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Xu D, Wang T, Huang J, Wang Q, Wang Z, Xie Z, Zeng D, Liu X, Fu L. Comparative analysis of mitochondrial genomes of Stemona tuberosa lour. reveals heterogeneity in structure, synteny, intercellular gene transfer, and RNA editing. BMC PLANT BIOLOGY 2025; 25:23. [PMID: 39762746 PMCID: PMC11706144 DOI: 10.1186/s12870-024-06034-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2024] [Accepted: 12/30/2024] [Indexed: 01/11/2025]
Abstract
BACKGROUND Stemona tuberosa, a vital species in traditional Chinese medicine, has been extensively cultivated and utilized within its natural distribution over the past decades. While the chloroplast genome of S. tuberosa has been characterized, its mitochondrial genome (mitogenome) remains unexplored. RESULTS This paper details the assembly of the complete S. tuberosa mitogenome, achieved through the integration of Illumina and Nanopore sequencing technologies. The assembled mitogenome is 605,873 bp in size with a GC content of 45.63%. It comprises 66 genes, including 38 protein-coding genes, 25 tRNA genes, and 3 rRNA genes. Our analysis delved into codon usage, sequence repeats, and RNA editing within the mitogenome. Additionally, we conducted a phylogenetic analysis involving S. tuberosa and 17 other taxa to clarify its evolutionary and taxonomic status. This study provides a crucial genetic resource for evolutionary research within the genus Stemona and other related genera in the Stemonaceae family. CONCLUSION Our study provides the inaugural comprehensive analysis of the mitochondrial genome of S. tuberosa, revealing its unique multi-branched structure. Through our investigation of codon usage, sequence repeats, and RNA editing within the mitogenome, coupled with a phylogenetic analysis involving S. tuberosa and 17 other taxa, we have elucidated its evolutionary and taxonomic status. These investigations provide a crucial genetic resource for evolutionary research within the genus Stemona and other related genera in the Stemonaceae family.
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Affiliation(s)
- De Xu
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China
| | - Tao Wang
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China
| | - Juan Huang
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China
| | - Qiang Wang
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China
| | - Zhide Wang
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China
| | - Zhou Xie
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China
| | - Dequan Zeng
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China
| | - Xue Liu
- Chongqing Key Laboratory of Traditional Chinese Medicine Resource, Endangered Medicinal Breeding National Engineering Laboratory, Chongqing Academy of Chinese Materia Medica, Chongqing, 400065, China.
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, China.
| | - Liang Fu
- Dazhou Academy of Agricultural Sciences, Dazhou, 635000, China.
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Huang J, Hu X, Zhou Y, Peng YJ, Liu Z. Phylogeny, Genetic Diversity and Population Structure of Fritillaria cirrhosa and Its Relatives Based on Chloroplast Genome Data. Genes (Basel) 2024; 15:730. [PMID: 38927666 PMCID: PMC11202927 DOI: 10.3390/genes15060730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 05/30/2024] [Accepted: 05/30/2024] [Indexed: 06/28/2024] Open
Abstract
Fritillaria cirrhosa and its relatives have been utilized in traditional Chinese medicine for many years and are under priority protection in China. Despite their medicinal and protective value, research on their phylogeny, genetic diversity, and divergence remains limited. Here, we investigate the chloroplast genome variation architecture of 46 samples of F. cirrhosa and its relatives collected from various regions, encompassing the majority of wild populations across diverse geographical areas. The results indicate abundant variations in 46 accessions including 1659 single-nucleotide polymorphisms and 440 indels. Six variable markers (psbJ, ndhD, ycf1, ndhG, trnT-trnL, and rpl32-trnL) were identified. Phylogenetic and network analysis, population structure analysis, and principal component analysis showed that the 46 accessions formed five clades with significant divergence, which were related to their geographical distribution. The regions spanning from the southern Hengduan Mountains to the Qinghai-Tibet Plateau exhibited the highest levels of genetic diversity. F. cirrhosa and its relatives may have suffered a genetic bottleneck and have a relatively low genetic diversity level. Moreover, geographical barriers and discrete patches may have accelerated population divergence. The study offers novel perspectives on the phylogeny, genetic diversity, and population structure of F. cirrhosa and its relatives, information that can inform conservation and utilization strategies in the future.
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Affiliation(s)
- Jiao Huang
- College of Life Science, Leshan Normal University, Leshan 614000, China
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Han B, Tong B, Zhang J, Bu Z, Zhao L, Xian Y, Li D, Xie X. Genomic divergence and demographic history of Quercus aliena populations. BMC PLANT BIOLOGY 2024; 24:39. [PMID: 38195447 PMCID: PMC10775429 DOI: 10.1186/s12870-023-04623-y] [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: 06/19/2023] [Accepted: 11/20/2023] [Indexed: 01/11/2024]
Abstract
BACKGROUND Quercus aliena is a major montane tree species of subtropical and temperate forests in China, with important ecological and economic value. In order to reveal the species' population dynamics, genetic diversity, genetic structure, and association with mountain habitats during the evolutionary process, we re-sequenced the genomes of 72 Q. aliena individuals. RESULTS The whole chloroplast and nuclear genomes were used for this study. Phylogenetic analysis using the chloroplast genome dataset supported four clades of Q. aliena, while the nuclear dataset supported three major clades. Sex-biased dispersal had a critical role in causing discordance between the chloroplast and nuclear genomes. Population structure analysis showed two groups in Q. aliena. The effective population size sharply declined 1 Mya, coinciding with the Poyang Glaciation in Eastern China. Using genotype-climate association analyses, we found a positive correlation between allele frequency variation in SNPs and temperature, suggesting the species has the capacity to adapt to changing temperatures. CONCLUSION Overall, this study illustrates the genetic divergence, genomic variation, and evolutionary processes behind the demographic history of Q. aliena.
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Affiliation(s)
- Biao Han
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji'nan, 250102, Shandong, China
| | - Boqiang Tong
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji'nan, 250102, Shandong, China
| | - Jiliang Zhang
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji'nan, 250102, Shandong, China
| | - Ziheng Bu
- School of Life Sciences, Shandong University, Qingdao, 266237, Shandong, China
| | - Lijun Zhao
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji'nan, 250102, Shandong, China
| | - Yang Xian
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji'nan, 250102, Shandong, China
| | - Dezhu Li
- 3Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.
| | - Xiaoman Xie
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji'nan, 250102, Shandong, China.
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Marchesini A, Silverj A, Torre S, Rota-Stabelli O, Girardi M, Passeri I, Fracasso I, Sebastiani F, Vernesi C. First genome-wide data from Italian European beech (Fagus sylvatica L.): Strong and ancient differentiation between Alps and Apennines. PLoS One 2023; 18:e0288986. [PMID: 37471380 PMCID: PMC10358878 DOI: 10.1371/journal.pone.0288986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 07/10/2023] [Indexed: 07/22/2023] Open
Abstract
The European beech (Fagus sylvatica L.) is one of the most widespread forest trees in Europe whose distribution and intraspecific diversity has been largely shaped by repeated glacial cycles. Previous studies, mainly based on palaeobotanical evidence and a limited set of chloroplast and nuclear genetic markers, highlighted a complex phylogeographic scenario, with southern and western Europe characterized by a rather heterogeneous genetic structure, as a result of recolonization from different glacial refugia. Despite its ecological and economic importance, the genome of this broad-leaved tree has only recently been assembled, and its intra-species genomic diversity is still largely unexplored. Here, we performed whole-genome resequencing of nine Italian beech individuals sampled from two stands located in the Alpine and Apennine mountain ranges. We investigated patterns of genetic diversity at chloroplast, mitochondrial and nuclear genomes and we used chloroplast genomes to reconstruct a temporally-resolved phylogeny. Results allowed us to test European beech differentiation on a whole-genome level and to accurately date their divergence time. Our results showed comparable, relatively high levels of genomic diversity in the two populations and highlighted a clear differentiation at chloroplast, mitochondrial and nuclear genomes. The molecular clock analysis indicated an ancient split between the Alpine and Apennine populations, occurred between the Günz and the Riss glaciations (approximately 660 kyrs ago), suggesting a long history of separation for the two gene pools. This information has important conservation implications in the context of adaptation to ongoing climate changes.
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Affiliation(s)
- Alexis Marchesini
- Institute for Sustainable Plant Protection (IPSP), The National Research Council of Italy (CNR), Sesto Fiorentino (Florence), Italy
- Research Institute on Terrestrial Ecosystems (IRET), The National Research Council of Italy (CNR), Porano (Terni), Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Andrea Silverj
- Centre Agriculture Food Environment, University of Trento, San Michele all’Adige, Italy
- Department CIBIO, University of Trento, Trento, Italy
| | - Sara Torre
- Institute for Sustainable Plant Protection (IPSP), The National Research Council of Italy (CNR), Sesto Fiorentino (Florence), Italy
| | - Omar Rota-Stabelli
- Centre Agriculture Food Environment, University of Trento, San Michele all’Adige, Italy
- Department CIBIO, University of Trento, Trento, Italy
- Plant Protection Unit, Research and Innovation Centre, Fondazione Edmund Mach, S. Michele all’Adige (Trento), Italy
| | - Matteo Girardi
- Conservation Genomics Unit, Research and Innovation Centre- Fondazione Edmund Mach, S. Michele all’Adige (Trento), Italy
| | - Iacopo Passeri
- Institute for Sustainable Plant Protection (IPSP), The National Research Council of Italy (CNR), Sesto Fiorentino (Florence), Italy
| | - Ilaria Fracasso
- Forest Ecology Unit, Research and Innovation Centre- Fondazione Edmund Mach, S. Michele all’Adige (Trento), Italy
- Faculty of Science and Technology, Free University of Bolzano-Bozen, Bolzano, Italy
| | - Federico Sebastiani
- Institute for Sustainable Plant Protection (IPSP), The National Research Council of Italy (CNR), Sesto Fiorentino (Florence), Italy
| | - Cristiano Vernesi
- Forest Ecology Unit, Research and Innovation Centre- Fondazione Edmund Mach, S. Michele all’Adige (Trento), Italy
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Sun J, Wang Y, Qiao P, Zhang L, Li E, Dong W, Zhao Y, Huang L. Pueraria montana Population Structure and Genetic Diversity Based on Chloroplast Genome Data. PLANTS (BASEL, SWITZERLAND) 2023; 12:2231. [PMID: 37375857 DOI: 10.3390/plants12122231] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/24/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023]
Abstract
Despite having a generally conserved structure, chloroplast genome data have been helpful for plant population genetics and evolution research. To mine Pueraria montana chloroplast genome variation architecture and phylogeny, we investigated the chloroplast variation architecture of 104 P. montana accessions from across China. P. montana's chloroplast genome showed high diversity levels, with 1674 variations, including 1118 single nucleotide polymorphisms and 556 indels. The intergenic spacers, psbZ-trnS and ccsA-ndhD, are the two mutation hotspot regions in the P. montana chloroplast genome. Phylogenetic analysis based on the chloroplast genome dataset supported four P. montana clades. P. montana variations were conserved among and within clades, which showed high gene flow levels. Most P. montana clades were estimated to have diverged at 3.82-5.17 million years ago. Moreover, the East Asian summer monsoon and South Asian summer monsoon may have accelerated population divergence. Our results show that chloroplast genome sequences were highly variable and can be used as molecular markers to assess genetic variation and relationships in P. montana.
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Affiliation(s)
- Jiahui Sun
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
- Key Laboratory of Biology and Cultivation of Herb Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100700, China
| | - Yiheng Wang
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
- Key Laboratory of Biology and Cultivation of Herb Medicine, Ministry of Agriculture and Rural Affairs, Beijing 100700, China
| | - Ping Qiao
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Lei Zhang
- China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Enze Li
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
| | - Wenpan Dong
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
| | - Yuping Zhao
- China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Luqi Huang
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
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Maternal Donor and Genetic Variation of Lagerstroemia indica Cultivars. Int J Mol Sci 2023; 24:ijms24043606. [PMID: 36835020 PMCID: PMC9964644 DOI: 10.3390/ijms24043606] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/30/2022] [Accepted: 02/08/2023] [Indexed: 02/16/2023] Open
Abstract
Lagerstroemia indica L. is a well-known ornamental plant with large pyramidal racemes, long flower duration, and diverse colors and cultivars. It has been cultivated for nearly 1600 years and is essential for investigating the germplasm and assessing genetic variation to support international cultivar identification and breeding programs. In this study, 20 common Lagerstroemia indica cultivars from different varietal groups and flower morphologies, as well as multiple wild relative species, were analyzed to investigate the maternal donor of Lagerstroemia indica cultivars and to discover the genetic variation and relationships among cultivars based on plastome and nuclear ribosomal DNA (nrDNA) sequences. A total of 47 single nucleotide polymorphisms (SNPs) and 24 insertion/deletions (indels) were identified in the 20 L. indica cultivars' plastome and 25 SNPs were identified in the nrDNA. Phylogenetic analysis based on the plastome sequences showed that all the cultivars formed a clade with the species of L. indica, indicating that L. indica was the maternal donor of the cultivars. Population structure and PCA analyses supported two clades of cultivars, which exhibited significant genetic differences according to the plastome dataset. The results of the nrDNA supported that all 20 cultivars were divided into three clades and most of the cultivars had at least two genetic backgrounds and higher gene flow. Our results suggest that the plastome and nrDNA sequences can be used as molecular markers for assessing the genetic variation and relationships of L. indica cultivars.
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Li E, Liu K, Deng R, Gao Y, Liu X, Dong W, Zhang Z. Insights into the phylogeny and chloroplast genome evolution of Eriocaulon (Eriocaulaceae). BMC PLANT BIOLOGY 2023; 23:32. [PMID: 36639619 PMCID: PMC9840334 DOI: 10.1186/s12870-023-04034-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 01/02/2023] [Indexed: 05/13/2023]
Abstract
BACKGROUND Eriocaulon is a wetland plant genus with important ecological value, and one of the famous taxonomically challenging groups among angiosperms, mainly due to the high intraspecific diversity and low interspecific variation in the morphological characters of species within this genus. In this study, 22 samples representing 15 Eriocaulon species from China, were sequenced and combined with published samples of Eriocaulon to test the phylogenetic resolution using the complete chloroplast genome. Furthermore, comparative analyses of the chloroplast genomes were performed to investigate the chloroplast genome evolution of Eriocaulon. RESULTS The 22 Eriocaulon chloroplast genomes and the nine published samples were proved highly similar in genome size, gene content, and order. The Eriocaulon chloroplast genomes exhibited typical quadripartite structures with lengths from 150,222 bp to 151,584 bp. Comparative analyses revealed that four mutation hotspot regions (psbK-trnS, trnE-trnT, ndhF-rpl32, and ycf1) could serve as effective molecular markers for further phylogenetic analyses and species identification of Eriocaulon species. Phylogenetic results supported Eriocaulon as a monophyletic group. The identified relationships supported the taxonomic treatment of section Heterochiton and Leucantherae, and the section Heterochiton was the first divergent group. Phylogenetic tree supported Eriocaulon was divided into five clades. The divergence times indicated that all the sections diverged in the later Miocene and most of the extant Eriocaulon species diverged in the Quaternary. The phylogeny and divergence times supported rapid radiation occurred in the evolution history of Eriocaulon. CONCLUSION Our study mostly supported the taxonomic treatment at the section level for Eriocaulon species in China and demonstrated the power of phylogenetic resolution using whole chloroplast genome sequences. Comparative analyses of the Eriocaulon chloroplast genome developed molecular markers that can help us better identify and understand the evolutionary history of Eriocaulon species in the future.
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Affiliation(s)
- Enze Li
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Kangjia Liu
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Rongyan Deng
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Yongwei Gao
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Xinyu Liu
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Wenpan Dong
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
| | - Zhixiang Zhang
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
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Bartolucci F, Domina G, Adorni M, Andreatta S, Angiolini C, Bacchetta G, Banfi E, Barberis D, Bertani G, Bonari G, Buccomino G, Calvia G, Caputo P, Cavallaro V, Conti F, Cuena-Lombraña A, D’Aleo F, D’Amico FS, De Fine G, Del Guacchio E, De Matteis Tortora M, De Santis E, Fois M, Di Pietro F, Di Pietro R, Fanfarillo E, Fiaschi T, Forte L, Galasso G, Laface VL, Lallai A, Lonati M, Longo C, Longo D, Magrini M, Mei G, Menghi L, Menini F, Morabito A, Musarella CM, Nota G, Palermo DC, Passalacqua NG, Pazienza G, Peruzzi L, Pierini B, Pinzani L, Pisani G, Polverelli L, Prosser F, Salerno G, Salerno P, Santi F, Selvaggi A, Spampinato G, Stinca A, Terzi M, Valentini F, Vitale S, Wagensommer RP, Lastrucci L. Notulae to the Italian native vascular flora: 14. ITALIAN BOTANIST 2022. [DOI: 10.3897/italianbotanist.14.97813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, and status changes to the Italian administrative regions. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as Suppl. material 1.
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Selection of Elms Tolerant to Dutch Elm Disease in South-West Romania. DIVERSITY 2022. [DOI: 10.3390/d14110980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Ophoiostoma novo- ulmi continues to be one of the most dangerous invasive fungi, destroying many autochthonous elm forests and cultures throughout the world. Searching for natural genotypes tolerant to Dutch Elm Disease (DED) is one of the main objectives of silviculturists all over the northern hemisphere in order to save the susceptible elms and to restore their ecosystem biodiversity. In this regard, the first trial was established between 1991 and 1994, in south-west Romania (Pădurea Verde, Timișoara), using three elm species (Ulmus minor, U. glabra, and U. laevis) with 38 provenances. A local strain of Ophiostoma novo-ulmi was used to artificially inoculate all elm variants and the DED evolution was observed. Furthermore, in 2018–2021 the trial was inventoried to understand the local genotype reaction to DED in the local environmental conditions after almost 30 years. The outcomes of the present study proved the continuous presence of the infections in the comparative culture and its proximity, but the identified pathogen had a new hybrid form (found for the first time in Romania) between O. novo-ulmi ssp. Americana x O. novo-ulmi ssp. novo-ulmi. Wych elm (U. glabra) was extremely sensitive to DED: only 12 trees (out of 69 found in 2018) survived in 2021, and only one tree could be selected according to the adopted health criteria (resistance and vigour). The field elm (U. minor) was sensitive to the pathogen, but there were still individuals that showed good health status and growth. In contrast, the European white elm (U. laevis) proved constant tolerance to DED: only 15% had been found dead or presented severe symptoms of dieback. Overall, the results of this study report the diverse reactions of the Romanian regional elm genotypes to DED over the last three decades, providing promising perspectives for improving the presence of elms in the forest ecosystems of the Carpathian basin.
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