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Sun Y, Tian Y, Liu J, Li H, Lu J, Wang M, Liu S. Isolation and Identification of Colletotrichum nymphaeae as a Causal Agent of Leaf Spot on Rhododendron hybridum Ker Gawl and Its Effects on the Ultrastructure of Host Plants. J Fungi (Basel) 2025; 11:392. [PMID: 40422726 DOI: 10.3390/jof11050392] [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: 04/04/2025] [Revised: 05/14/2025] [Accepted: 05/15/2025] [Indexed: 05/28/2025] Open
Abstract
Rhododendron hybridum Ker Gawl, a widely cultivated horticultural species in China, is highly valued for its ornamental and medicinal properties. However, with the expansion of its cultivation, leaf spot disease has become more prevalent, significantly affecting the ornamental value of R. hybridum Ker Gawl. In this study, R. hybridum Ker Gawl from the Kunming area was selected as the experimental material. The tissue isolation method was employed in this study to isolate pathogenic strains. The biological characteristics of the pathogens were determined using the mycelial growth rate method. The pathogens' influence on the host plant's ultrastructure was investigated using transmission electron microscopy (TEM). Colletotrichum nymphaeae was identified as the pathogen implicated in the development of leaf spot disease in R. hybridum Ker Gawl across three regions in Kunming City through the integration of morphological traits and phylogenetic analyses of multiple genes (ITS, ACT, GAPDH, HIS3, CHS1, and TUB2). Its mycelial growth is most effective at a temperature of 25 °C. pH and light have relatively minor effects on the growth of mycelium. The preferred carbon and nitrogen sources were identified as mannitol and yeast extract, respectively. Additionally, TEM observations revealed significant damage to the cell structure of R. hybridum Ker Gawl leaves infected by the pathogen. The cell walls were dissolved, the number of chloroplasts decreased markedly, starch granules within chloroplasts were largely absent, and the number of osmiophilic granules increased. This is the first report of leaf spot disease in R. hybridum Ker Gawl caused by C. nymphaeae. The results of this study provide valuable insights for future research on the prevention and control of this disease.
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Affiliation(s)
- Yajiao Sun
- College of Landscape Architecture and Horticulture, Science, Southwest Forestry University, Kunming 650224, China
- Key Laboratory of Forest Disaster Warning and Control of Yunnan Province, Southwest Forestry University, Kunming 650224, China
| | - Yunjing Tian
- College of Landscape Architecture and Horticulture, Science, Southwest Forestry University, Kunming 650224, China
| | - Jian Liu
- College of Landscape Architecture and Horticulture, Science, Southwest Forestry University, Kunming 650224, China
- Key Laboratory of Forest Disaster Warning and Control of Yunnan Province, Southwest Forestry University, Kunming 650224, China
| | - Huali Li
- College of Landscape Architecture and Horticulture, Science, Southwest Forestry University, Kunming 650224, China
| | - Junjia Lu
- College of Landscape Architecture and Horticulture, Science, Southwest Forestry University, Kunming 650224, China
| | - Mengyao Wang
- College of Landscape Architecture and Horticulture, Science, Southwest Forestry University, Kunming 650224, China
| | - Shuwen Liu
- College of Landscape Architecture and Horticulture, Science, Southwest Forestry University, Kunming 650224, China
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Zhang XM, Cao YQ, Liu MX, Liu B, Zhou H, Xia YP, Wang XY. Phylogenetic and expression analysis of HSP20 gene family in Rhododendron species of different altitudes. Int J Biol Macromol 2025; 309:143125. [PMID: 40228764 DOI: 10.1016/j.ijbiomac.2025.143125] [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: 07/22/2024] [Revised: 04/11/2025] [Accepted: 04/11/2025] [Indexed: 04/16/2025]
Abstract
Small heat shock proteins (sHSPs/HSP20s) play important roles in regulating plant growth, development and stress responses, especially heat stress. Rhododendron plants are major components in landscaping or potting, but poor high-temperature tolerance limits their wide application. To elucidate the adaptive differences between Rhododendron species inhabiting high- and low-altitude regions, this study identified a total of 265 HSP20 genes across seven Rhododendron species, with categorizing into 11 subfamilies. In the CI subfamily, low-altitude Rhododendron species had more HSP20 genes than high-altitude species. Ka/Ks analysis indicated that nearly all HSP20 genes in the seven Rhododendron species have undergone purifying selection, with only a few in the low-altitude species exhibiting positive selection. Analysis of cis-acting elements revealed that most HSP20 genes in R. ovatum and R. simsii could respond to a variety of plant hormones and stresses. Expression pattern analysis revealed that HSP20 members are implicated in flower development and response to heat stress, with the CI subfamily being the main branch responsible for the heat stress response in low-altitude Rhododendron species. Heat stress treatment of transgenic yeast further validated the crucial role of CI subfamily genes in heat stress tolerance. This study provides the first analysis of evolutionary differences in the HSP20 gene families between high- and low-altitude Rhododendron species. It offers insights into the evolutionary direction of HSP20 genes and identifies key genes related to heat tolerance. Additionally, it highlights the role of CI subfamily genes in heat stress tolerance, contributing to the development of heat-tolerant Rhododendron varieties and advancing flower development research.
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Affiliation(s)
- Xiao-Mian Zhang
- Genomics and Genetic Engineering Laboratory of Ornamental Plants, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yu-Qing Cao
- Genomics and Genetic Engineering Laboratory of Ornamental Plants, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Meng-Xuan Liu
- Genomics and Genetic Engineering Laboratory of Ornamental Plants, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Bing Liu
- Department of plant pathology, Washington state University, Pullman, WA 99163, USA
| | - Hong Zhou
- Genomics and Genetic Engineering Laboratory of Ornamental Plants, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yi-Ping Xia
- Genomics and Genetic Engineering Laboratory of Ornamental Plants, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Xiu-Yun Wang
- Genomics and Genetic Engineering Laboratory of Ornamental Plants, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
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Wang Z, Qin K, Chen W, Ma G, Zhan Y, Zhu H, Wang H. High-Quality Genome Assembly and Transcriptome of Rhododendron platypodum Provide Insights into Its Evolution and Heat Stress Response. PLANTS (BASEL, SWITZERLAND) 2025; 14:1233. [PMID: 40284121 PMCID: PMC12030086 DOI: 10.3390/plants14081233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2025] [Revised: 04/11/2025] [Accepted: 04/16/2025] [Indexed: 04/29/2025]
Abstract
R. platypodum (Rhododendron platypodum) is an endangered alpine species with a highly restricted distribution in the southwestern region of China, which possesses significant ornamental and horticultural value. In this study, the high-quality genome assembly of R. platypodum at the chromosomal level is reported. The total genome size was determined to be 642.25 Mb, with a contig N50 of 25.64 Mb, and it contains 36,522 predicted genes. Comparative genomic analysis between R. platypodum and other species revealed the expansion of gene families, such as those related to transition metal ion binding and sodium ion transport, as well as the contraction of gene families involved in the recognition of pollen and pollen-pistil interaction. These findings might explain the adaptation of R. platypodum to rocky habitats and contribute to its endangered status. Furthermore, a heat stress experiment was conducted on R. platypodum, followed by transcriptome sequencing and physiological co-analysis to construct a co-expression network. This analysis identified the candidate gene TAR1-A and other transcription factors exhibiting differential expression under heat stress. The whole-genome sequencing, transcriptome analysis, and physiological co-analysis of R. platypodum provide valuable resources for its conservation and offer insights into its mechanisms of heat stress.
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Affiliation(s)
- Zizhuo Wang
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; (Z.W.); (K.Q.); (W.C.); (G.M.); (Y.Z.); (H.Z.)
| | - Kunrong Qin
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; (Z.W.); (K.Q.); (W.C.); (G.M.); (Y.Z.); (H.Z.)
- School of Architecture and Design, Chongqing College of Humanities, Science & Technology, Chongqing 401524, China
| | - Wentao Chen
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; (Z.W.); (K.Q.); (W.C.); (G.M.); (Y.Z.); (H.Z.)
| | - Guanpeng Ma
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; (Z.W.); (K.Q.); (W.C.); (G.M.); (Y.Z.); (H.Z.)
- Horticulture Institute, Guizhou Academy of Agricultural Sciences, Guizhou 550006, China
| | - Yu Zhan
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; (Z.W.); (K.Q.); (W.C.); (G.M.); (Y.Z.); (H.Z.)
| | - Haoxiang Zhu
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; (Z.W.); (K.Q.); (W.C.); (G.M.); (Y.Z.); (H.Z.)
| | - Haiyang Wang
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; (Z.W.); (K.Q.); (W.C.); (G.M.); (Y.Z.); (H.Z.)
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Wang X, Zhou P, Hu X, Bai Y, Zhang C, Fu Y, Huang R, Suzhen N, Song X. T2T genome, pan-genome analysis, and heat stress response genes in Rhododendron species. IMETA 2025; 4:e70010. [PMID: 40236772 PMCID: PMC11995181 DOI: 10.1002/imt2.70010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2024] [Revised: 02/17/2025] [Accepted: 02/19/2025] [Indexed: 04/17/2025]
Abstract
This study reports the first high-quality telomere-to-telomere (T2T) Rhododendron liliiflorum genome with 11 chromosomes that are gap free. The 24 telomeres and all 13 centromeres detected in this genome, which reached the highest quality gold level. In addition, other three Rhododendron species were sequenced and assembled to the chromosomal level. Based on 15 Rhododendron genomes, we conducted a pan-genome analysis of genus Rhododendron. Combining the genome and whole transcriptome sequencing, we identified several key genes and miRNAs related to the heat stress, which were further verified by transgenic experiments. Our findings provide rich resources for comparative and functional genomics studies of Rhododendron species.
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Affiliation(s)
- Xiaojing Wang
- Institute of Agro‐Bioengineering/The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in the Mountainous Region (Ministry of Education)/College of Life SciencesGuizhou UniversityGuiyangChina
| | - Ping Zhou
- Institute of Agro‐Bioengineering/The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in the Mountainous Region (Ministry of Education)/College of Life SciencesGuizhou UniversityGuiyangChina
| | - Xiaoyu Hu
- Institute of Agro‐Bioengineering/The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in the Mountainous Region (Ministry of Education)/College of Life SciencesGuizhou UniversityGuiyangChina
| | - Yun Bai
- School of Life Sciences/School of Basic Medical SciencesNorth China University of Science and TechnologyTangshanChina
| | - Chenhao Zhang
- School of Life Sciences/School of Basic Medical SciencesNorth China University of Science and TechnologyTangshanChina
| | - Yanhong Fu
- School of Life Sciences/School of Basic Medical SciencesNorth China University of Science and TechnologyTangshanChina
| | - Ruirui Huang
- Institute for Human GeneticsUniversity of California, San FranciscoSan FranciscoCaliforniaUSA
| | - Niu Suzhen
- Institute of Agro‐Bioengineering/The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in the Mountainous Region (Ministry of Education)/College of Life SciencesGuizhou UniversityGuiyangChina
| | - Xiaoming Song
- School of Life Sciences/School of Basic Medical SciencesNorth China University of Science and TechnologyTangshanChina
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Wen S, Cai X, Zhou K, Min Y, Shang C, Shen L, Deng L, Liu D, Qiao G, Shen X. Metabolome and comparative genome provide insights into secondary metabolites generation of a rare karst-growing Rhododendron in vitro culture. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2025; 121:e17235. [PMID: 39935165 DOI: 10.1111/tpj.17235] [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: 07/30/2024] [Accepted: 12/18/2024] [Indexed: 02/13/2025]
Abstract
Rhododendron species have the potential to be rich in secondary metabolites with pharmaceutical or industrial value. However, there is a lack of comprehensive metabolome studies at the genome level, particularly for unique and rare species like Rhododendron bailiense, which exclusively grows in karst environments in Guizhou, southwest China. Recently, genome assembly data for this species was available. In this study, nontargeted metabolomics was employed to investigate the secondary metabolites profile of R. bailiense callus. The callus of R. bailiense was induced using 0.2 mg L-1 TDZ (Thidiazuron) + 0.1 mg L-1 IBA (3-Indole butyric acid). A comparison between light-treated calli and dark-cultured calli revealed differential accumulation of metabolites, particularly in flavonoids, terpenoids, coumarins, and hydroxycinnamic acids, known for their beneficial effects such as antioxidant, anticancer, and anti-inflammatory properties. Proanthocyanidins, with various health-promoting effects, were found to accumulate significantly in dark-cultured calli. Light conditions promoted diterpene and triterpene products, whereas darkness favored sesquiterpene products. Additionally, the study demonstrated the potential of utilizing Agrobacterium transformation technology on callus suspension cells to enhance secondary metabolite production. Comparison with the genome of Rhododendron molle revealed that the R. bailiense genome exhibited active 'glycosyltransferase activity,' possessed a higher number of copies of monoterpene and sesquiterpene terpene synthases, and contained high copies of specific cytochrome P450 members (CYP71, CYP76, CYP79, CYP82, CYP736). This study offers valuable insights and potential strategies for the biosynthesis and production of Rhododendron secondary metabolites with pharmaceutical or industrial significance.
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Affiliation(s)
- Sulin Wen
- Department of Plant Science, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
- School of Design, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiaowei Cai
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
| | - Kui Zhou
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
| | - Yi Min
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
| | - Chunqiong Shang
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
| | - Luonan Shen
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
| | - Lin Deng
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
| | - Di Liu
- Majorbio Bio-Pharm Technology Co., Ltd, Shanghai, 201203, China
| | - Guang Qiao
- Key Laboratory of Mountain Plant Resources Protection and Germplasm Innovation (Ministry of Education), Institute of Agro-bioengineering/College of Life Sciences, Guizhou University, Guiyang, 550025, Guizhou Province, China
| | - Xiaohui Shen
- Department of Plant Science, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
- School of Design, Shanghai Jiao Tong University, Shanghai, 200240, China
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Ye Q, Zhang L, Li Q, Ji Y, Zhou Y, Wu Z, Hu Y, Ma Y, Wang J, Zhang C. Genome and GWAS analysis identified genes significantly related to phenotypic state of Rhododendron bark. HORTICULTURE RESEARCH 2024; 11:uhae008. [PMID: 38487544 PMCID: PMC10939351 DOI: 10.1093/hr/uhae008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 01/01/2024] [Indexed: 03/17/2024]
Abstract
As an important horticultural plant, Rhododendron is often used in urban greening and landscape design. However, factors such as the high rate of genetic recombination, frequent outcrossing in the wild, weak linkage disequilibrium, and the susceptibility of gene expression to environmental factors limit further exploration of functional genes related to important horticultural traits, and make the breeding of new varieties require a longer time. Therefore, we choose bark as the target trait which is not easily affected by environmental factors, but also has ornamental properties. Genome-wide association study (GWAS) of Rhododendron delavayi (30 samples), R. irroratum (30 samples) and their F1 generation R. agastum (200 samples) was conducted on the roughness of bark phenotypes. Finally, we obtained 2416.31 Gbp of clean data and identified 5 328 800 high-quality SNPs. According to the P-value and the degree of linkage disequilibrium of SNPs, we further identified 4 out of 11 candidate genes that affect bark roughness. The results of gene differential expression analysis further indicated that the expression levels of Rhdel02G0243600 and Rhdel08G0220700 in different bark phenotypes were significantly different. Our study identified functional genes that influence important horticultural traits of Rhododendron, and illustrated the powerful utility and great potential of GWAS in understanding and exploiting wild germplasm genetic resources of Rhododendron.
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Affiliation(s)
- Qiannan Ye
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Science, Kunming, Yunnan 650201, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lu Zhang
- Flower Research Institute of Yunnan Academy of Agricultural Sciences, National Engineering Research Center for Ornamental Horticulture, Yunnan Academy of Agricultural Sciences Kunming 650000, China
| | - Qing Li
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Science, Kunming, Yunnan 650201, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yaliang Ji
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Yanli Zhou
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Science, Kunming, Yunnan 650201, China
| | - Zhenzhen Wu
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Science, Kunming, Yunnan 650201, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanting Hu
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Science, Kunming, Yunnan 650201, China
| | - Yongpeng Ma
- Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Jihua Wang
- Flower Research Institute of Yunnan Academy of Agricultural Sciences, National Engineering Research Center for Ornamental Horticulture, Yunnan Academy of Agricultural Sciences Kunming 650000, China
| | - Chengjun Zhang
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Science, Kunming, Yunnan 650201, China
- Haiyan Engineering & Technology Center, Zhejiang Institute of Advanced Technology, Jiaxing 314022, China
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China
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Lyu ZY, Zhou XL, Wang SQ, Yang GM, Sun WG, Zhang JY, Zhang R, Shen SK. The first high-altitude autotetraploid haplotype-resolved genome assembled (Rhododendron nivale subsp. boreale) provides new insights into mountaintop adaptation. Gigascience 2024; 13:giae052. [PMID: 39110622 PMCID: PMC11304948 DOI: 10.1093/gigascience/giae052] [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: 12/19/2023] [Revised: 04/26/2024] [Accepted: 07/05/2024] [Indexed: 08/10/2024] Open
Abstract
BACKGROUND Rhododendron nivale subsp. boreale Philipson et M. N. Philipson is an alpine woody species with ornamental qualities that serve as the predominant species in mountainous scrub habitats found at an altitude of ∼4,200 m. As a high-altitude woody polyploid, this species may serve as a model to understand how plants adapt to alpine environments. Despite its ecological significance, the lack of genomic resources has hindered a comprehensive understanding of its evolutionary and adaptive characteristics in high-altitude mountainous environments. FINDINGS We sequenced and assembled the genome of R. nivale subsp. boreale, an assembly of the first subgenus Rhododendron and the first high-altitude woody flowering tetraploid, contributing an important genomic resource for alpine woody flora. The assembly included 52 pseudochromosomes (scaffold N50 = 42.93 Mb; BUSCO = 98.8%; QV = 45.51; S-AQI = 98.69), which belonged to 4 haplotypes, harboring 127,810 predicted protein-coding genes. Conjoint k-mer analysis, collinearity assessment, and phylogenetic investigation corroborated autotetraploid identity. Comparative genomic analysis revealed that R. nivale subsp. boreale originated as a neopolyploid of R. nivale and underwent 2 rounds of ancient polyploidy events. Transcriptional expression analysis showed that differences in expression between alleles were common and randomly distributed in the genome. We identified extended gene families and signatures of positive selection that are involved not only in adaptation to the mountaintop ecosystem (response to stress and developmental regulation) but also in autotetraploid reproduction (meiotic stabilization). Additionally, the expression levels of the (group VII ethylene response factor transcription factors) ERF VIIs were significantly higher than the mean global gene expression. We suspect that these changes have enabled the success of this species at high altitudes. CONCLUSIONS We assembled the first high-altitude autopolyploid genome and achieved chromosome-level assembly within the subgenus Rhododendron. In addition, a high-altitude adaptation strategy of R. nivale subsp. boreale was reasonably speculated. This study provides valuable data for the exploration of alpine mountaintop adaptations and the correlation between extreme environments and species polyploidization.
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Affiliation(s)
- Zhen-Yu Lyu
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming 650504 Yunnan, China
| | - Xiong-Li Zhou
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming 650504 Yunnan, China
| | - Si-Qi Wang
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming 650504 Yunnan, China
| | - Gao-Ming Yang
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming 650504 Yunnan, China
| | - Wen-Guang Sun
- School of Life Sciences, Yunnan Normal University, Kunming 650500 Yunnan, China
| | - Jie-Yu Zhang
- School of Life Sciences, Yunnan Normal University, Kunming 650500 Yunnan, China
| | - Rui Zhang
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming 650504 Yunnan, China
| | - Shi-Kang Shen
- Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming 650504 Yunnan, China
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