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Liao Z, Zhu L, Liu L, Kreuzwieser J, Werner C, Du B. Comparison of Growth and Metabolomic Profiles of Two Afforestation Cypress Species Cupressus chengiana and Platycladus orientalis Grown at Minjiang Valley in Southwest China. Metabolites 2024; 14:453. [PMID: 39195549 DOI: 10.3390/metabo14080453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2024] [Revised: 08/14/2024] [Accepted: 08/15/2024] [Indexed: 08/29/2024] Open
Abstract
In recent years, afforestation has been conducted in China's hot and dry valleys. However, there is still a paucity of knowledge regarding the performance of tree species in these semi-arid regions, particularly with regard to interspecies differences. The present study compares the growth and metabolome characteristics of two widely used cypress species, namely Cupressus chengiana and Platycladus orientalis, grown at two sites with distinct climate conditions in the hot and dry Minjiang Valley in southwestern China. The findings indicate that C. chengiana trees exhibit superior growth rates compared to P. orientalis trees at both study sites. In comparison to P. orientalis trees, C. chengiana trees demonstrated a greater tendency to close their stomata in order to prevent water loss at the hotter and drier site, Llianghekou (LHK). Additionally, C. chengiana trees exhibited significantly lower hydrogen peroxide levels than P. orientalis trees, either due to lower production and/or higher scavenging of reactive oxygen species. C. chengiana trees accumulated soluble sugars as well as sugar derivatives, particularly those involved in sucrose and galactose metabolisms under stressful conditions. The species-specific differences were also reflected in metabolites involved in the tricarboxylic acid cycle, nitrogen, and secondary metabolisms. The metabolome profiles of the two species appeared to be influenced by the prevailing climatic conditions. It appeared that the trees at the drier and hotter site, LHK, were capable of efficient nitrogen uptake from the soil despite the low soil nitrogen concentration. This study is the first to compare the growth performance and metabolic profiles of two widely used tree species with high resistance to adverse conditions. In addition to the species-specific differences and adaptations to different sites, the present study also provides insights into potential management strategies to alleviate abiotic stress, particularly with regard to nitrogen nutrients, in the context of climate change.
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Affiliation(s)
- Zhengqiao Liao
- College of Life Science and Biotechnology, Mianyang Normal University, Mianxing Road West 166, Mianyang 621000, China
- Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianxing Road West 166, Mianyang 621000, China
| | - Lijun Zhu
- College of Life Science and Biotechnology, Mianyang Normal University, Mianxing Road West 166, Mianyang 621000, China
| | - Lei Liu
- College of Life Science and Biotechnology, Mianyang Normal University, Mianxing Road West 166, Mianyang 621000, China
- Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianxing Road West 166, Mianyang 621000, China
| | - Jürgen Kreuzwieser
- Chair of Ecosystem Physiology, Institute of Forest Sciences, University of Freiburg, Georges-Köhler-Allee 53, D-79110 Freiburg, Germany
| | - Christiane Werner
- Chair of Ecosystem Physiology, Institute of Forest Sciences, University of Freiburg, Georges-Köhler-Allee 53, D-79110 Freiburg, Germany
| | - Baoguo Du
- College of Life Science and Biotechnology, Mianyang Normal University, Mianxing Road West 166, Mianyang 621000, China
- Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianxing Road West 166, Mianyang 621000, China
- Chair of Ecosystem Physiology, Institute of Forest Sciences, University of Freiburg, Georges-Köhler-Allee 53, D-79110 Freiburg, Germany
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Xu WQ, Ren CQ, Zhang XY, Comes HP, Liu XH, Li YG, Kettle CJ, Jalonen R, Gaisberger H, Ma YZ, Qiu YX. Genome sequences and population genomics reveal climatic adaptation and genomic divergence between two closely related sweetgum species. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:1372-1387. [PMID: 38343032 DOI: 10.1111/tpj.16675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 01/24/2024] [Accepted: 01/29/2024] [Indexed: 05/31/2024]
Abstract
Understanding the genetic basis of population divergence and adaptation is an important goal in population genetics and evolutionary biology. However, the relative roles of demographic history, gene flow, and/or selective regime in driving genomic divergence, climatic adaptation, and speciation in non-model tree species are not yet fully understood. To address this issue, we generated whole-genome resequencing data of Liquidambar formosana and L. acalycina, which are broadly sympatric but altitudinally segregated in the Tertiary relict forests of subtropical China. We integrated genomic and environmental data to investigate the demographic history, genomic divergence, and climatic adaptation of these two sister species. We inferred a scenario of allopatric species divergence during the late Miocene, followed by secondary contact during the Holocene. We identified multiple genomic islands of elevated divergence that mainly evolved through divergence hitchhiking and recombination rate variation, likely fostered by long-term refugial isolation and recent differential introgression in low-recombination genomic regions. We also found some candidate genes with divergent selection signatures potentially involved in climatic adaptation and reproductive isolation. Our results contribute to a better understanding of how late Tertiary/Quaternary climatic change influenced speciation, genomic divergence, climatic adaptation, and introgressive hybridization in East Asia's Tertiary relict flora. In addition, they should facilitate future evolutionary, conservation genomics, and molecular breeding studies in Liquidambar, a genus of important medicinal and ornamental values.
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Affiliation(s)
- Wu-Qin Xu
- Systematic & Evolutionary Botany and Biodiversity Group, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- Zhejiang Lab, Hangzhou, Zhejiang, China
| | - Chao-Qian Ren
- Systematic & Evolutionary Botany and Biodiversity Group, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
| | - Xin-Yi Zhang
- Systematic & Evolutionary Botany and Biodiversity Group, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
| | - Hans-Peter Comes
- Department of Environment & Biodiversity, Salzburg University, Salzburg, Austria
| | - Xin-Hong Liu
- Zhejiang Academy of Forestry, Hangzhou, 310023, China
| | - Yin-Gang Li
- Zhejiang Academy of Forestry, Hangzhou, 310023, China
| | | | - Riina Jalonen
- Bioversity International, Regional Office for Asia, Penang, Malaysia
| | | | - Ya-Zhen Ma
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
| | - Ying-Xiong Qiu
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
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Kou Y, Fan D, Cheng S, Yang Y, Wang M, Wang Y, Zhang Z. Peripatric speciation within Torreya fargesii (Taxaceae) in the Hengduan Mountains inferred from multi-loci phylogeography. BMC Ecol Evol 2023; 23:74. [PMID: 38087226 PMCID: PMC10714551 DOI: 10.1186/s12862-023-02183-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 11/28/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND The Hengduan Mountains (HDM) are one of the major global biodiversity hotspots in the world. Several evolutionary scenarios, especially in-situ diversification, have been proposed to account for the high species richness of temperate plants. However, peripatric speciation, an important mode of allopatric speciation, has seldom been reported in this region. RESULTS Here, two chloroplast DNA regions and 14 nuclear loci were sequenced for 112 individuals from 10 populations of Torreya fargesii var. fargesii and 63 individuals from 6 populations of T. fargesii var. yunnanensis. Population genetic analyses revealed that the two varieties are well differentiated genetically (FST, 0.5765) and have uneven genetic diversity (π, 0.00221 vs. 0.00073 on an average of nuclear loci). The gene genealogical relationship showed that T. fargesii var. yunnanensis is inferred as derived from T. fargesii var. fargesii, which was further supported by the coalescent simulations (DIYABC, fastsimcoal2 and IMa2). By the coalescent simulations, the divergence time (~ 2.50-3.65 Ma) and the weak gene flow between the two varieties were detected. The gene flow was asymmetrical and only occurred in later stages of divergence, which is caused by second contact due to the population expansion (~ 0.61 Ma) in T. fargesii var. fargesii. In addition, niche modeling indicated that the two varieties are differentiated geographically and ecologically and have unbalanced distribution range. CONCLUSIONS Overall, T. fargesii var. fargesii is always parapatric with respect to T. fargesii var. yunnanensis, and the latter derived from the former in peripatry of the HDM following a colonization from central China during the late Pliocene. Our findings demonstrate that peripatric speciation following dispersal events may be an important evolutionary scenario for the formation of biodiversity hotspot of the HDM.
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Affiliation(s)
- Yixuan Kou
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Guilin, China
- Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin, Guangxi Normal University, Guilin, China
- Laboratory of Subtropical Biodiversity, Jiangxi Agricultural University, Nanchang, China
| | - Dengmei Fan
- Laboratory of Subtropical Biodiversity, Jiangxi Agricultural University, Nanchang, China
| | - Shanmei Cheng
- Laboratory of Subtropical Biodiversity, Jiangxi Agricultural University, Nanchang, China
| | - Yi Yang
- Laboratory of Subtropical Biodiversity, Jiangxi Agricultural University, Nanchang, China
| | - Meixia Wang
- Laboratory of Subtropical Biodiversity, Jiangxi Agricultural University, Nanchang, China
| | - Yujin Wang
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China.
| | - Zhiyong Zhang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Guilin, China.
- Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin, Guangxi Normal University, Guilin, China.
- Laboratory of Subtropical Biodiversity, Jiangxi Agricultural University, Nanchang, China.
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Hu H, Wang Q, Hao G, Zhou R, Luo D, Cao K, Yan Z, Wang X. Insights into the phylogenetic relationships and species boundaries of the Myricaria squamosa complex (Tamaricaceae) based on the complete chloroplast genome. PeerJ 2023; 11:e16642. [PMID: 38099308 PMCID: PMC10720482 DOI: 10.7717/peerj.16642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 11/19/2023] [Indexed: 12/17/2023] Open
Abstract
Myricaria plants are widely distributed in Eurasia and are helpful for windbreak and embankment protection. Current molecular evidence has led to controversy regarding species boundaries within the Myricaria genus and interspecific phylogenetic relationships between three specific species-M. bracteata, M. paniculata and M. squamosa-which have remained unresolved. This study treated these three unresolved taxa as a species complex, named the M. squamosa complex. The genome skimming approach was used to determine 35 complete plastome sequences and nuclear ribosomal DNA sequences for the said complex and other closely related species, followed by de novo assembly. Comparative analyses were conducted across Myricaria to identify the genome size, gene content, repeat type and number, SSR (simple sequence repeat) abundance, and codon usage bias of chloroplast genomes. Tree-based species delimitation results indicated that M. bracteata, M. paniculata and M. squamosa could not be distinguished and formed two monophyletic lineages (P1 and P2) that were clustered together. Compared to plastome-based species delimitation, the standard nuclear DNA barcode had the lowest species resolution, and the standard chloroplast DNA barcode and group-specific barcodes delimitated a maximum of four out of the five species. Plastid phylogenomics analyses indicated that the monophyletic M. squamosa complex is comprised of two evolutionarily significant units: one in the western Tarim Basin and the other in the eastern Qinghai-Tibet Plateau. This finding contradicts previous species discrimination and promotes the urgent need for taxonomic revision of the threatened genus Myricaria. Dense sampling and plastid genomes will be essential in this effort. The super-barcodes and specific barcode candidates outlined in this study will aid in further studies of evolutionary history.
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Affiliation(s)
- Huan Hu
- Microbial Resources and Drug Development Key Laboratory of Guizhou Tertiary Institution, Zunyi Medical University, Zunyi, China
| | - Qian Wang
- Microbial Resources and Drug Development Key Laboratory of Guizhou Tertiary Institution, Zunyi Medical University, Zunyi, China
| | - Guoqian Hao
- School of Life Science and Food Engineering, Yibin University, Yibin, China
| | - Ruitao Zhou
- School of Preclinical Medicine, Zunyi Medical University, Zunyi, China
| | - Dousheng Luo
- School of Preclinical Medicine, Zunyi Medical University, Zunyi, China
| | - Kejun Cao
- School of Preclinical Medicine, Zunyi Medical University, Zunyi, China
| | - Zhimeng Yan
- School of Medical Information Engineering, Zunyi Medical University, Zunyi, China
| | - Xinyu Wang
- Key Laboratory of Medical Electrophysiology, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
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Qin HT, Mӧller M, Milne R, Luo YH, Zhu GF, Li DZ, Liu J, Gao LM. Multiple paternally inherited chloroplast capture events associated with Taxus speciation in the Hengduan Mountains. Mol Phylogenet Evol 2023; 189:107915. [PMID: 37666379 DOI: 10.1016/j.ympev.2023.107915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 06/16/2023] [Accepted: 09/01/2023] [Indexed: 09/06/2023]
Abstract
Mountainous regions provide a multitude of habitats and opportunities for complex speciation scenarios. Hybridization leading to chloroplast capture, which can be revealed by incongruent phylogenetic trees, is one possible outcome. Four allopatric Taxus lineages (three species and an undescribed lineage) from the Hengduan Mountains, southwest China, exhibit conflicting phylogenetic relationships between nuclear and chloroplast phylogenies. Here, we use multi-omic data at the population level to investigate their historical speciation processes. Population genomic analysis based on ddRAD-seq data revealed limited contemporary inter-specific gene flow involving only populations located close to another species. In a historical context, chloroplast and nuclear data (transcriptome) consistently showed conflicting phylogenetic relationships for T. florinii and the Emei type lineage. ILS and chloroplast recombination were excluded as possible causes, and transcriptome and ddRAD-seq data revealed an absence of the mosaic nuclear genomes that characterize hybrid origin scenarios. Therefore, T. florinii appears to have originated when a lineage of T. florinii captured the T. chinensis plastid type, whereas plastid introgression in the opposite direction generated the Emei Type. All four species have distinct ecological niche based on community investigations and ecological niche analyses. We propose that the origins of both species represent very rare examples of chloroplast capture events despite the paternal cpDNA inheritance of gymnosperms. Specifically, allopatrically and/or ecologically diverged parental species experienced a rare secondary contact, subsequent hybridization and reciprocal chloroplast capture, generating two new lineages, each of which acquired a unique ecological niche. These events might have been triggered by orogenic activities of the Hengduan Mountains and an intensification of the Asian monsoon in the late Miocene, and may represent a scenario more common in these mountains than presently known.
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Affiliation(s)
- Han-Tao Qin
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Michael Mӧller
- Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, United Kingdom
| | - Richard Milne
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JH, United Kingdom
| | - Ya-Huang Luo
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; Lijiang Forest Biodiversity National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang 674100, Yunnan, China
| | - Guang-Fu Zhu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - De-Zhu Li
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; University of Chinese Academy of Sciences, Beijing 100049, China; Lijiang Forest Biodiversity National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang 674100, Yunnan, China.
| | - Jie Liu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China.
| | - Lian-Ming Gao
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China; Lijiang Forest Biodiversity National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang 674100, Yunnan, China.
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Zhao YJ, Yin GS, Gong X. RAD-sequencing improves the genetic characterization of a threatened tree peony ( Paeonia ludlowii) endemic to China: Implications for conservation. PLANT DIVERSITY 2023; 45:513-522. [PMID: 37936813 PMCID: PMC10625974 DOI: 10.1016/j.pld.2022.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 06/06/2022] [Accepted: 07/12/2022] [Indexed: 11/09/2023]
Abstract
Compared with traditional genetic markers, genomic approaches have proved valuable to the conservation of endangered species. Paeonia ludlowii having rarely and pure yellow flowers, is one of the world's most famous tree peonies. However, only several wild populations remain in the Yarlung Zangbo Valley (Nyingchi and Shannan regions, Xizang) in China due to increasing anthropogenic impact on the natural habitats. We used genome-wide single nucleotide polymorphisms to elucidate the spatial pattern of genetic variation, population structure and demographic history of P. ludlowii from the fragmented region comprising the entire range of this species, aiming to provide a basis for conserving the genetic resources of this species. Unlike genetic uniformity among populations revealed in previous studies, we found low but varied levels of intra-population genetic diversity, in which lower genetic diversity was detected in the population in Shannan region compared to those in Nyingzhi region. These spatial patterns may be likely associated with different population sizes caused by micro-environment differences in these two regions. Additionally, low genetic differentiation among populations (Fst = 0.0037) were detected at the species level. This line of evidence, combined with the result of significant genetic differentiation between the two closest populations and lack of isolation by distance, suggested that shared ancestry among now remnant populations rather than contemporary genetic connectivity resulted in subtle population structure. Demographic inference suggested that P. ludlowii probably experienced a temporal history of sharp population decline during the period of Last Glacial Maximum, and a subsequent bottleneck event resulting from prehistoric human activities on the Qinghai-Tibet Plateau. All these events, together with current habitat fragment and excavation might contribute to the endangered status of P. ludlowii. Our study improved the genetic characterization of the endangered tree peony (P. ludlowii) in China, and these genetic inferences should be considered when making different in situ and ex situ conservation actions for P. ludlowii in this evolutionary hotspot region.
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Affiliation(s)
- Yu-Juan Zhao
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China
- Yunnan Key Laboratory for Wild Plant Resources, Kunming 650201, Yunnan, China
| | - Gen-Shen Yin
- Kunming University, Institute of Agriculture and Life Sciences, Kunming 650214, Yunnan, China
| | - Xun Gong
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China
- Yunnan Key Laboratory for Wild Plant Resources, Kunming 650201, Yunnan, China
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Xia C, Zuo Y, Xue T, Kang M, Zhang H, Zhang X, Wang B, Zhang J, Deng H. The genetic structure and demographic history revealed by whole-genome resequencing provide insights into conservation of critically endangered Artocarpus nanchuanensis. FRONTIERS IN PLANT SCIENCE 2023; 14:1224308. [PMID: 37575939 PMCID: PMC10415164 DOI: 10.3389/fpls.2023.1224308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 07/12/2023] [Indexed: 08/15/2023]
Abstract
Introduction Whole-genome resequencing technology covers almost all nucleotide variations in the genome, which makes it possible to carry out conservation genomics research on endangered species at the whole-genome level. Methods In this study, based on the whole-genome resequencing data of 101 critically endangered Artocarpus nanchuanensis individuals, we evaluated the genetic diversity and population structure, inferred the demographic history and genetic load, predicted the potential distributions in the past, present and future, and classified conservation units to propose targeted suggestions for the conservation of this critically endangered species. Results Whole-genome resequencing for A. nanchuanensis generated approximately 2 Tb of data. Based on abundant mutation sites (25,312,571 single nucleotide polymorphisms sites), we revealed that the average genetic diversity (nucleotide diversity, π) of different populations of A. nanchuanensis was relatively low compared with other trees that have been studied. And we also revealed that the NHZ and QJT populations harboured unique genetic backgrounds and were significantly separated from the other five populations. In addition, positive genetic selective signals, significantly enriched in biological processes related to terpene synthesis, were identified in the NHZ population. The analysis of demographic history of A. nanchuanensis revealed the existence of three genetic bottleneck events. Moreover, abundant genetic loads (48.56% protein-coding genes) were identified in Artocarpus nanchuanensis, especially in genes related to early development and immune function of plants. The predication analysis of suitable habitat areas indicated that the past suitable habitat areas shifted from the north to the south due to global temperature decline. However, in the future, the actual distribution area of A. nanchuanensis will still maintain high suitability. Discussion Based on total analyses, we divided the populations of A. nanchuanensis into four conservation units and proposed a number of practical management suggestions for each conservation unit. Overall, our study provides meaningful guidance for the protection of A. nanchuanensis and important insight into conservation genomics research.
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Affiliation(s)
- Changying Xia
- Center for Biodiversity Conservation and Utilization, School of Life Sciences, Southwest University, Chongqing, China
| | - Youwei Zuo
- Center for Biodiversity Conservation and Utilization, School of Life Sciences, Southwest University, Chongqing, China
| | - Tiantian Xue
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Ming Kang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Huan Zhang
- Center for Biodiversity Conservation and Utilization, School of Life Sciences, Southwest University, Chongqing, China
| | - Xiaoxia Zhang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Binru Wang
- Center for Biodiversity Conservation and Utilization, School of Life Sciences, Southwest University, Chongqing, China
| | - Jiabin Zhang
- Center for Biodiversity Conservation and Utilization, School of Life Sciences, Southwest University, Chongqing, China
| | - Hongping Deng
- Center for Biodiversity Conservation and Utilization, School of Life Sciences, Southwest University, Chongqing, China
- Low Carbon and Ecological Environment Protection Research Center, Chongqing Academy of Science and Technology, Chongqing, China
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8
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Liu G, Xue G, Zhao T, Li Y, Yue L, Song H, Liu Q. Population structure and phylogeography of three closely related tree peonies. Ecol Evol 2023; 13:e10073. [PMID: 37274151 PMCID: PMC10234759 DOI: 10.1002/ece3.10073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/23/2023] [Accepted: 04/25/2023] [Indexed: 06/06/2023] Open
Abstract
Paeonia decomposita, Paeonia rotundiloba, and Paeonia rockii are three closely related species of Sect. Moutan is distributed in the montane area of the Eastern Hengduan Mountain region. Understanding the population history of these three tree peony species could contribute to unraveling the evolutionary patterns of undergrowth species in this hotspot area. We used one nuclear DNA marker (internal transcribed spacer region, ITS) and two chloroplast DNA markers (matK, ycf1) to reconstruct the phylogeographic pattern of the populations. In total, 228 individuals from 17 populations of the three species were analyzed in this study. Three nuclear clades (Clade I - Clade III) and four maternal clades (Clade A - Clade D) were reconstructed. Molecular dating suggested that young lineages diverged during the late Pliocene and early Pleistocene, younger than the uplift of the Hengduan Mountains but older than the last glacial maximum (LGM). Significant population and phylogeographic structures were detected at both markers. Furthermore, the populations of these tree peonies were overall at equilibrium during the climatic oscillations of the Pleistocene. The simulated palaeoranges of the three species during the LGM period mostly overlapped, which could have led to cross-breeding events. We propose an evolutionary scenario in which mountain orogenesis around the Hengduan Mountain area triggered parapatric isolation between maternal lineages of tree peonies. Subsequent climatic fluctuations drove migration and range recontact of these populations along the valleys. This detailed evolutionary history provides new insights into the phylogeographic pattern of species from mountain-valley systems.
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Affiliation(s)
- Guangli Liu
- College of Landscape ArchitectureSichuan Agricultural UniversityChengduChina
| | - Ge Xue
- College of Landscape ArchitectureSichuan Agricultural UniversityChengduChina
| | - Tingting Zhao
- College of Landscape ArchitectureSichuan Agricultural UniversityChengduChina
| | - Yang Li
- College of Landscape ArchitectureSichuan Agricultural UniversityChengduChina
| | - Liangliang Yue
- National Plateau Wetlands Research Center, College of WetlandsSouthwest Forestry UniversityKunmingChina
| | - Huixing Song
- College of Landscape ArchitectureSichuan Agricultural UniversityChengduChina
| | - Qinglin Liu
- College of Landscape ArchitectureSichuan Agricultural UniversityChengduChina
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Sun QH, Morales-Briones DF, Wang HX, Landis JB, Wen J, Wang HF. Target sequence capture data shed light on the deeper evolutionary relationships of subgenus Chamaecerasus in Lonicera (Caprifoliaceae). Mol Phylogenet Evol 2023; 184:107808. [PMID: 37156329 DOI: 10.1016/j.ympev.2023.107808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 04/29/2023] [Accepted: 05/01/2023] [Indexed: 05/10/2023]
Abstract
The genus Lonicera L. is widely distributed in the north temperate zone and is well-known for its high species richness and morphological diversity. Previous studies have suggested that many sections of Lonicera are not monophyletic and phylogenetic relationships within the genus are still poorly resolved. In this study, we sampled 37 accessions of Lonicera, covering four sections of subgenus Chamaecerasus plus six outgroup taxa, to recover the main clades of Lonicera based on sequences of nuclear loci generated by target enrichment and cpDNA from genome skimming. We found extensive cytonuclear discordance across the subgenus. Both nuclear and plastid phylogenetic analyses supported subgenus Chamaecerasus sister to subgenus Lonicera. Within subgenus Chamaecerasus, sections Isika and Nintooa were each polyphyletic. Based on the nuclear and chloroplast phylogenies, we propose to merge Lonicera korolkowii into section Coeloxylosteum and Lonicera caerulea into section Nintooa. In addition, Lonicera is estimated to have originated in the mid Oligocene (26.45 Ma). The stem age of section Nintooa was estimated to be 17.09 Ma (95% HPD: 13.30-24.45). The stem age of subgenus Lonicera was estimated to be 16.35 Ma (95% HPD: 14.12-23.66). Ancestral area reconstruction analyses indicate that subgenus Chamaecerasus originated in East Asia and Central Asia. In addition, sections Coeloxylosteum and Nintooa originated in East Asia, with subsequent dispersals into other areas. The aridification of the Asian interior likely promoted the rapid radiation of sections Coeloxylosteum and Nintooa within this region. Moreover, our biogeographic analysis fully supports the Bering and the North Atlantic Land Bridge hypotheses for the intercontinental migrations in the Northern Hemisphere. Overall, this study provides new insights into the taxonomically complex lineages of subgenus Chamaecerasus and the process of speciation.
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Affiliation(s)
- Qing-Hui Sun
- Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China; School of Tropical Medicine, Hainan Medical University, Haikou, Hainan, 571199, China
| | - Diego F Morales-Briones
- Department of Plant and Microbial Biology, College of Biological Sciences, University of Minnesota, 140 Gortner Laboratory, 1479 Gortner Avenue, Saint Paul, MN 55108, USA; Systematics, Biodiversity and Evolution of Plants, Department of Biology I, Ludwig-Maximilians-Universität München, Menzinger Str. 67, 80638, Munich, Germany
| | - Hong-Xin Wang
- Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China; Zhai Mingguo Academician Work Station, Sanya University, Sanya 572022, China
| | - Jacob B Landis
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY 14850, USA; BTI Computational Biology Center, Boyce Thompson Institute, Ithaca, NY 14853, USA
| | - Jun Wen
- Department of Botany, National Museum of Natural History, MRC-166, Smithsonian Institution, PO Box 37012, Washington, DC 20013-7012, USA
| | - Hua-Feng Wang
- Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China; Key Laboratory of Tropical Biological Resources of Ministry of Education, College of Tropical Crops, Hainan University, Haikou 570228, China.
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10
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Yang Z, Ma W, Wang L, Yang X, Zhao T, Liang L, Wang G, Ma Q. Population genomics reveals demographic history and selection signatures of hazelnut ( Corylus). HORTICULTURE RESEARCH 2023; 10:uhad065. [PMID: 37249951 PMCID: PMC10208898 DOI: 10.1093/hr/uhad065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 04/02/2023] [Indexed: 05/31/2023]
Abstract
Hazelnut (Corylus spp.) is known as one of the four famous tree nuts in the world due to its pleasant taste and nutritional benefits. However, hazelnut promotion worldwide is increasingly challenged by global climate change, limiting its production to a few regions. Focusing on the eurytopic Section Phyllochlamys, we conducted whole-genome resequencing of 125 diverse accessions from five geo-ecological zones in Eurasia to elucidate the genomic basis of adaptation and improvement. Population structure inference outlined five distinct genetic lineages corresponding to climate conditions and breeding background, and highlighted the differentiation between European and Asian lineages. Demographic dynamics and ecological niche modeling revealed that Pleistocene climatic oscillations dominantly shaped the extant genetic patterns, and multiple environmental factors have contributed to the lineage divergence. Whole-genome scans identified 279, 111, and 164 selective sweeps that underlie local adaptation in Corylus heterophylla, Corylus kweichowensis, and Corylus yunnanensis, respectively. Relevant positively selected genes were mainly involved in regulating signaling pathways, growth and development, and stress resistance. The improvement signatures of hybrid hazelnut were concentrated in 312 and 316 selected genes, when compared to C. heterophylla and Corylus avellana, respectively, including those that regulate protein polymerization, photosynthesis, and response to water deprivation. Among these loci, 22 candidate genes were highly associated with the regulation of biological quality. Our study provides insights into evolutionary processes and the molecular basis of how sibling species adapt to contrasting environments, and offers valuable resources for future climate-resilient breeding.
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Affiliation(s)
- Zhen Yang
- Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Wenxu Ma
- Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
- Forest Botany and Tree Physiology, University of Goettingen, Goettingen, 37077, Germany
| | - Lujun Wang
- Research Institute of Economic Forest Cultivation and Processing, Anhui Academy of Forestry, Hefei, 230031, China
| | - Xiaohong Yang
- Research Institute of Walnut, Guizhou Academy of Forestry, Guiyang, 550005, China
| | - Tiantian Zhao
- Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Lisong Liang
- Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Guixi Wang
- Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
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11
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Yu J, Niu Y, You Y, Cox CJ, Barrett RL, Trias-Blasi A, Guo J, Wen J, Lu L, Chen Z. Integrated phylogenomic analyses unveil reticulate evolution in Parthenocissus (Vitaceae), highlighting speciation dynamics in the Himalayan-Hengduan Mountains. THE NEW PHYTOLOGIST 2023; 238:888-903. [PMID: 36305244 DOI: 10.1111/nph.18580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Hybridization caused by frequent environmental changes can lead both to species diversification (speciation) and to speciation reversal (despeciation), but the latter has rarely been demonstrated. Parthenocissus, a genus with its trifoliolate lineage in the Himalayan-Hengduan Mountains (HHM) region showing perplexing phylogenetic relationships, provides an opportunity for investigating speciation dynamics based on integrated evidence. We investigated phylogenetic discordance and reticulate evolution in Parthenocissus based on rigorous analyses of plastome and transcriptome data. We focused on reticulations in the trifoliolate lineage in the HHM region using a population-level genome resequencing dataset, incorporating evidence from morphology, distribution, and elevation. Comprehensive analyses confirmed multiple introgressions within Parthenocissus in a robust temporal-spatial framework. Around the HHM region, at least three hybridization hot spots were identified, one of which showed evidence of ongoing speciation reversal. We present a solid case study using an integrative methodological approach to investigate reticulate evolutionary history and its underlying mechanisms in plants. It demonstrates an example of speciation reversal through frequent hybridizations in the HHM region, which provides new perspectives on speciation dynamics in mountainous areas with strong topographic and environmental heterogeneity.
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Affiliation(s)
- Jinren Yu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanting Niu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- China National Botanical Garden, Beijing, 100093, China
| | - Yichen You
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Cymon J Cox
- Centro de Ciências do Mar, Universidade do Algarve, Gambelas, Faro, 8005-319, Portugal
| | - Russell L Barrett
- National Herbarium of New South Wales, Australian Botanic Garden, Locked Bag 6002, Mount Annan, 2567, NSW, Australia
| | | | - Jing Guo
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center of Genetics and Development, Ministry of Education Key Laboratory of Biodiversity and Ecological Engineering, Institute of Plant Biology, Center of Evolutionary Biology, School of Life Sciences, Fudan University, Shanghai, 200433, China
| | - Jun Wen
- Department of Botany, National Museum of Natural History, MRC-166, Smithsonian Institution, Washington, DC, 20013-7012, USA
| | - Limin Lu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Zhiduan Chen
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
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12
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Guo JF, Zhao W, Andersson B, Mao JF, Wang XR. Genomic clines across the species boundary between a hybrid pine and its progenitor in the eastern Tibetan Plateau. PLANT COMMUNICATIONS 2023:100574. [PMID: 36906801 PMCID: PMC10363505 DOI: 10.1016/j.xplc.2023.100574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 02/09/2023] [Accepted: 03/08/2023] [Indexed: 06/18/2023]
Abstract
Most species have clearly defined distribution ranges and ecological niches. The genetic and ecological causes of species differentiation and the mechanisms that maintain species boundaries between newly evolved taxa and their progenitors are, however, less clearly defined. This study investigated the genetic structure and clines in Pinus densata, a pine of hybrid origin on the southeastern Tibetan Plateau, to gain an understanding of the contemporary dynamics of species barriers. We analyzed genetic diversity in a range-wide collection of P. densata and representative populations of its progenitors, Pinus tabuliformis and Pinus yunnanensis, using exome capture sequencing. We detected four distinct genetic groups within P. densata that reflect its migration history and major gene-flow barriers across the landscape. The demographies of these genetic groups in the Pleistocene were associated with regional glaciation histories. Interestingly, population sizes rebounded rapidly during interglacial periods, suggesting persistence and resilience of the species during the Quaternary ice age. In the contact zone between P. densata and P. yunnanensis, 3.36% of the analyzed loci (57 849) showed exceptional patterns of introgression, suggesting their potential roles in either adaptive introgression or reproductive isolation. These outliers showed strong clines along critical climate gradients and enrichment in a number of biological processes relevant to high-altitude adaptation. This indicates that ecological selection played an important role in generating genomic heterogeneity and a genetic barrier across a zone of species transition. Our study highlights the forces that operate to maintain species boundaries and promote speciation in the Qinghai-Tibetan Plateau and other mountain systems.
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Affiliation(s)
- Jing-Fang Guo
- National Engineering Research Center of Tree Breeding and Ecological Restoration; State Key Laboratory of Tree Genetics and Breeding; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Wei Zhao
- Department of Ecology and Environmental Science, Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden
| | - Bea Andersson
- Department of Ecology and Environmental Science, Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden
| | - Jian-Feng Mao
- National Engineering Research Center of Tree Breeding and Ecological Restoration; State Key Laboratory of Tree Genetics and Breeding; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Xiao-Ru Wang
- Department of Ecology and Environmental Science, Umeå Plant Science Centre, Umeå University, 90187 Umeå, Sweden.
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13
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Chen C, Ruhfel BR, Li J, Wang Z, Zhang L, Zhang L, Mao X, Wang J, He D, Luo Y, Hu Q, Duan Y, Xu X, Xi Z, Liu J. Phylotranscriptomics of Swertiinae (Gentianaceae) reveals that key floral traits are not phylogenetically correlated. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023. [PMID: 36749624 DOI: 10.1111/jipb.13464] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
Establishing how lineages with similar traits are phylogenetically related remains critical for understanding the origin of biodiversity on Earth. Floral traits in plants are widely used to explore phylogenetic relationships and to delineate taxonomic groups. The subtribe Swertiinae (Gentianaceae) comprises more than 350 species with high floral diversity ranging from rotate to tubular corollas and possessing diverse nectaries. Here we performed phylogenetic analysis of 60 species from all 15 genera of the subtribe Swertiinae sensu Ho and Liu, representing the range of floral diversity, using data from the nuclear and plastid genomes. Extensive topological conflicts were present between the nuclear and plastome trees. Three of the 15 genera represented by multiple species are polyphyletic in both trees. Key floral traits including corolla type, absence or presence of lobe scales, nectary type, nectary position, and stigma type are randomly distributed in the nuclear and plastome trees without phylogenetic correlation. We also revealed the likely ancient hybrid origin of one large clade comprising 10 genera with diverse floral traits. These results highlight the complex evolutionary history of this subtribe. The phylogenies constructed here provide a basic framework for further exploring the ecological and genetic mechanisms underlying both species diversification and floral diversity.
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Affiliation(s)
- Chunlin Chen
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Brad R Ruhfel
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Jialiang Li
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Zefu Wang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Lushui Zhang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Lei Zhang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Xingxing Mao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Ji Wang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Dashan He
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Yue Luo
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Quanjun Hu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Yuanwen Duan
- Institute Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Xiaoting Xu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Zhenxiang Xi
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Jianquan Liu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education & State Key Laboratory of Hydraulics and Mountain River Engineering, College of Life Sciences, Sichuan University, Chengdu, 610065, China
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14
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Bejerman N, Dietzgen RG, Debat H. Unlocking the Hidden Genetic Diversity of Varicosaviruses, the Neglected Plant Rhabdoviruses. Pathogens 2022; 11:1127. [PMID: 36297184 PMCID: PMC9608074 DOI: 10.3390/pathogens11101127] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 09/27/2022] [Accepted: 09/27/2022] [Indexed: 09/28/2023] Open
Abstract
The genus Varicosavirus is one of six genera of plant-infecting rhabdoviruses. Varicosaviruses have non-enveloped, flexuous, rod-shaped virions and a negative-sense, single-stranded RNA genome. A distinguishing feature of varicosaviruses, which is shared with dichorhaviruses, is a bi-segmented genome. Before 2017, a sole varicosavirus was known and characterized, and then two more varicosaviruses were identified through high-throughput sequencing in 2017 and 2018. More recently, the number of known varicosaviruses has substantially increased in concert with the extensive use of high-throughput sequencing platforms and data mining approaches. The novel varicosaviruses have revealed not only sequence diversity, but also plasticity in terms of genome architecture, including a virus with a tentatively unsegmented genome. Here, we report the discovery of 45 novel varicosavirus genomes which were identified in publicly available metatranscriptomic data. The identification, assembly, and curation of the raw Sequence Read Archive reads has resulted in 39 viral genome sequences with full-length coding regions and 6 with nearly complete coding regions. The highlights of the obtained sequences include eight varicosaviruses with unsegmented genomes, which are linked to a phylogenetic clade associated with gymnosperms. These findings have resulted in the most complete phylogeny of varicosaviruses to date and shed new light on the phylogenetic relationships and evolutionary landscape of this group of plant rhabdoviruses. Thus, the extensive use of sequence data mining for virus discovery has allowed us to unlock of the hidden genetic diversity of varicosaviruses, the largely neglected plant rhabdoviruses.
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Affiliation(s)
- Nicolas Bejerman
- Instituto de Patología Vegetal, Centro de Investigaciones Agropecuarias, Instituto Nacional de Tecnología Agropecuaria (IPAVE—CIAP—INTA), Camino 60 Cuadras Km 5.5, Córdoba X5020ICA, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, Unidad de Fitopatología y Modelización Agrícola, Camino 60 Cuadras Km 5.5, Córdoba X5020ICA, Argentina
| | - Ralf G. Dietzgen
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Humberto Debat
- Instituto de Patología Vegetal, Centro de Investigaciones Agropecuarias, Instituto Nacional de Tecnología Agropecuaria (IPAVE—CIAP—INTA), Camino 60 Cuadras Km 5.5, Córdoba X5020ICA, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, Unidad de Fitopatología y Modelización Agrícola, Camino 60 Cuadras Km 5.5, Córdoba X5020ICA, Argentina
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15
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Yu XQ, Jiang YZ, Folk RA, Zhao JL, Fu CN, Fang L, Peng H, Yang JB, Yang SX. Species discrimination in Schima (Theaceae): Next-generation super-barcodes meet evolutionary complexity. Mol Ecol Resour 2022; 22:3161-3175. [PMID: 35789203 DOI: 10.1111/1755-0998.13683] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 06/20/2022] [Accepted: 06/27/2022] [Indexed: 11/26/2022]
Abstract
Plastid genome and nrDNA arrays, proposed recently as "super barcodes", might provide additional discriminatory power and overcome the limitations of traditional barcoding loci, yet super barcodes need to be tested for their effectiveness in more plant groups. Morphological homoplasy among Schima species makes the genus a model for testing the efficacy of super barcodes. In this study, we generated multiple datasets comprising standard DNA barcodes (matK, rbcL, trnH-psbA, nrITS) and super-barcodes (plastid genome, nrDNA arrays) across 58 individuals from 12 out of 13 species of Schima from China. No samples were correctly assigned to species using standard DNA barcodes and nrDNA arrays, while only 27.27% of species with multiple accessions were distinguished using the plastid genome and its partitioned datasets-the lowest estimated rate of super barcode success in the literature so far. For Schima and other taxa with similarly recently divergence and low levels of genetic variation, incomplete lineage sorting, hybridization, or taxonomic oversplitting are all possible causes of the failure. Taken together, our study suggests that by no means are super barcodes immune to the challenges imposed by evolutionary complexity. We therefore call for developing multi-locus nuclear markers for species discrimination in plant groups.
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Affiliation(s)
- Xiang-Qin Yu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences
| | - Yin-Zi Jiang
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences.,College of Life Sciences, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Ryan A Folk
- Department of Biological Sciences, Mississippi State University, 39762, MS, United States
| | - Jian-Li Zhao
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Laboratory of Ecology and Evolutionary Biology, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650500, China, China
| | - Chao-Nan Fu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences
| | - Liang Fang
- College of Life Sciences, Jiujiang University, 332000, Jiujiang, Jiangxi, China
| | - Hua Peng
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences
| | - Jun-Bo Yang
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, 650201, Kunming, Yunnan, China
| | - Shi-Xiong Yang
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences
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16
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Hou Z, Li A. Genomic Differentiation and Demographic Histories of Two Closely Related Salicaceae Species. FRONTIERS IN PLANT SCIENCE 2022; 13:911467. [PMID: 35747877 PMCID: PMC9210983 DOI: 10.3389/fpls.2022.911467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Populus alba (P. alba) and Populus davidiana (P. davidiana) are important plant species for answering a variety of issues on species evolution due to their wide distribution and ability to adapt to a variety of environments and climates. Even though P. alba and P. davidiana belong to ecologically and economically important forest trees in the Northern Hemisphere, little is known about their genomic landscape and genome divergence during speciation. We re-sequenced 20 and 19 members of P. davidiana and P. alba, respectively, and found that the Dxy value between P. alba and P. davidiana was 0.2658, whereas the F ST values were 0.2988, indicating that the genetic divergence was fairly clear. Populus davidiana and P. alba diverged from the ancestor in the middle Pleistocene, c. 0.80 Ma (95% HPD: 0.79-0.81 Ma). The population sizes of P. davidiana increased ~20,000 years ago after a considerable long-term decline following divergence. However, after differentiation, the effective population size of P. alba expanded slightly before experiencing a long-term bottleneck effect. According to the expectation of allopatric speciation, we found a significant number of genomic differentiation sites in both species' speciation events, and the majority of these genomic differentiation regions can be attributed to neutral evolutionary processes. Nevertheless, the regions with extreme divergence exist in abundance, indicating that natural selection has had an impact. Positive selection can be found in highly differentiated regions, while long-term balancing selection traits can be easily observed in low differentiated regions. According to these findings, climate differences over the Quaternary, as well as variance in linked selection and recombination, all contributed significantly to genomic divergence during allopatric speciation of the two aspens.
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17
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Yang H, Li J, Milne RI, Tao W, Wang Y, Miao J, Wang W, Ju T, Tso S, Luo J, Mao K. Genomic insights into the genotype-environment mismatch and conservation units of a Qinghai-Tibet Plateau endemic cypress under climate change. Evol Appl 2022; 15:919-933. [PMID: 35782009 PMCID: PMC9234613 DOI: 10.1111/eva.13377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 03/14/2022] [Accepted: 03/23/2022] [Indexed: 11/29/2022] Open
Abstract
Habitat loss induced by climate warming is a major threat to biodiversity, particularly to threatened species. Understanding the genetic diversity and distributional responses to climate change of threatened species is critical to facilitate their conservation and management. Cupressus gigantea, a rare conifer found in the eastern Qinghai-Tibet Plateau (QTP) at 3000-3600 m.a.s.l., is famous for its largest specimen, the King Cypress, which is >55 m tall. Here, we obtained transcriptome data from 96 samples of 10 populations covering its whole distribution and used these data to characterize genetic diversity, identify conservation units, and elucidate genomic vulnerability to future climate change. After filtering, we identified 145,336, 26,103, and 2833 single nucleotide polymorphisms in the whole, putatively neutral, and putatively adaptive datasets, respectively. Based on the whole and putatively neutral datasets, we found that populations from the Yalu Tsangpo River (YTR) and Nyang River (NR) catchments could be defined as separate management units (MUs), due to distinct genetic clusters and demographic histories. Results of gradient forest models suggest that all populations of C. gigantea may be at risk due to the high expected rate of climate change, and the NR MU had a higher risk than the YTR MU. This study deepens our understanding of the complex evolutionary history and population structure of threatened tree species in extreme environments, such as dry river valleys above 3000 m.a.s.l. in the QTP, and provides insights into their susceptibility to global climate change and potential for adaptive responses.
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Affiliation(s)
- Heng Yang
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
| | - Jialiang Li
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
| | - Richard Ian Milne
- Institute of Molecular Plant SciencesThe University of EdinburghEdinburghUK
| | - Wenjing Tao
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
| | - Yi Wang
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
| | - Jibin Miao
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
| | - Wentao Wang
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
| | - Tsam Ju
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
- College of ScienceTibet UniversityLhasaChina
| | - Sonam Tso
- College of ScienceTibet UniversityLhasaChina
| | - Jian Luo
- Tibet Key Laboratory of Forest Ecology in Plateau Area of Ministry of EducationResearch Institute of Tibet Plateau EcologyNational Key Station of Field Scientific Observation & Experiment of Alpine Forest Ecology System in NyingchiTibet Agriculture & Animal Husbandry UniversityNyingchiChina
| | - Kangshan Mao
- Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of EducationCollege of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduChina
- College of ScienceTibet UniversityLhasaChina
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18
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Wu Z, Wang Z, Xie D, Zhang J, Cai P, Li X, Xu X, Li T, Zhao J. Extensive Sympatry and Frequent Hybridization of Ecologically Divergent Aquatic Plants on the Qinghai-Tibetan Plateau. FRONTIERS IN PLANT SCIENCE 2022; 13:851151. [PMID: 35646042 PMCID: PMC9135455 DOI: 10.3389/fpls.2022.851151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 04/13/2022] [Indexed: 06/15/2023]
Abstract
Hybridization has fascinated biologists in recent centuries for its evolutionary importance, especially in plants. Hybrid zones are commonly located in regions across environmental gradients due to more opportunities to contact and ecological heterogeneity. For aquatic taxa, intrazonal character makes broad overlapping regions in intermediate environments between related species. However, we have limited information on the hybridization pattern of aquatic taxa in alpines, especially submerged macrophytes. In this study, we aimed to test the hypotheses that niche overlap and hybridization might be extensive in related aquatic plants across an altitudinal gradient. We evaluated the niche overlap in three related species pairs on the Qinghai-Tibetan Plateau and assessed the spatial pattern of hybrid populations. Obvious niche overlap and common hybridization were revealed in all three pairs of related aquatic plants. The plateau edge and river basins were broad areas for the sympatry of divergent taxa, where a large proportion of hybrid populations occurred. Hybrids are also discretely distributed in diverse habitats on the plateau. Differences in the extent of niche overlap, genetic incompatibility and phylogeographic history might lead to variation differences in hybridization patterns among the three species pairs. Our results suggested that plateau areas are a hotspot for ecologically divergent aquatic species to contact and mate and implied that hybridization may be important for the freshwater biodiversity of highlands.
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Affiliation(s)
- Zhigang Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Zhong Wang
- Department of Ecology, College of Life Science, Wuhan University, Wuhan, China
| | - Dong Xie
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
- National Wetland Ecosystem Field Station of Taihu Lake, National Forestry Administration, Suzhou, China
| | - Juan Zhang
- Department of Ecology, College of Life Science, Wuhan University, Wuhan, China
| | - Pengsen Cai
- Department of Ecology, College of Life Science, Wuhan University, Wuhan, China
| | - Xing Li
- Department of Ecology, College of Life Science, Wuhan University, Wuhan, China
| | - Xinwei Xu
- Department of Ecology, College of Life Science, Wuhan University, Wuhan, China
| | - Tao Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jindong Zhao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- State Key Laboratory of Protein and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing, China
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19
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Mu XY, Wu YM, Shen XL, Tong L, Lei FW, Xia XF, Ning Y. Genomic Data Reveals Profound Genetic Structure and Multiple Glacial Refugia in Lonicera oblata (Caprifoliaceae), a Threatened Montane Shrub Endemic to North China. FRONTIERS IN PLANT SCIENCE 2022; 13:832559. [PMID: 35615142 PMCID: PMC9125190 DOI: 10.3389/fpls.2022.832559] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 03/21/2022] [Indexed: 05/28/2023]
Abstract
Characterizing genetic diversity and structure and identifying conservation units are both crucial for the conservation and management of threatened species. The development of high-throughput sequencing technology provides exciting opportunities for conservation genetics. Here, we employed the powerful SuperGBS method to identify 33, 758 high-quality single-nucleotide polymorphisms (SNP) from 134 individuals of a critically endangered montane shrub endemic to North China, Lonicera oblata. A low level of genetic diversity and a high degree of genetic differentiation among populations were observed based on the SNP data. Both principal component and phylogenetic analyses detected seven clusters, which correspond exactly to the seven geographic populations. Under the optimal K = 7, Admixture suggested the combination of the two small and geographically neighboring populations in the Taihang Mountains, Dongling Mountains, and Lijiazhuang, while the division of the big population of Jiankou Great Wall in the Yan Mountains into two clusters. High population genetic diversity and a large number of private alleles were detected in the four large populations, while low diversity and non-private alleles were observed for the remaining three small populations, implying the importance of these large populations as conservation units in priority. Demographic history inference suggested two drastic contractions of population size events that occurred after the Middle Pleistocene Transition and the Last Glacial Maximum, respectively. Combining our previous ecological niche modeling results with the present genomic data, there was a possible presence of glacial refugia in the Taihang and Yan Mountains, North China. This study provides valuable data for the conservation and management of L. oblata and broadens the understanding of the high biodiversity in the Taihang and Yan Mountains.
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Affiliation(s)
- Xian-Yun Mu
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Yuan-Mi Wu
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Xue-Li Shen
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Ling Tong
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Feng-Wei Lei
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Xiao-Fei Xia
- Beijing Museum of Natural History, Beijing, China
| | - Yu Ning
- Institute of Wetland Research, Chinese Academy of Forestry, Beijing, China
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20
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Wang Y, Ruhsam M, Milne R, Graham SW, Li J, Tao T, Zhang Y, Mao K. Incomplete lineage sorting and local extinction shaped the complex evolutionary history of the Paleogene relict conifer genus, Chamaecyparis (Cupressaceae). Mol Phylogenet Evol 2022; 172:107485. [PMID: 35452840 DOI: 10.1016/j.ympev.2022.107485] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 03/26/2022] [Accepted: 04/05/2022] [Indexed: 11/24/2022]
Abstract
Inferring accurate biogeographic history of plant taxa with an East Asia (EA)-North America (NA) is usually hindered by conflicting phylogenies and a poor fossil record. The current distribution of Chamaecyparis (false cypress; Cupressaceae) with four species in EA, and one each in western and eastern NA, and its relatively rich fossil record, make it an excellent model for studying the EA-NA disjunction. Here we reconstruct phylogenomic relationships within Chamaecyparis using > 1400 homologous nuclear and 61 plastid genes. Our phylogenomic analyses using concatenated and coalescent approaches revealed strong cytonuclear discordance and conflicting topologies between nuclear gene trees. Incomplete lineage sorting (ILS) and hybridization are possible explanations of conflict; however, our coalescent analyses and simulations suggest that ILS is the major contributor to the observed phylogenetic discrepancies. Based on a well-resolved species tree and four fossil calibrations, the crown lineage of Chamaecyparis is estimated to have originated in the upper Cretaceous, followed by diversification events in the early and middle Paleogene. Ancestral area reconstructions suggest that Chamaecyparis had an ancestral range spanning both EA and NA. Fossil records further indicate that this genus is a relict of the "boreotropical" flora, and that local extinctions of European species were caused by global cooling. Overall, our results unravel a complex evolutionary history of a Paleogene relict conifer genus, which may have involved ILS, hybridization and the extinction of local species.
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Affiliation(s)
- Yi Wang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Markus Ruhsam
- Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh EH3 5LR, UK
| | - Richard Milne
- Institute of Molecular Plant Science, School of Biological Science, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Sean W Graham
- Department of Botany, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Jialiang Li
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Tongzhou Tao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Yujiao Zhang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - Kangshan Mao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, China; College of Science, Tibet University, Lhasa 850000, Xizang Autonomous Region, PR China.
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21
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Wu S, Wang Y, Wang Z, Shrestha N, Liu J. Species divergence with gene flow and hybrid speciation on the Qinghai-Tibet Plateau. THE NEW PHYTOLOGIST 2022; 234:392-404. [PMID: 35020198 DOI: 10.1111/nph.17956] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 12/09/2021] [Indexed: 06/14/2023]
Abstract
The Qinghai-Tibet Plateau (QTP) sensu lato (sl), comprising the platform, the Himalaya and the Hengduan Mountains, is characterized by a large number of endemic plant species. This evolutionary cradle may have arisen from explosive species diversification because of geographic isolation. However, gene flow has been widely detected during the speciation processes of all groups examined, suggesting that natural selection may have also played an important role during species divergence in this region. In addition, natural hybrids have been recovered in almost all species-rich genera. This suggests that numerous species in this region are still 'on the speciation pathway to complete reproductive isolation (RI)'. Such hybrids could directly develop into new species through hybrid polyploidization and homoploid hybrid speciation (HHS). HHS may take place more easily than previously thought through alternate inheritance of alleles of parents at multiple RI loci. Therefore, isolation, selection and hybridization could together have promoted species diversification of numerous plant genera on the QTP sl. We emphasize the need for identification and functional analysis of alleles of major genes for speciation, and especially encourage investigations of parallel adaptive divergence causing RI across different lineages within similar but specific habitats in this region.
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Affiliation(s)
- Shengdan Wu
- State Key Laboratory of Grassland Agro-Ecosystems and College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Yi Wang
- Key Laboratory for Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Zefu Wang
- Key Laboratory for Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, China
| | - Nawal Shrestha
- State Key Laboratory of Grassland Agro-Ecosystems and College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Jianquan Liu
- State Key Laboratory of Grassland Agro-Ecosystems and College of Ecology, Lanzhou University, Lanzhou, 730000, China
- Key Laboratory for Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, China
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22
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Comparative Plastome Analysis of Three Amaryllidaceae Subfamilies: Insights into Variation of Genome Characteristics, Phylogeny, and Adaptive Evolution. BIOMED RESEARCH INTERNATIONAL 2022; 2022:3909596. [PMID: 35372568 PMCID: PMC8970886 DOI: 10.1155/2022/3909596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 01/19/2022] [Accepted: 02/05/2022] [Indexed: 11/17/2022]
Abstract
In the latest APG IV classification system, Amaryllidaceae is placed under the order of Asparagus and includes three subfamilies: Agapanthoideae, Allioideae, and Amaryllidoideae, which include many economically important crops. With the development of molecular phylogeny, research on the phylogenetic relationship of Amaryllidaceae has become more convenient. However, the current comparative analysis of Amaryllidaceae at the whole chloroplast genome level is still lacking. In this study, we sequenced 18 Allioideae plastomes and combined them with publicly available data (a total of 41 plastomes), including 21 Allioideae species, 1 Agapanthoideae species, 14 Amaryllidoideae species, and 5 Asparagaceae species. Comparative analyses were performed including basic characteristics of genome structure, codon usage, repeat elements, IR boundary, and genome divergence. Phylogenetic relationships were detected using single-copy genes (SCGs) and ribosomal internal transcribed spacer sequences (ITS), and the branch-site model was also employed to conduct the positive selection analysis. The results indicated that all Amaryllidaceae species showed a highly conserved typical tetrad structure. The GC content and five codon usage indexes in Allioideae species were lower than those in the other two subfamilies. Comparison analysis of Bayesian and ML phylogeny based on SCGs strongly supports the monophyly of three subfamilies and the sisterhood among them. Besides, positively selected genes (PSGs) were detected in each of the three subfamilies. Almost all genes with significant posterior probabilities for codon sites were associated with self-replication and photosynthesis. Our study investigated the three subfamilies of Amaryllidaceae at the whole chloroplast genome level and suggested the key role of selective pressure in the adaptation and evolution of Amaryllidaceae.
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23
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Sun QH, Morales-Briones DF, Wang HX, Landis JB, Wen J, Wang HF. Phylogenomic analyses of the East Asian endemic Abelia (Caprifoliaceae) shed insights into the temporal and spatial diversification history with widespread hybridization. ANNALS OF BOTANY 2022; 129:201-216. [PMID: 34950959 PMCID: PMC8796676 DOI: 10.1093/aob/mcab139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 11/15/2021] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS Abelia (Caprifoliaceae) is a small genus with five species, including one artificial hybrid and several natural hybrids. The genus has a discontinuous distribution in Mainland China, Taiwan Island and the Ryukyu Islands, providing a model system to explore the mechanisms of species dispersal in the East Asian flora. However, the current phylogenetic relationships within Abelia remain uncertain. METHODS We reconstructed the phylogenetic relationships within Abelia using nuclear loci generated by target enrichment and plastomes from genome skimming. Divergence time estimation, ancestral area reconstruction and ecological niche modelling (ENM) were used to examine the diversification history of Abelia. KEY RESULTS We found extensive cytonuclear discordance across the genus. By integrating lines of evidence from molecular phylogenies, divergence times and morphology, we propose to merge Abelia macrotera var. zabelioides into A. uniflora. Network analyses suggested that there have been multiple widespread hybridization events among Abelia species. These hybridization events may have contributed to the speciation mechanism and resulted in the high observed morphological diversity. The diversification of Abelia began in the early Eocene, followed by A. chinensis var. ionandra colonizing Taiwan Island during the Middle Miocene. The ENM results suggested an expansion of climatically suitable areas during the Last Glacial Maximum and range contraction during the Last Interglacial. Disjunction between the Himalayan-Hengduan Mountain region and Taiwan Island is probably the consequence of topographical isolation and postglacial contraction. CONCLUSIONS We used genomic data to reconstruct the phylogeny of Abelia and found a clear pattern of reticulate evolution in the group. In addition, our results suggest that shrinkage of postglacial range and the heterogeneity of the terrain have led to the disjunction between Mainland China and Taiwan Island. This study provides important new insights into the speciation process and taxonomy of Abelia.
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Affiliation(s)
- Qing-Hui Sun
- Key Laboratory of Tropical Biological Resources of Ministry of Education, College of Tropical Crops, Hainan University, Haikou, China
| | - Diego F Morales-Briones
- Department of Plant and Microbial Biology, College of Biological Sciences, University of Minnesota, 140 Gortner Laboratory, Saint Paul, MN, USA
- Systematics, Biodiversity and Evolution of Plants, Department of Biology I, Ludwig-Maximilians-Universität München, Menzinger Str. 67, 80638, Munich, Germany
| | - Hong-Xin Wang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, College of Tropical Crops, Hainan University, Haikou, China
- Zhai Mingguo Academician Work Station, Sanya University, Sanya, China
| | - Jacob B Landis
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, USA
- BTI Computational Biology Center, Boyce Thompson Institute, Ithaca, NY, USA
| | - Jun Wen
- Department of Botany, National Museum of Natural History, MRC-166, Smithsonian Institution, Washington, DC, USA
| | - Hua-Feng Wang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, College of Tropical Crops, Hainan University, Haikou, China
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24
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Xu B, Liao M, Deng HN, Yan CC, Lv YY, Gao YD, Ju WB, Zhang JY, Jiang LS, Li X, Gao XF. Chromosome-level de novo genome assembly and whole-genome resequencing of the threatened species Acanthochlamys bracteata (Velloziaceae) provide insights into alpine plant divergence in a biodiversity hotspot. Mol Ecol Resour 2021; 22:1582-1595. [PMID: 34837470 DOI: 10.1111/1755-0998.13562] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 11/07/2021] [Accepted: 11/18/2021] [Indexed: 11/27/2022]
Abstract
The Hengduan Mountains region is an important hotspot of alpine plant diversity and endemism. Acanthochlamys bracteata is a species of a threatened monotypic genus endemic to the Hengduan Mountains. In this study, we present a high-quality, chromosome-level reference genome for A. bracteata, constructed using long reads, short reads and Hi-C technology. We characterized its genetic diversity, population structure, demographic history and gene flow by resequencing individuals collected across its distribution. Comparative genomics analyses based on sequence information from single-copy orthologous genes revealed that A. bracteata and Dioscorea rotundata diverged ~104.5 million years ago. Whole-genome resequencing based on population genetic analysis revealed that the division of the 14 populations into 10 distinct clusters reflected geographical divergence, and three separate high levels of gene flow occurred sequentially between isolated populations of the Hengduan Mountains, a finding which is consistent with the turnover between ice ages and interglacial periods. Our findings indicate that Quaternary climatic changes played an important role in shaping the genetic structure and demographic trajectories of A. bracteata, and provide critical insights into the genetic status and evolutionary history of this poorly understood species, and possibly other alpine plants with a similar distribution. This study demonstrates the usefulness of population genomics for evaluating the effects of past climatic changes and identifying conservation units for the conservation and management of threatened species. Our high-quality genome represents a valuable resource for future studies of the underlying molecular mechanisms of adaptive evolution and provides insight for further comparative genomic analysis with other Velloziaceae species.
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Affiliation(s)
- Bo Xu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.,Mangkang Ecological Station, Tibet Ecological Safety Monitor Network, Changdu, China
| | - Min Liao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Heng-Ning Deng
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China
| | - Chao-Chao Yan
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China
| | - Yun-Yun Lv
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River, College of Life Sciences, Neijiang Normal University, Neijiang, China
| | - Yun-Dong Gao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Wen-Bin Ju
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jun-Yi Zhang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China
| | - Li-Sha Jiang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xiong Li
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xin-Fen Gao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu Institute of Biology, Chengdu, Sichuan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
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25
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Jiang Y, Ju T, Neaves LE, Li J, Tan W, Huang Y, Liu Y, Mao K. Distinct Genetic Structure Reflects Ploidy Level Differentiation in Newly Discovered, Extremely Small Populations of Xanthocyparis vietnamensis from Southwestern China. Front Genet 2021; 12:733576. [PMID: 34790221 PMCID: PMC8591046 DOI: 10.3389/fgene.2021.733576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/15/2021] [Indexed: 11/23/2022] Open
Abstract
Population genetic assessment is crucial for the conservation and management of threatened species. Xanthocyparis vietnamensis is an endangered species that is currently restricted to karst mountains in southwestern China and Vietnam. This rare conifer was first recorded in 2002 from northern Vietnam and then in 2013 from Guangxi, China, yet nothing is known about its genetic diversity nor ploidy level variation, although previous cytological study suggest that Vietnamese populations are tetraploids. There have been about 45 individuals found to date in Guangxi, China. Here, we genotyped 33 X. vietnamensis individuals using 20 newly developed, polymorphic microsatellite loci, to assess the genetic variability of its extremely small populations. The genetic diversity of X. vietnamensis (HE = 0.511) was lower than that of two other heliophile species, Calocedrus macrolepis and Fokienia hodginsii, which have similar distribution ranges. This is consistent with the signature of a genetic bottleneck detected in X. vietnamensis. Although the population genetic differentiation coefficient across loci is moderate (FST = 0.125), STRUCTURE analysis revealed two distinct genetic clusters, namely the northern and southern population groups; DAPC analysis grouped the southern populations together in one cluster separate from the northern populations; AMOVA analysis detected a significant genetic differentiation between the two population groups (FRT = 0.089, p < 0.05), and BARRIER analysis detected a genetic barrier between them. Moreover, we detected differentiation in ploidy level between northern and southern populations, sampled individuals from the former and the later are all diploid and tetraploid cytotypes with mean genome sizes of 26.08 and 48.02 pg/2C, respectively. We deduced that heterogeneous geomorphology and historical events (e.g., human deforestation, Quaternary climate oscillations) may have contributed to population fragmentation and small population size in X. vietnamensis. Considering both genetic and ploidy level differentiation, we propose that two different management units (northern and southern) should be considered and a combination of in situ and ex situ conservation measures should be employed to preserve populations of this endangered species in southwestern China in the light of our findings.
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Affiliation(s)
- Yuliang Jiang
- Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guangxi Institute of Botany, Guilin, China.,Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Tsam Ju
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Linda E Neaves
- Fenner School of Environment and Society, Australian National University, Canberra, ACT, Australia
| | - Jialiang Li
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Weining Tan
- Administration of Mulun National Nature Reserve of Guangxi, Huanjiang, China
| | - Yusong Huang
- Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guangxi Institute of Botany, Guilin, China
| | - Yan Liu
- Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guangxi Institute of Botany, Guilin, China
| | - Kangshan Mao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
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26
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Miao J, Farhat P, Wang W, Ruhsam M, Milne R, Yang H, Tso S, Li J, Xu J, Opgenoorth L, Miehe G, Mao K. Evolutionary history of two rare endemic conifer species from the eastern Qinghai-Tibet Plateau. ANNALS OF BOTANY 2021; 128:903-918. [PMID: 34472580 PMCID: PMC8577208 DOI: 10.1093/aob/mcab114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/01/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND AIMS Understanding the population genetics and evolutionary history of endangered species is urgently needed in an era of accelerated biodiversity loss. This knowledge is most important for regions with high endemism that are ecologically vulnerable, such as the Qinghai-Tibet Plateau (QTP). METHODS The genetic variation of 84 juniper trees from six populations of Juniperus microsperma and one population of Juniperus erectopatens, two narrow-endemic junipers from the QTP that are sister to each other, was surveyed using RNA-sequencing data. Coalescent-based analyses were used to test speciation, migration and demographic scenarios. Furthermore, positively selected and climate-associated genes were identified, and the genetic load was assessed for both species. KEY RESULTS Analyses of 149 052 single nucleotide polymorphisms showed that the two species are well differentiated and monophyletic. They diverged around the late Pliocene, but interspecific gene flow continued until the Last Glacial Maximum. Demographic reconstruction by Stairway Plot detected two severe bottlenecks for J. microsperma but only one for J. erectopatens. The identified positively selected genes and climate-associated genes revealed habitat adaptation of the two species. Furthermore, although J. microsperma had a much wider geographical distribution than J. erectopatens, the former possesses lower genetic diversity and a higher genetic load than the latter. CONCLUSIONS This study sheds light on the evolution of two endemic juniper species from the QTP and their responses to Quaternary climate fluctuations. Our findings emphasize the importance of speciation and demographic history reconstructions in understanding the current distribution pattern and genetic diversity of threatened species in mountainous regions.
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Affiliation(s)
- Jibin Miao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, PR China
- College of Science, Tibet University, Lhasa 850000, PR China
| | - Perla Farhat
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, PR China
- CEITEC – Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Wentao Wang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Markus Ruhsam
- Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh EH3 5LR, UK
| | - Richard Milne
- Institute of Molecular Plant Sciences, The University of Edinburgh, Edinburgh EH9 3JH, UK
| | - Heng Yang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Sonam Tso
- College of Science, Tibet University, Lhasa 850000, PR China
| | - Jialiang Li
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Jingjing Xu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Lars Opgenoorth
- Faculty of Biology and Geology, University of Marburg, 35032 Marburg, Germany
| | - Georg Miehe
- Faculty of Biology and Geology, University of Marburg, 35032 Marburg, Germany
| | - Kangshan Mao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, PR China
- College of Science, Tibet University, Lhasa 850000, PR China
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Li J, Zhang Y, Ruhsam M, Milne RI, Wang Y, Wu D, Jia S, Tao T, Mao K. Seeing through the hedge: Phylogenomics of Thuja (Cupressaceae) reveals prominent incomplete lineage sorting and ancient introgression for Tertiary relict flora. Cladistics 2021; 38:187-203. [PMID: 34551153 DOI: 10.1111/cla.12491] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 08/15/2021] [Accepted: 08/27/2021] [Indexed: 12/16/2022] Open
Abstract
The Eastern Asia (EA) - North America (NA) disjunction is a well-known biogeographic pattern of the Tertiary relict flora; however, few studies have investigated the evolutionary history of this disjunction using a phylogenomic approach. Here, we used 2369 single copy nuclear genes and nearly full plastomes to reconstruct the evolutionary history of the small Tertiary relict genus Thuja, which consists of five disjunctly distributed species. The nuclear species tree strongly supported an EA clade Thuja standishii-Thuja sutchuenensis and a "disjunct clade", where western NA species T. plicata is sister to an EA-eastern NA disjunct Thuja occidentalis-Thuja koraiensis group. Our results suggested that the observed topological discordance among the gene trees as well as the cytonuclear discordance is mainly due to incomplete lineage sorting, probably facilitated by the fast diversification of Thuja around the Early Miocene and the large effective population sizes of ancestral lineages. Furthermore, approximately 20% of the T. sutchuenensis nuclear genome is derived from an unknown ancestral lineage of Thuja, which might explain the close resemblance of its cone morphology to that of an ancient fossil species. Overall, our study demonstrates that single genes may not resolve interspecific relationships for disjunct taxa, and that more reliable results will come from hundreds or thousands of loci, revealing a more complex evolutionary history. This will steadily improve our understanding of their origin and evolution.
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Affiliation(s)
- Jialiang Li
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Yujiao Zhang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Markus Ruhsam
- Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh, EH3 5LR, UK
| | - Richard Ian Milne
- Institute of Molecular Plant Sciences, The University of Edinburgh, Edinburgh, EH9 3JH, UK
| | - Yi Wang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Dayu Wu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Shiyu Jia
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Tongzhou Tao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan, 610065, China
| | - Kangshan Mao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan, 610065, China.,College of Science, Tibet University, Lhasa, Xizang Autonomous Region, 850012, China
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Gene Flow and Diversification in Himalopsyche martynovi Species Complex (Trichoptera: Rhyacophilidae) in the Hengduan Mountains. BIOLOGY 2021; 10:biology10080816. [PMID: 34440048 PMCID: PMC8389565 DOI: 10.3390/biology10080816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 11/16/2022]
Abstract
The Hengduan Mountains are one of the most species-rich mountainous areas in the world. The origin and evolution of such a remarkable biodiversity are likely to be associated with geological or climatic dynamics, as well as taxon-specific biotic processes (e.g., hybridization, polyploidization, etc.). Here, we investigate the mechanisms fostering the diversification of the endemic Himalopsyche martynovi complex, a poorly known group of aquatic insects. We used multiple allelic datasets generated from 691 AHE loci to reconstruct species and RaxML phylogenetic trees. We selected the most reliable phylogenetic tree to perform network and gene flow analyses. The phylogenetic reconstructions and network analysis identified three clades, including H. epikur, H. martynovi sensu stricto and H. cf. martynovi. Himalopsyche martynovi sensu stricto and H. cf. martynovi present an intermediate morphology between H. epikur and H. viteceki, the closest known relative to the H. martynovi-complex. The gene flow analysis revealed extensive gene flow among these lineages. Our results suggest that H. viteceki and H. epikur are likely to have contributed to the evolution of H. martynovi sensu stricto and H. cf. martynovi via gene flow, and thus, our study provides insights in the diversification process of a lesser-known ecological group, and hints at the potential role of gene flow in the emergence of biological novelty in the Hengduan Mountains.
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Xie DF, Cheng RY, Fu X, Zhang XY, Price M, Lan YL, Wang CB, He XJ. A Combined Morphological and Molecular Evolutionary Analysis of Karst-Environment Adaptation for the Genus Urophysa (Ranunculaceae). FRONTIERS IN PLANT SCIENCE 2021; 12:667988. [PMID: 34177982 PMCID: PMC8223000 DOI: 10.3389/fpls.2021.667988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/12/2021] [Indexed: 06/13/2023]
Abstract
The karst environment is characterized by low soil water content, periodic water deficiency, and poor nutrient availability, which provides an ideal natural laboratory for studying the adaptive evolution of its inhabitants. However, how species adapt to such a special karst environment remains poorly understood. Here, transcriptome sequences of two Urophysa species (Urophysa rockii and Urophysa henryi), which are Chinese endemics with karst-specific distribution, and allied species in Semiaquilegia and Aquilegia (living in non-karst habitat) were collected. Single-copy genes (SCGs) were extracted to perform the phylogenetic analysis using concatenation and coalescent methods. Positively selected genes (PSGs) and clusters of paralogous genes (Mul_genes) were detected and subsequently used to conduct gene function annotation. We filtered 2,271 SCGs and the coalescent analysis revealed that 1,930 SCGs shared the same tree topology, which was consistent with the topology detected from the concatenated tree. Total of 335 PSGs and 243 Mul_genes were detected, and many were enriched in stress and stimulus resistance, transmembrane transport, cellular ion homeostasis, calcium ion transport, calcium signaling regulation, and water retention. Both molecular and morphological evidences indicated that Urophysa species evolved complex strategies for adapting to hostile karst environments. Our findings will contribute to a new understanding of genetic and phenotypic adaptive mechanisms of karst adaptation in plants.
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Affiliation(s)
- Deng-Feng Xie
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Rui-Yu Cheng
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Xiao Fu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Xiang-Yi Zhang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Megan Price
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Yan-Ling Lan
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | | | - Xing-Jin He
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
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30
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Stone BW, Wolfe AD. Phylogeographic analysis of shrubby beardtongues reveals range expansions during the Last Glacial Maximum and implicates the Klamath Mountains as a hotspot for hybridization. Mol Ecol 2021; 30:3826-3839. [PMID: 34013537 DOI: 10.1111/mec.15992] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 05/12/2021] [Accepted: 05/14/2021] [Indexed: 12/26/2022]
Abstract
Quaternary glacial cycles often altered species' geographic distributions, which in turn altered the geographic structure of species' genetic diversity. In many cases, glacial expansion forced species in temperate climates to contract their ranges and reside in small pockets of suitable habitat (refugia), where they were likely to interact closely with other species, setting the stage for potential gene exchange. These introgression events, in turn, would have degraded species boundaries, making the inference of phylogenetic relationships challenging. Using high-throughput sequence data, we employed a combination of species distribution models and hybridization tests to assess the effect of glaciation on the geographic distributions, phylogenetic relationships, and patterns of gene flow of five species of Penstemon subgenus Dasanthera, long-lived shrubby angiosperms distributed throughout the Pacific Northwest of North America. Surprisingly, we found that rather than reducing their ranges to small refugia, most Penstemon subgenus Dasanthera species experienced increased suitable habitat during the Last Glacial Maximum relative to the present day. We also found substantial evidence for gene exchange between species, with the bulk of introgression events occurring in or near the Klamath Mountains of southwestern Oregon and northwestern California. Subsequently, our phylogenetic inference reveals blurred taxonomic boundaries in the Klamath Mountains, where introgression is most prevalent. Our results question the classical paradigm of temperate species' responses to glaciation and highlight the importance of contextualizing phylogenetic inference with species' histories of introgression.
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Affiliation(s)
- Benjamin W Stone
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, USA
| | - Andrea D Wolfe
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, USA
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31
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Liu L, Wang Z, Su Y, Wang T. Population transcriptomic sequencing reveals allopatric divergence and local adaptation in Pseudotaxus chienii (Taxaceae). BMC Genomics 2021; 22:388. [PMID: 34039278 PMCID: PMC8157689 DOI: 10.1186/s12864-021-07682-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 05/05/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Elucidating the effects of geography and selection on genetic variation is critical for understanding the relative importance of adaptation in driving differentiation and identifying the environmental factors underlying its occurrence. Adaptive genetic variation is common in tree species, especially widely distributed long-lived species. Pseudotaxus chienii can occupy diverse habitats with environmental heterogeneity and thus provides an ideal material for investigating the process of population adaptive evolution. Here, we characterize genetic and expression variation patterns and investigate adaptive genetic variation in P. chienii populations. RESULTS We generated population transcriptome data and identified 13,545 single nucleotide polymorphisms (SNPs) in 5037 unigenes across 108 individuals from 10 populations. We observed lower nucleotide diversity (π = 0.000701) among the 10 populations than observed in other gymnosperms. Significant negative correlations between expression diversity and nucleotide diversity in eight populations suggest that when the species adapts to the surrounding environment, gene expression and nucleotide diversity have a reciprocal relationship. Genetic structure analyses indicated that each distribution region contains a distinct genetic group, with high genetic differentiation among them due to geographical isolation and local adaptation. We used FST outlier, redundancy analysis, and latent factor mixed model methods to detect molecular signatures of local adaptation. We identified 244 associations between 164 outlier SNPs and 17 environmental variables. The mean temperature of the coldest quarter, soil Fe and Cu contents, precipitation of the driest month, and altitude were identified as the most important determinants of adaptive genetic variation. Most candidate unigenes with outlier signatures were related to abiotic and biotic stress responses, and the monoterpenoid biosynthesis and ubiquitin-mediated proteolysis KEGG pathways were significantly enriched in certain populations and deserve further attention in other long-lived trees. CONCLUSIONS Despite the strong population structure in P. chienii, genomic data revealed signatures of divergent selection associated with environmental variables. Our research provides SNPs, candidate unigenes, and biological pathways related to environmental variables to facilitate elucidation of the genetic variation in P. chienii in relation to environmental adaptation. Our study provides a promising tool for population genomic analyses and insights into the molecular basis of local adaptation.
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Affiliation(s)
- Li Liu
- School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhen Wang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yingjuan Su
- School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
- Research Institute of Sun Yat-sen University in Shenzhen, Shenzhen, Guangdong, China.
| | - Ting Wang
- College of Life Sciences, South China Agricultural University, Guangzhou, Guangdong, China.
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32
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Chen C, Yang W, Liu J, Xi Z, Zhang L, Hu Q. Population Transcriptomics Reveals Gene Flow and Introgression Between Two Non-sister Alpine Gentians. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.638230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Distributional shifts driven by Quaternary climatic oscillations have been suggested to cause interspecific hybridization and introgression. In this study, we aimed to test this hypothesis by using population transcriptomes and coalescent modeling of two alpine none-sister gentians. Previous studies suggested that historical hybridizations occurred between Gentiana siphonantha and G. straminea in the high-altitude Qinghai-Tibet Plateau although both species are not sister to each other with the most recent divergence. In the present study, we sequenced transcriptomes of 33 individuals from multiple populations of G. siphonantha and G. straminea. The two species are well delimited by nuclear genomic SNPs while phylogenetic analyses of plastomes clustered one G. straminea individual into the G. siphonantha group. Further population structure analyses of the nuclear SNPs suggested that two populations of G. siphonantha were admixed with around 15% ancestry from G. straminea. These analyses suggested genetic introgressions from G. straminea to G. siphonantha. In addition, our coalescent-based modeling results revealed that gene flow occurred between the two species since Last Glacier Maximum after their initial divergence, which might have leaded to the observed introgressions. Our results underscore the significance of transcriptome population data in determining timescale of interspecific gene flow and direction of the resulting introgression.
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Zhang X, Rayner JG, Blaxter M, Bailey NW. Rapid parallel adaptation despite gene flow in silent crickets. Nat Commun 2021; 12:50. [PMID: 33397914 PMCID: PMC7782688 DOI: 10.1038/s41467-020-20263-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 11/23/2020] [Indexed: 12/13/2022] Open
Abstract
Gene flow is predicted to impede parallel adaptation via de novo mutation, because it can introduce pre-existing adaptive alleles from population to population. We test this using Hawaiian crickets (Teleogryllus oceanicus) in which 'flatwing' males that lack sound-producing wing structures recently arose and spread under selection from an acoustically-orienting parasitoid. Morphometric and genetic comparisons identify distinct flatwing phenotypes in populations on three islands, localized to different loci. Nevertheless, we detect strong, recent and ongoing gene flow among the populations. Using genome scans and gene expression analysis we find that parallel evolution of flatwing on different islands is associated with shared genomic hotspots of adaptation that contain the gene doublesex, but the form of selection differs among islands and corresponds to known flatwing demographics in the wild. We thus show how parallel adaptation can occur on contemporary timescales despite gene flow, indicating that it could be less constrained than previously appreciated.
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Affiliation(s)
- Xiao Zhang
- School of Biology, University of St Andrews, St Andrews, Fife, KY16 9TH, UK.
| | - Jack G Rayner
- School of Biology, University of St Andrews, St Andrews, Fife, KY16 9TH, UK
| | - Mark Blaxter
- Tree of Life, Wellcome Sanger Institute, Cambridge, CB10 1SA, UK
| | - Nathan W Bailey
- School of Biology, University of St Andrews, St Andrews, Fife, KY16 9TH, UK.
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Zhang X, Sun Y, Landis JB, Zhang J, Yang L, Lin N, Zhang H, Guo R, Li L, Zhang Y, Deng T, Sun H, Wang H. Genomic insights into adaptation to heterogeneous environments for the ancient relictual Circaeaster agrestis (Circaeasteraceae, Ranunculales). THE NEW PHYTOLOGIST 2020; 228:285-301. [PMID: 32426908 DOI: 10.1111/nph.16669] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 05/08/2020] [Indexed: 05/25/2023]
Abstract
Investigating the interaction between environmental heterogeneity and local adaptation is critical for understanding the evolutionary history of a species, providing the premise for studying the response of organisms to rapid climate change. However, for most species how exactly the spatial heterogeneity promotes population divergence and how genomic variations contribute to adaptive evolution remain poorly understood. We examine the contributions of geographical and environmental variables to population divergence of the relictual, alpine herb Circaeaster agrestis, as well as the genetic basis of local adaptation using RAD-seq and plastome data. We detected significant genetic structure with an extraordinary disequilibrium of genetic diversity among regions, and signals of isolation-by-distance along with isolation-by-resistance. The populations were estimated to begin diverging in the late Miocene, along with a possible ancestral distribution of the Hengduan Mountains and adjacent regions. Both environmental gradient and redundancy analyses revealed significant association between genetic variation and temperature variables. Genome-environment association analyses identified 16 putatively adaptive loci related mainly to biotic and abiotic stress resistance. Our genome-wide data provide new insights into the important role of environmental heterogeneity in shaping genetic structure, and access the footprints of local adaptation in an ancient relictual species, informing future conservation efforts.
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Affiliation(s)
- Xu Zhang
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanxia Sun
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
| | - Jacob B Landis
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, 92507, USA
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, 14850, USA
| | - Jianwen Zhang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Linsen Yang
- Hubei Key Laboratory of Shennongjia Golden Monkey Conservation Biology, Administration of Shennongjia National Park, Shennongjia, Hubei, 442400, China
| | - Nan Lin
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Huajie Zhang
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
| | - Rui Guo
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lijuan Li
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yonghong Zhang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Tao Deng
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Hang Sun
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, 650201, China
| | - Hengchang Wang
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
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Möller M, Liu J, Li Y, Li JH, Ye LJ, Mill R, Thomas P, Li DZ, Gao LM. Repeated intercontinental migrations and recurring hybridizations characterise the evolutionary history of yew (Taxus L.). Mol Phylogenet Evol 2020; 153:106952. [PMID: 32889136 DOI: 10.1016/j.ympev.2020.106952] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 07/19/2020] [Accepted: 08/28/2020] [Indexed: 12/24/2022]
Abstract
The genus Taxus (Taxaceae) consists of 16 genetically well-defined lineages that are predominantly distributed across the Northern hemisphere. We investigated its biogeographic origin and evolutionary history by sampling 13 chloroplast gene sequences, the nuclear internal transcribed spacers (ITS) and NEEDLY sequences for all 16 lineages. We applied Maximum Parsimony and Bayesian Inference analyses to infer their phylogenetic relationships, time-calibrated phylogenies using BEAST and inferred the ancestral area of occupancy with BioGeoBEARS. We found strong evidence for the hybrid origin of three lineages and dated these events to a rather narrow time window of 6.8-4.9 million years ago (Mya). The dated phylogenies inferred an Upper Cretaceous origin of the genus, with the extant lineages diversifying in North America much later during the Oligocene/early Miocene. Repeated migrations via the Bering land bridge to Eurasia and back were further inferred, with the return to North America as a possible result of vicariance. The diversification in Eurasia (from ~8 Mya onwards) coincided with the orogeny of the Hengduan Mountains, the intensification of the East Asian summer monsoon and the occupancy of ecological niches by lineages that experienced secondary contacts and hybridizations in the Hengduan Mountains and Qinling Mountain, especially around the Sichuan basin. We provide a hypothesis for the evolution of extant lineages of Taxus, a genus with an old and complex evolutionary history. The study highlights that the history of complex species can be unravelled with a careful dissection of phylogenetic signals.
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Affiliation(s)
- Michael Möller
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, United Kingdom.
| | - Jie Liu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Yan Li
- Institute of Alpine Economic Plants, Yunnan Academy of Agricultural Sciences, Lijiang, Yunnan 674100, China
| | - Jian-Hua Li
- Biology Department, Hope College, Holland, MI 49423, USA
| | - Lin-Jiang Ye
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Kunming College of Life Sciences, University of Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Robert Mill
- Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, United Kingdom
| | - Philip Thomas
- Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, United Kingdom
| | - De-Zhu Li
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Kunming College of Life Sciences, University of Chinese Academy of Sciences, Kunming, Yunnan 650201, China.
| | - Lian-Ming Gao
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China.
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