490) was higher than that of CMD-wild (Nm = 0.830), implying that the relatively lengthy juvenile phases coupled with ongoing cultivar–wild gene flow due to the change of habitat may contribute to the milder genetic bottlenecks in perennial ZMD than annual CMD, resulting in relatively high genetic diversity in ZMD.

In addition to reducing the genetic diversity of medical plants, domestication also affects the structural patterns of genetic variations [28]. For instance, notable genetic divergence was found between wild and cultivated Angelica dahurica and between its two cultivars (Fct = 0.148, P = 0.000) [22]. Our result of AMOVA analysis indicated that 21.8% of the total genetic variation occurred between cultivated and wild O. japonicus, while 98.37% of the total genetic variation occurred between CMD and ZMD (Table 2). Further analysis revealed that the genetic differentiation between ZMD and wild O. japonicus (FST = 0.72934) was lower than that between CMD and wild O. japonicus (FST = 0.82566). The results of mismatch distribution and neutrality test indicated that both ZMD and CMD had undergone a recent population expansion. Frequent extinctions and recolonizations of local populations can also be an important source of gene flow[29]. It has been reported that ZMD production areas have experienced significant changes in recent years [30]. Due to urbanization and regional economic reasons, most farmers in the traditional production area of ZMD (Hangzhou) no longer plant ZMD. Sanmen County, located in Taizhou City, Zhejiang province, has gradually became a new producing region of ZMD. As a result, it is probable that one of the factors contributing to the higher gene flow between ZMD and wild populations (Nm = 1.490) than between CMD and wild populations (Nm = 0.830) is the shrinkage of traditional production regions and the creation of new production areas. In a group of completely isolated populations, genetic drift tends to fix different alleles in different local populations. Genetic drift is the unpredictable change in gene frequency due to finite population size. Gene flow between any populations will prevent complete fixation, but gene flow must exceed a certain level (Nm > 1) to prevent substantial genetic differentiation due to genetic drift [29]. This also clarifies why the gene flow between ZMD and wild populations (Nm = 1.490) is able to withstand the genetic differentiation caused by genetic drift while the gene flow between CMD and wild populations (Nm = 0.830) is unable.

As for the genetic differentiation between CMD and ZMD, on the one hand, we believe that it is the result of artificial selection and the isolation by distance. Our surveys conducted in the cultivated regions indicated that seedlings of CMD are prostrate CMKY-2, whereas the seedlings of ZMD are mainly erect O. japonicus with a small number of prostrate O. japonicus [31]. This combination of artificial selection and clonal propagation of O. japonicus rapidly fixes the alleles carried by selected individuals, which means that one or two haplotypes are fixed in each cultivar population, leading to large genetic differences between ZMD and CMD. In addition, the herbal textual studies and the description of the local planters exhibited that there was no record about the introduction of one cultivar of O. japonicus into another cultivar’s growing region, which may have prevented gene flow and then leading to the genetic differentiation between CMD and ZMD. Finally, population differentiation is also influenced by geographical distance. Isolation by distance is a model of the population structure in which genetic differences between populations increase with the geographic scale [32]. In other words, populations adjacent to each other share more similarities than those growing far apart, because they are linked by larger gene exchange, unless some impassable isolation breaks this mechanism and reduces the communication between some populations and their neighbors. Our results showed that a greater NST (0.920) than GST (0.753), indicating the presence of the phylogeographical structure of O. japonicus. Combined with the result of mantel test, it can be inferred that the restricted gene flow with isolated by distance contribute to the population structure of O. japonicus [33]. Geographical isolation can contribute to the lack of gene flow among populations leading to the genetic differentiation between two cultivars.

Origin of cultivated O. japonicus

Designing strategies for the protection of genetic resources and the breeding of new varieties can be assisted by identifying the original site of domestication and evaluating the evolution history of wild-domesticated species [34]. Before Tang Dynasty, O. japonicus was believed to come from the wild species and be mainly distributed in Henan, Jiangsu, Zhejiang and Anhui provinces. ZMD and CMD cultivation can trace back to Song Dynasty and Ming Dynasty respectively [35]. As the first study exploring the origin of O. japonicus, we explored the ancestral distribution of O. japonicus and its historical changes based on 4 chloroplast DNA data. ML phylogenetic tree in this study showed that ZMD and CMD were grouped as a cluster as compared with the outgroup (Fig. 3). Further studies found ZMD and some individuals in the wild population BZ located in Sichuan were grouped as a cluster, while CMD and the wild population NC located in Sichuan were grouped as another cluster. These results suggest that the cultivated O. japonicus is more closely linked to wild populations in Sichuan than the wild O. japonicus in Zhejiang, which is similar to the study on the genetic diversity of cultivated O. japonicus based on ISSR markers [15]. Therefore, the wild populations NC and BZ located in Sichuan province may have played an important role in the origin of cultivated O. japonicus.

The TCS network claimed that 2 haplotypes (H1 and H2) found in CMD and 2 haplotypes (H2 and H4) found in ZMD were derived from H6 and H13 respectively. The 2 haplotypes (H6 and H13) both found only in the wild population BZ and TQ located in Sichuan province. All of the aforementioned haplotypes were derived from H13, which lied at the center of the haplotype network and was only found in the wild population TQ located in Sichuan. It may be the ancestor of the two cultivars in this study. Furthermore, as the most frequent and widely distributed haplotype, H1 was found not only in CMD but also in the wild population NC, while H3, which occurred in most ZMD, was also found in the wild population BZ, suggesting that the wild populations in Sichuan contributed more to the origin of O. japonicus.

The result of historical biogeography and the model of species distribution indicated that O. japonicus distributed in most areas of China during LIG period (Fig. 7-A). But the cold climate deprived the previously hospitable environment of this species, leading to a large-scale migration. O. japonicus migrated to the east of Hengduan Mountains and south of Qinling Mountains (Fig. 7-B), suggesting that these mountains may have been the refuge of this species during LGM. The ancestor of O. japonicus was located in Sichuan at that time, and then experienced multiple vicariance and dispersal processes between Sichuan and Zhejiang due to the emergence of suitable climatic conditions after LGM. This may explain why haplotypes H5 appeared in different populations located in Sichuan, Zhejiang, Hubei, Hunan, Guizhou and other provinces. In addition, the glacial refugium hypothesis (GRH) proposes that glaciers promoted differentiation and generation of intraspecific diversity by isolating populations in ice-free refugia [32], which was also supported by the results of haplotype diversity, geographical analysis and historical biogeography.

In summary, O. japonicus was widely distributed in China during the LIG period. With the passage of time, the cold climate caused O. japonicus to migrate to the east of Hengduan Mountains and south of Qinling Mountains during the LGM period. The present distribution was formed after several vicariance-dispersal events on the basis. More importantly, wild populations similar to the extant TQ located in Sichuan province may be the ancestor of cultivated O. japonicus.

Sustainable cultivation of O. japonicus

Wild populations have been considered as critical resources for breeding medical plants because their genetic information are used infrequently and generally exhibit no reproductively isolation from cultivated populations [36]. Our study compared cultivated and wild populations of O. japonicus indicated that cultivated O. japonicus had much lower genetic diversity than wild populations (Fig. 1; Table 1). The large-scale cultivation of O. japonicus has affected the genetic diversity of wild populations. For example, the wild population NC showed a single and identical haplotypes (H1) to CMD, which may reduce the plasticity of cultivated O. japonicus to respond to changes in climate, pathogen populations, agricultural practices, or quality requirements. Hence, it is necessary to improve the genetic diversity of cultivated O. japonicus through sexual reproduction by using wild resources.

Accumulative evidence indicates that a proper assessment of genetic resources of medicinal plants can provide useful information for the development of conservation plans to protect genetic diversity. For example, protection of medicinal plants like Angelica dahurica [22], Aspidopterys obcordata var. obcordate [37] and Vitex rotundifolia [38] were mostly based on the conservation of genetic diversity. Our study exhibited that wild populations DZ, HC and BZ had more cpDNA haplotypes and higher genetic diversity (Hd = 0.83300, π = 0.00568; Hd = 0.80300, π = 0.01341; Hd = 0.70500, π = 0.00488) than other populations (Fig. 1; Table 1). In addition, populations located in glacial refugia should be considered the priority for conservation because they not only preserve the genetic differentiation of species during the period of climate upheaval, but also serve as the starting point for post-glacial re-dispersal of species which can continue to maintain the continuity of genetic diversity [39,40,41]. The ENM results suggested that the east of Hengduan Mountains and south of Qinling Mountains were the glacial refugia of O. japonicus during LIG. RASP analysis indicated that the ancestor of O. japonicus was in Sichuan. These results demonstrated that Sichuan should be the starting point for post-glacial re-dispersal of O. japonicus. In summary, populations DZ, HC and BZ with high genetic diversity and populations TQ and BZ located in Sichuan with high genetic diversity should serve as key objects for biodiversity protection of O. japonicus and preferentially selected as the gene pool for improving the genotypes of cultivated O. japonicus.

Conclusion

In this study, we accessed the level of genetic structure of O. japonicus from 23 sampling sites by using 4 maternally inherited cpDNA primers and investigated the origin of O. japonicus for the first time. The result showed that it was the anthropogenic influence that led to the low genetic diversity and a high degree of genetic differentiation of O. japonicus from two producing areas as well as the high degree of genetic differentiation between the cultivated and wild populations. In terms of the origin, Sichuan may be one of the origins of O. japonicus, and the wild populations TQ in Sichuan area were recognized as the ancestor of cultivated O. japonicus. In addition, we postulate that the populations containing high genetic diversity (DZ, HC and BZ) and populations distributing in glacial refugia with high genetic diversity (TQ and BZ) should be protected for the conservation of genetic resource and improvement of genetic diversity for O. japonicus. Our findings may help better understand the influence of domestication on genetic diversity of medicinal plants and provide genetic insights into conservation and sustainable cultivation of O. japonicus.

Materials and methods

Plant material and DNA extraction

A total of 266 individual O. japonicus plant samples were obtained from 23 sites of different distribution areas of China for cpDNA analysis (Fig. 8; Table 3). The plants from which leaves were collected were apart from each other for more than 20 m to avoid overlapping clones (genotypes). The leaf samples were dried in silica gel and then stored in a freezer (− 20℃) for use. A sample of O. amblyphyllus Wang et Dai from Sichuan was also collected as the outgroup. Genomic DNA was extracted using the Plant Genomic DNA kit (Tiangen Biotech, Beijing, China). For the wild and cultivated plants we used in this study, we obtained relevant permission to collect. All voucher specimens were morphologically identified by Professor Luping Qin from the College of Pharmaceutical Sciences, Zhejiang Chinese Medical University (ZCMU) and deposited at the herbarium of ZCMU (voucher ID numbers: 510000190328LY001-510000190328LY013; 330000190630LY001-330000190630LY009; 520000200602LY001; 430000200527LY001; 420000200530LY001). Our field study and experimental research complied with local legislation, national and international guidelines.

Table 3 Details of sample locations and sizes
Full size table
Fig. 8
figure 8

Sample locations of O. japonicus used in this study

Full size image

cpDNA sequencing

Polymerase chain reaction (PCR) was performed in an Veriti96 thermocycler (Thermofisher). The primers unsed in this study are atpB-rbcL (F: GTG GAA ACC CCG GGA CGA GAA GTA GT; R: ACT TGC TTT AGT TTC TGT TTG TGG TGA), rpl16 (F: GAT GGC GGA ATG AAC CAA GA; R: CGT ACC CAT ATT TTT CCA CCA CGA C), psbA-trnH (F: ACT GCC TTG ATC CAC TTG GC; R: CGA AGC TCC ATC TAC AAA TGG) and rpl20-5’rps12 (F: TTT GTT CTA CGT CTC CGA GC; R: GTC GAG GAA CAT GTA CTA GG). The reaction mixture (50 µL) contained 2 µL of total DNA, 1 µL of each primer, 21 µL of ddH2O, and 25 µL of 2× Trans Taq High Fidelity (HiFi) PCR SuperMix (Transgen Biotech, Beijing, China). Double-stranded DNA was amplified after 4-min incubation at 94℃; followed by 30 cycles at 94 ℃ for 50 s, 54℃ for 50 s, and 72 ℃ for 90 s; with a final extension at 72 ℃ for 7 min. PCR products were identified on 1.0% agarose gels, visualized with ultraviolet light and photographed by using DNA Marker DL2000 (Takara Bio Inc.). The PCR products with a single band were cleaned by a EasyPure PCR Purification Kit (TransGen Biotech. Beijing, China) for direct sequencing. Sequencing was conducted from both ends.

Phylogenetic analyses

Geneious Pro V4.8.3 [42] was used to trim, assemble and align the DNA sequences. Bayesian phylogenetic analyses was performed on MrBayes 3.2.4 [43] to construct the phylogenetic tree based on the combined cpDNA data. The sequence evolution model T92 + G was evaluated by the Akaike Information Criterion (AIC) in Modeltest 3.7.0 [44]. Two independent analyses with four simultaneous Monte Carlo Markov Chains (MCMC) analyses were run for 10 million generations, with sampling done every 100 generations. The first 50,000 sampled trees were discarded as burn-in samples. A statistical parsimony haplotype network estimated the genetic relationships among haplotypes was built using TCS 1.21 [45].

Population genetic diversity and genetic differentiation

The number of haplotypes (H), haplotype diversity (Hd) and nucleotide diversity (π) of O. japonicus were computed by DnaSP v5.10 [46]. The program PermutCpSSR_1.2.1 [47] was used to calculate the average within-population gene diversity (hS), total gene diversity (hT) and the level of population differentiation at the species level (GST), as well as the geographical total haplotype diversity (VT), geographical average haplotype diversity (VS) and an estimate of population subdivisions for phylogenetically ordered alleles (NST) obtained by taking into account the similarities between haplotypes. GST and NST were used to assess the geographical structure that affected population differentiation. To evaluate the existence of correlation between the geographic and genetic distances, Mantel test was performed using GenAlEx v.6.502 [48]. The geographic distance matrix was constructed in Geographic Distance Matrix Generator v.1.2.3 [49], while the genetic distance matrix was constructed in Mega v.6.06 [50].

Demographic history

Mismatch distribution analysis was performed using the DnaSP v5.10 to develop figures and Arlequin 3.5 to calculate the values of the sum of squared deviations (SSD). The lack of significant differences in the SSD values indicated that the population assumed an expansion model.

The neutrality tests (Tajima’s D and Fu’s Fs) were carried out on Arlequin 3.5 [51]. Negative Tajima’s D values suggest that a population has recently increased in size, whose results can tell the bottlenecks, selective effects, population expansion, or heterogeneity of mutation rates of O. japonicus.

Biogeographic analysis

The statistical dispersal-vicariance analysis (S-DIVA) was implemented to infer ancestral distribution using RASP 3.2 [52]. The trees previously constructed by MrBayes were used as the input data. The geographical distribution of the species was categorized into five areas: (A) Sichuan province, China; (B) Zhejiang province, China; (C) Hubei province, China; (D) Hunan province, China; and (E) Guizhou province, China.

Ecological niche modeling (ENM)

19 bioclimatic variables at a resolution of 2.5 arc minutes were obtained from the WorldClim website (available at http://www.worldclim.org/download), and community climate system model version 4 (CCSM4) model simulation was selected in Last inter-glacial (LIG), Last Glacial Maximum (LGM) and Mid Holocene (MID) periods. The current distribution information for O. japonicus was obtained from major databases and information systems, including the Global Biodiversity Information Facility (GBIF; http://www.gbif.org/) and the Chinese Virtual Herbarium (http://www.cvh.ac.cn). After a pairwise correlation analysis using SPSS, we selected a smaller set of nine relatively uncorrelated variables (r ≤ |0.8|): mean diurnal range (bio2), isothermality (bio3), temperature Seasonality (bio4), mean temperature of the wettest quarter (bio8), mean temperature of warmest quarter (bio10), mean temperature of coldest quarter (bio11), precipitation seasonality (bio15), precipitation of wettest quarter (bio16), and precipitation of driest quarter (bio17). Replicate runs (10) of MaxEnt using the “bootstrap” method were performed to ensure reliable results. Model performance was assessed using the area under the curve (AUC) of the receiver operating characteristic plot, with 25% of the localities randomly selected to test the model. Graphics for each predicted species distribution model were drawn using S-DIVA.

Data Availability

The datasets generated and analysed during the current study are available in GenBank (accession numbers: OP785779-OP786045; OP786046-OP786312; OP786313-OP786579; OP786580 - OP786846).

Abbreviations

cpDNA:

chloroplast DNA

H:

the number of haplotypes

H d :

haplotype diversity

π :

nucleotide diversity

h S :

the average within-population gene diversity

h T :

total gene diversity

G ST :

the level of population differentiation at the species level

V T :

the geographical total haplotype diversity

V S :

geographical average haplotype diversity

N ST :

an estimate of population subdivisions for phylogenetically ordered alleles

SSD:

the sum of squared derivations

S-DIVA:

the statistical dispersal-vicariance analysis

CCSM4:

community climate system model version 4

LIG:

last inter-glacial

LGM:

last glacial maximum

MID:

mid Holocene

GBIF:

global biodiversity information facility

AUC:

the area under the curve

N m :

gene flow

AMOVA:

analyses of molecular variance

RASP:

reconstruct ancestral state in phylogenies

GRH:

glacial refugium hypothesis

F ST :

Genetic differentiation among populations

F SC :

genetic differentiation among population within groups

F CT :

Genetic differentiation between groups.

References

  1. Schaal BA, Hayworth DA, Oseni KM, Rauscher JT, Smith WA. Phylogeographic studies in plants: problems and prospects. Mol Ecol. 1998;7:465–74.

    Article  Google Scholar 

  2. Avise JC, Phylogeography. The history and formation of species. Cambridge: Harvard University Press; 2000.

    Google Scholar 

  3. Alvarez I, Wendel JF. Ribosomal its sequences and plant phylogenetic inference. Mol Phylogenet Evol. 2003;29:417–34.

    Article  CAS  PubMed  Google Scholar 

  4. Kuroda Y, Kaga A, Tomooka N, Vaughan DA. Population Genetic structure of japanese wild soybean (Glycine Soja) based on microsatellite variation. Mol Ecol. 2006;15:959–74.

    Article  CAS  PubMed  Google Scholar 

  5. Hu Y, Wang X, Zhang X, Zhou W, Chen X, Hu X. Advancing phylogeography with chloroplast DNA markers. Biodivers Sci. 2019;27:219–34.

    Article  Google Scholar 

  6. Pharmacopoeia of the People’s Republic of China. Beijing, China:Press of Chinese Medical Science and Technology. 2020.

  7. Liu X, Lin YH, Xie CX, Zeng FL, MA XC, Sun W, Tu PF, Chen SL. Ecogenetic and differentiation of genuine Medicinal materials: Ophiopogonis Radix in Sichuan and Zhejiang Province. Chin J Experimental Traditional Med Formulae. 2017;23:27–33.

    Google Scholar 

  8. Huang YJ, Chen JY, Hai-Lan SU, Huang YZ, Wan XF. Rdna-its of Radix Ophiopogonis and Radix Liriopes from different regions. Fujian J Agricultural Sci. 2009;24:508–12.

    Google Scholar 

  9. Li X, Wang Y, Sun P, Liao D. Determination of Saponin Content in Hang Maidong and Chuan Maidong Via HPLC-ELSD Analysis. Journal of analytical methods in chemistry. 2016; 2016: 7214607.

  10. Ge YH, Chen XJ, Godevac D, Bueno PCP, Abarca LFS, Jang YP, Wang M, Choi YH. Metabolic profiling of Saponin-Rich Ophiopogon Japonicus roots based on 1H NMR and HPTLC platforms 1. Planta Med. 2019;85:917–24.

    Article  CAS  PubMed  Google Scholar 

  11. Tan MX, Chen JL, Wang CC, Zou LS, Chen SY, Shi JJ, Mei YQ, Wei LF, Liu XH. Quality evaluation of Ophiopogonis Radix from two different producing Areas. Molecules. 2019;24:3220.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Lin Y, Zhu D, Qi J, Qin M, Yu B. Characterization of Homoisoflavonoids in different cultivation regions of Ophiopogon Japonicus and related antioxidant activity. J Pharm Biomed Anal. 2010;52:757–62.

    Article  PubMed  Google Scholar 

  13. Lu XY, Tong W, Wang SF, Li JH, Zheng J, Fan XH, Liu L. Comparison of the Chemical Consituents and Immunomodulatory Activity of Ophiopogonis Radix from two different producing Areas. J Pharm Biomed Anal. 2017;134:60–70.

    Article  CAS  PubMed  Google Scholar 

  14. Zhao M, Xu WF, Shen HY, Shen PQ, Zhang J, Wang DD, Xu H, Wang H, Yan TT, Wang L. Comparison of Bioactive Components and pharmacological activities of Ophiopogon Japonicas extracts from different Geographical Origins. J Pharm Biomed Anal. 2017;138:134–41.

    Article  CAS  PubMed  Google Scholar 

  15. Cen XX, Sun J, Shen XX, An WZ. Study on origin and genetic diversity of cultivated of Ophiopogon Japonicus based on srap and issr markers. J Chin Med Mater. 2021;44:555–61.

    Google Scholar 

  16. Liu YY, Lu JJ, Wang HZ, Wang ZA, Chen JG, Min H. Evaluation of genetic diversity of germplasm from Ophiopogon Japonicus planted in Zhejiang. J Zhejiang Agricultural Sci. 2017;58:2146–9.

    Google Scholar 

  17. Fawcett T. An introduction to Roc Analysis. Pattern Recognit Lett. 2005;27:861–74.

    Article  Google Scholar 

  18. Hyten D, Song QJ, Zhu YL, Choi I, Nelson R, Costa J, Specht J, Shoemaker R, Cregan P. Impacts of genetic bottlenecks on soybean genome diversity. Proc Natl Acad Sci U S A. 2006;103:16666–71.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Yamasaki M, Wright S, McMullen M. Genomic screening for Artificial Selection during Domestication and Improvement in Maize. Ann Botany. 2007;100:967–73.

    Article  Google Scholar 

  20. Kovach M, McCouch S. Leveraging natural diversity: back through the Bottleneck. Curr Opin Plant Biol. 2008;11:193–200.

    Article  CAS  PubMed  Google Scholar 

  21. Chen C, Li P, Wang RH, Schaal BA, Fu CX, Scrophulariaceae. PLoS ONE. 2014;9:e105064.

    Article  PubMed  PubMed Central  Google Scholar 

  22. Huang R, Liu Y, Chen J, Lu Z, Wang J, He W, Chao Z, Tian E. Limited genetic diversity and high differentiation in Angelica Dahurica resulted from Domestication: insights to breeding and conservation. BMC Plant Biol. 2022;22:141.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Zhang YH, Yu QS, Zhang Q, Hu XK, Hu J, Fan BL. Regional-Scale differentiation and phylogeography of a Desert Plant Allium Mongolicum (Liliaceae) inferred from Chloroplast DNA sequence variation. Plant Syst Evol. 2017;303:451–66.

    Article  Google Scholar 

  24. Sun JH, Wang YH, Garran TA, Qiao P, Wang ML, Yuan QJ, Guo LP, Huang LQ. Heterogeneous genetic diversity estimation of a Promising Domestication Medicinal Motherwort Leonurus Cardiaca based on Chloroplast Genome Resources. Front Genet. 2021;12:721022.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Yu Y, Wang L, Sun JH, Zhong WH, Zhang T, Guo LP, Yuan QJ. Genetic diversity and genetic structure evaluation of cultivated chinese wolfberry (Lycium Barbarum) based on microsatellite Population Genetics. Zhongguo Zhong Yao Za Zhi. 2020;45:838–45.

    PubMed  Google Scholar 

  26. Guo QS, Wang CL. Retrospect and Prospect of Medicinal plants cultivation in China. China J Chin Materia Med. 2015;40:3391–4.

    Google Scholar 

  27. Miller A, Gross B. From forest to field: perennial fruit crop domestication. Am J Bot. 2011;98:1389–414.

    Article  PubMed  Google Scholar 

  28. Miller A, Schaal B. Domestication and the distribution of genetic variation in Wild and cultivated populations of the Mesoamerican Fruit Tree Spondias Purpurea L. (Anacardiaceae). Mol Ecol. 2006;15:1467–80.

    Article  CAS  PubMed  Google Scholar 

  29. Slatkin M. Gene Flow and the Geographic structure of natural populations. Princeton: Princeton University Press; 1987.

    Book  Google Scholar 

  30. Wang H, Li ZF, Chen J, Zeng FL, Xie CX. Suitability evaluation and ecological characteristics of traditional producing Areas of Zhejiang Ophiopogon Japonicas. J Henan Agricultural Sci. 2016;45:89–95.

    Google Scholar 

  31. Liu J, Liu S, Chen XF, Zhang SP, Zou YF. Comprehensive comparison between Erective and Creepy Ophiopogon Japonicus of Sichuan. China J Chin Materia Med. 2009;34:2449–53.

    Google Scholar 

  32. Wright S. Isolation by Distance. Genetics. 1943;28:114–38.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Templeton A, Routman E. Separating Population structure from Population History: a cladistic analysis of the geographical distribution of mitochondrial DNA haplotypes in the Tiger Salamander, Ambystoma Tigrinum. Genetics. 1995;140:767–82.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Frankel OH. The conservation of Plant Biodiversity. Cambridge: Cambridge University Press; 1995.

    Google Scholar 

  35. Zhao JC, Wang YH, Weng QQ, Jin Y, Zhang W. Herbal Textual Research on ″Ophiopogonis Radix″ in chinese classical prescriptions. Mod Chin Med. 2020;22:1381–92.

    Google Scholar 

  36. Kassa M, Penmetsa R, Carrasquilla-Garcia N, Sarma B, Datta S, Upadhyaya H, Varshney R, von Wettberg E, Cook D. Genetic patterns of domestication in Pigeonpea (Cajanus Cajan (L.) Millsp.) And Wild Cajanus relatives. PLoS ONE. 2012;7:e39563.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  37. Song MF, Guan YH, Zhang Y, Li HT, Zhang LX, Zhang ZL. Genetic Diversity Assessment of a chinese Medicinal Endemic Species, Aspidopterys Obcordata Var. Obcordata, by combined molecular marker methods (ISSR & SRAP). Biochem Genet. 2021;59:283–99.

    Article  CAS  PubMed  Google Scholar 

  38. Sun YQ, Yang H, Zhang QY, Qin LP, Li P, Lee JK, Chen SC, Rahman K, Kang TG, Jia M. Genetic diversity and its conservation implications of Vitex Rotundifolia (Lamiaceae) populations in East Asia. PeerJ. 2019;7:e6194.

    Article  PubMed  PubMed Central  Google Scholar 

  39. Tzedakis PC. Buffered Tree Population Changes in a Quaternary Refugium: evolutionary implications. Science. 2003;299:825.

    Article  Google Scholar 

  40. Sommer RS, Zachos FE. Fossil evidence and phylogeography of Temperate Species: ‘glacial Refugia’ and Post-Glacial recolonization. J Biogeogr. 2010;36:2013–20.

    Article  Google Scholar 

  41. Chung MY, Vu SH, López-Pujol J, Herrando-Moraira S, Son S, Suh GU, Le HTQ, Chung MG. Comparison of genetic variation between Northern and Southern populations of Lilium Cernuum (Liliaceae): implications for Pleistocene Refugia. PLoS ONE. 2018;13:e0190520.

    Article  PubMed  PubMed Central  Google Scholar 

  42. Drummond AJ, Ashton B, Buxton S, Cheung M, Cooper A, Duran C, Field M, Heled J, Kearse M, Markowitz S, Moir R, Stones-Havas S, Sturrock S, Thierer TWA. Geneious V4.8.5. 2017. Available from http://www.geneious.com. Accessed 2022-6-6.

  43. Ronquist F, Teslenko M, van der Mark P, Ayres D, Darling A, Höhna S, Larget B, Liu L, Suchard M, Huelsenbeck J. Mrbayes 3.2: efficient bayesian phylogenetic inference and model choice across a large Model Space. Syst Biol. 2012;61:539–42.

    Article  PubMed  PubMed Central  Google Scholar 

  44. Posada D, Crandall KA, Modeltest. Testing the model of DNA substitution. Bioinformatics. 1998;14:817–18.

    Article  CAS  PubMed  Google Scholar 

  45. Clement M, Posada D, Crandall KA. TCS: a computer program to Estimate Gene Genealogies. Mol Ecol. 2000;9:1657–59.

    Article  CAS  PubMed  Google Scholar 

  46. Librado P, Rozas J. Dnasp V5: a Software for Comprehensive Analysis of DNA Polymorphism Data. Bioinformatics. 2009;25:1451–52.

    Article  CAS  PubMed  Google Scholar 

  47. Pons O, Petit RJ. Measwring and Testing Genetic differentiation with ordered Versus unordered alleles. Genet Breed. 1996;144:1237–45.

    CAS  Google Scholar 

  48. Peakall R, Smouse P. Genalex 6.5: genetic analysis in Excel. Population Genetic Software for Teaching and Research–an update. Bioinf (Oxford England). 2012;28:2537–9.

    CAS  Google Scholar 

  49. Ersts P. Geographic Distance Matrix Generator (Version 1.2.3). 2012. Available from http://biodiversityinformatics.amnh.org/open_source/gdmg. Accessed 2022-6-19.

  50. Tamura K, Stecher G, Peterson D, Filipski A, Kumar S. Mega6: Molecular Evolutionary Genetics Analysis Version 6.0. Mol Biol Evol. 2013;30:2725–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  51. Excoffier L, Lischer HE. Arlequin Suite Ver 3.5: a New Series of Programs to perform Population Genetics analyses under Linux and Windows. Mol Ecol Resour. 2010;10:564–7.

    Article  PubMed  Google Scholar 

  52. Yu Y, Harris AJ, Blair C, He X. Rasp (reconstruct ancestral state in Phylogenies): a Tool for historical Biogeography. Mol Phylogenet Evol. 2015;87:46–9.

    Article  PubMed  Google Scholar 

Download references

Acknowledgements

I am grateful to related local institutions and staff in Sichuan and Zhejiang for helping collect the experimental materials. I am thankful to Kaohua Liu and Xiaoqing Jin for their assistance in the collection of the samples.

Funding

This work was supported by the Research Project of Zhejiang Chinese Medical University [grant number: 2021JKJNTZ007B].

Author information

Author notes

  1. Luying Zhao and Yuling Liu contributed equally to this work.

Authors and Affiliations

  1. College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China

    Lu-ying Zhao, Yu-ling Liu, Yi Shen, Qiao-yan Zhang, Sha Liu, Qiu-ru Ren, Lu-ping Qin & Yi-qi Sun

Authors
  1. Lu-ying Zhao
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yu-ling Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yi Shen
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Qiao-yan Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Sha Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Qiu-ru Ren
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Lu-ping Qin
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Yi-qi Sun
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

Lu-ying Zhao, Qiao-yan Zhang and Yi-qi Sun designed the research; Lu-ying Zhao and Sha Liu collected the samples; Lu-ying Zhao, Yu-ling Liu, Yi Shen and Qiu-ru Ren performed the experiment, analysis and wrote the manuscript; all authors revised the manuscript. The author(s) read and approved the final manuscript.

Corresponding authors

Correspondence to Lu-ping Qin or Yi-qi Sun.

Ethics declarations

Ethics approval and consent to participate

Luping Qin undertook the formal identification of the plant material used in our study. The authors have promised that relevant permission to collect the plant used was obtained from all the owners of the private land during the collection of the plants. All local, national or international guidelines and legislation were adhered to in the production of this study.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary Material 1

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zhao, Ly., Liu, Yl., Shen, Y. et al. Phylogeography of cultivated and wild ophiopogon japonicus based on chloroplast DNA: exploration of the origin and sustainable cultivation. BMC Plant Biol 23, 242 (2023). https://doi.org/10.1186/s12870-023-04247-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12870-023-04247-2

Keywords

BMC Plant Biology

ISSN: 1471-2229

Contact us