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Ruiz Mondragon KY, Aguirre-Planter E, Gasca-Pineda J, Klimova A, Trejo-Salazar RE, Reyes Guerra MA, Medellin RA, Piñero D, Lira R, Eguiarte LE. Conservation genomics of Agave tequilana Weber var. azul: low genetic differentiation and heterozygote excess in the tequila agave from Jalisco, Mexico. PeerJ 2022; 10:e14398. [PMID: 36415865 PMCID: PMC9676017 DOI: 10.7717/peerj.14398] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 10/24/2022] [Indexed: 11/18/2022] Open
Abstract
Background Genetic diversity is fundamental for the survival of species. In particular, in a climate change scenario, it is crucial that populations maintain genetic diversity so they can adapt to novel environmental conditions. Genetic diversity in wild agaves is usually high, with low genetic differentiation among populations, in part maintained by the agave pollinators such as the nectarivorous bats. In cultivated agaves, patterns of genetic diversity vary according to the intensity of use, management, and domestication stage. In Agave tequilana Weber var. azul (A. tequilana thereafter), the plant used for tequila production, clonal propagation has been strongly encouraged. These practices may lead to a reduction in genetic diversity. Methods We studied the diversity patterns with genome-wide SNPs, using restriction site associated DNA sequencing in cultivated samples of A. tequilana from three sites of Jalisco, Mexico. For one locality, seeds were collected and germinated in a greenhouse. We compared the genomic diversity, levels of inbreeding, genetic differentiation, and connectivity among studied sites and between adults and juvenile plants. Results Agave tequilana presented a genomic diversity of HT = 0.12. The observed heterozygosity was higher than the expected heterozygosity. Adults were more heterozygous than juveniles. This could be a consequence of heterosis or hybrid vigor. We found a shallow genetic structure (average paired FST = 0.0044). In the analysis of recent gene flow, we estimated an average migration rate among the different populations of m = 0.25. In particular, we found a population that was the primary source of gene flow and had greater genomic diversity (HE and HO ), so we propose that this population should continue to be monitored as a potential genetic reservoir. Discussion Our results may be the consequence of more traditional management in the studied specific region of Jalisco. Also, the exchange of seeds or propagules by producers and the existence of gene flow due to occasional sexual reproduction may play an important role in maintaining diversity in A. tequilana. For populations to resist pests, to continue evolving and reduce their risk of extinction under a climate change scenario, it is necessary to maintain genetic diversity. Under this premise we encourage to continue acting in conservation programs for this species and its pollinators.
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Affiliation(s)
| | - Erika Aguirre-Planter
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Jaime Gasca-Pineda
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Anastasia Klimova
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | | | | | - Rodrigo A. Medellin
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Daniel Piñero
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Rafael Lira
- Laboratorio de Recursos Naturales, Unidad de Biotecnología y Prototipos (UBIPRO), Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Luis E. Eguiarte
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
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Ruocco M, Jahnke M, Silva J, Procaccini G, Dattolo E. 2b-RAD Genotyping of the Seagrass Cymodocea nodosa Along a Latitudinal Cline Identifies Candidate Genes for Environmental Adaptation. Front Genet 2022; 13:866758. [PMID: 35651946 PMCID: PMC9149362 DOI: 10.3389/fgene.2022.866758] [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: 01/31/2022] [Accepted: 04/19/2022] [Indexed: 11/18/2022] Open
Abstract
Plant populations distributed along broad latitudinal gradients often show patterns of clinal variation in genotype and phenotype. Differences in photoperiod and temperature cues across latitudes influence major phenological events, such as timing of flowering or seed dormancy. Here, we used an array of 4,941 SNPs derived from 2b-RAD genotyping to characterize population differentiation and levels of genetic and genotypic diversity of three populations of the seagrass Cymodocea nodosa along a latitudinal gradient extending across the Atlantic-Mediterranean boundary (i.e., Gran Canaria—Canary Islands, Faro—Portugal, and Ebro Delta—Spain). Our main goal was to search for potential outlier loci that could underlie adaptive differentiation of populations across the latitudinal distribution of the species. We hypothesized that such polymorphisms could be related to variation in photoperiod-temperature regime occurring across latitudes. The three populations were clearly differentiated and exhibited diverse levels of clonality and genetic diversity. Cymodocea nodosa from the Mediterranean displayed the highest genotypic richness, while the Portuguese population had the highest clonality values. Gran Canaria exhibited the lowest genetic diversity (as observed heterozygosity). Nine SNPs were reliably identified as outliers across the three sites by two different methods (i.e., BayeScan and pcadapt), and three SNPs could be associated to specific protein-coding genes by screening available C. nodosa transcriptomes. Two SNPs-carrying contigs encoded for transcription factors, while the other one encoded for an enzyme specifically involved in the regulation of flowering time, namely Lysine-specific histone demethylase 1 homolog 2. When analyzing biological processes enriched within the whole dataset of outlier SNPs identified by at least one method, “regulation of transcription” and “signalling” were among the most represented. Our results highlight the fundamental importance signal integration and gene-regulatory networks, as well as epigenetic regulation via DNA (de)methylation, could have for enabling adaptation of seagrass populations along environmental gradients.
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Affiliation(s)
| | - Marlene Jahnke
- Department of Marine Sciences, Tjärnö Marine Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - João Silva
- Centre of Marine Sciences, University of Algarve, Faro, Portugal
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Tuya F, Fernández-Torquemada Y, Del Pilar-Ruso Y, Espino F, Manent P, Curbelo L, Otero-Ferrer F, de la Ossa JA, Royo L, Antich L, Castejón I, Máñez-Crespo J, Mateo-Ramírez Á, Procaccini G, Marco-Méndez C, Terrados J, Tomas F. Partitioning resilience of a marine foundation species into resistance and recovery trajectories. Oecologia 2021; 196:515-527. [PMID: 34009470 DOI: 10.1007/s00442-021-04945-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 05/11/2021] [Indexed: 12/01/2022]
Abstract
The resilience of an ecological unit encompasses resistance during adverse conditions and the capacity to recover. We adopted a 'resistance-recovery' framework to experimentally partition the resilience of a foundation species (the seagrass Cymodocea nodosa). The shoot abundances of nine seagrass meadows were followed before, during and after simulated light reduction conditions. We determined the significance of ecological, environmental and genetic drivers on seagrass resistance (% of shoots retained during the light deprivation treatments) and recovery (duration from the end of the perturbed state back to initial conditions). To identify whether seagrass recovery was linearly related to prior resistance, we then established the connection between trajectories of resistance and recovery. Finally, we assessed whether recovery patterns were affected by biological drivers (production of sexual products-seeds-and asexual propagation) at the meadow-scale. Resistance to shading significantly increased with the genetic diversity of the meadow and seagrass recovery was conditioned by initial resistance during shading. A threshold in resistance (here, at a ca. 70% of shoot abundances retained during the light deprivation treatments) denoted a critical point that considerably delays seagrass recovery if overpassed. Seed densities, but not rhizome elongation rates, were higher in meadows that exhibited large resistance and quick recovery, which correlated positively with meadow genetic diversity. Our results highlight the critical role of resistance to a disturbance for persistence of a marine foundation species. Estimation of critical trade-offs between seagrass resistance and recovery is a promising field of research to better manage impacts on seagrass meadows.
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Affiliation(s)
- Fernando Tuya
- Grupo en Biodiversidad y Conservación, IU-ECOAQUA, Universidad de Las Palmas de Gran Canaria, 35017, Las Palmas, Canary Islands, Spain.
| | | | - Yoana Del Pilar-Ruso
- Departamento de Ciencias del Mar y Biología Aplicada, Universidad de Alicante, Alicante, Spain
| | - Fernando Espino
- Grupo en Biodiversidad y Conservación, IU-ECOAQUA, Universidad de Las Palmas de Gran Canaria, 35017, Las Palmas, Canary Islands, Spain
| | - Pablo Manent
- Grupo en Biodiversidad y Conservación, IU-ECOAQUA, Universidad de Las Palmas de Gran Canaria, 35017, Las Palmas, Canary Islands, Spain
| | - Leticia Curbelo
- Grupo en Biodiversidad y Conservación, IU-ECOAQUA, Universidad de Las Palmas de Gran Canaria, 35017, Las Palmas, Canary Islands, Spain
| | - Francisco Otero-Ferrer
- Grupo en Biodiversidad y Conservación, IU-ECOAQUA, Universidad de Las Palmas de Gran Canaria, 35017, Las Palmas, Canary Islands, Spain
| | - Jose A de la Ossa
- Departamento de Ciencias del Mar y Biología Aplicada, Universidad de Alicante, Alicante, Spain
| | - Laura Royo
- Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB), C/ Miquel Marquès, 21, 07190, Esporles, Islas Baleares, Spain
| | - Laura Antich
- Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB), C/ Miquel Marquès, 21, 07190, Esporles, Islas Baleares, Spain
| | - Inés Castejón
- Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB), C/ Miquel Marquès, 21, 07190, Esporles, Islas Baleares, Spain
| | - Julia Máñez-Crespo
- Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB), C/ Miquel Marquès, 21, 07190, Esporles, Islas Baleares, Spain.,Universidad de Los Lagos, 5480000, Puerto Montt, Chile
| | - Ángel Mateo-Ramírez
- Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB), C/ Miquel Marquès, 21, 07190, Esporles, Islas Baleares, Spain.,GEMAR Group, Centro Oceanográfico de Málaga, Instituto Español de Oceanografía (IEO), Puerto Pesquero s/n, Apdo. 285, 29640, Fuengirola, Málaga, Spain
| | | | | | - Jorge Terrados
- Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB), C/ Miquel Marquès, 21, 07190, Esporles, Islas Baleares, Spain
| | - Fiona Tomas
- Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB), C/ Miquel Marquès, 21, 07190, Esporles, Islas Baleares, Spain
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Xu NN, Jiang K, Biswas SR, Tong X, Wang R, Chen XY. Clone Configuration and Spatial Genetic Structure of Two Halophila ovalis Populations With Contrasting Internode Lengths. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00170] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Yu S, Wu Y, Serrao EA, Zhang J, Jiang Z, Huang C, Cui L, Thorhaug A, Huang X. Fine-scale genetic structure and flowering output of the seagrass Enhalus acoroides undergoing disturbance. Ecol Evol 2019; 9:5186-5195. [PMID: 31110671 PMCID: PMC6509391 DOI: 10.1002/ece3.5106] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 03/01/2019] [Accepted: 03/04/2019] [Indexed: 12/04/2022] Open
Abstract
Seagrass are under great stress in the tropical coast of Asia, where Enhalus acoroides is frequently the dominant species with a large food web. Here, we investigate the question of the fine-scale genetic structure of this ecologically important foundation species, subject to severe anthropogenic disturbance in China. The genetic structure will illuminate potential mechanisms for population dynamics and sustainability, which are critical for preservation of biodiversity and for decision-making in management and restoration. We evaluated the fine-scale spatial genetic structure (SGS) and flowering output of E. acoroides, and indirectly estimated the relative importance of sexual versus asexual reproduction for population persistence using spatial autocorrelation analysis. Results reveal high clonal diversity for this species, as predicted from its high sexual reproduction output. The stronger Sp statistic at the ramet-level compared with genet-level indicates that clonality increases the SGS pattern for E. acoroides. Significant SGS at the genet-level may be explained by the aggregated dispersal of seed/pollen cohorts. The estimated gene dispersal variance suggests that dispersal mediated by sexual reproduction is more important than clonal growth in this study area. The ongoing anthropogenic disturbance will negatively affect the mating pattern and the SGS patterns in the future due to massive death of shoots, and less frequency of sexual reproduction.
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Affiliation(s)
- Shuo Yu
- Fourth Institute of OceanographyMinistry of Natural ResourcesBeihaiChina
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina
| | - Yunchao Wu
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina
- University of Chinese Academy of SciencesBeijingChina
| | | | - Jingping Zhang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina
| | - Zhijian Jiang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina
| | - Chi Huang
- Ocean University of ChinaQingdaoChina
| | - Lijun Cui
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina
- University of Chinese Academy of SciencesBeijingChina
| | - Anitra Thorhaug
- School of Forestry an Environmental StudiesYale UniversityNew HavenConnecticut
| | - Xiaoping Huang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina
- University of Chinese Academy of SciencesBeijingChina
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Marín-Guirao L, Bernardeau-Esteller J, García-Muñoz R, Ramos A, Ontoria Y, Romero J, Pérez M, Ruiz JM, Procaccini G. Carbon economy of Mediterranean seagrasses in response to thermal stress. MARINE POLLUTION BULLETIN 2018; 135:617-629. [PMID: 30301080 DOI: 10.1016/j.marpolbul.2018.07.050] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/16/2018] [Accepted: 07/19/2018] [Indexed: 05/27/2023]
Abstract
Increased plant mortality in temperate seagrass populations has been recently observed after summer heatwaves, although the underlying causes of plant death are yet unknown. The potential energetic constrains resulting from anomalous thermal events could be the reason that triggered seagrass mortality, as demonstrated for benthic invertebrates. To test this hypothesis, the carbon balance of Posidonia oceanica and Cymodocea nodosa plants from contrasting thermal environments was investigated during a simulated heatwave, by analyzing their photosynthetic performance, carbon balance (ratio photosynthesis:respiration), carbohydrates content, growth and mortality. Both species were able to overcome and recover from the thermal stress produced by the six-week exposure to temperatures 4 °C above mean summer levels, albeit plants from cold waters were more sensitive to warming than plants from warm waters as reflected by their inability to maintain their P:R ratio unaltered. The strategies through which plants tend to preserve their energetic status varied depending on the biology of the species and the thermal origin of plants. These included respiratory homeostasis (P. oceanica warm-plants), carbon diversion from growth to respiration (C. nodosa cold-plants) or storage (P. oceanica warm-plants) and changes in biomass allocation (C. nodosa warm-plants). Findings suggest an important geographic heterogeneity in the overall response of Mediterranean seagrasses to warming with potential negative impacts on the functions and services offered by seagrass meadows including among others their capacity for carbon sequestration and carbon export to adjacent ecosystems.
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Affiliation(s)
- L Marín-Guirao
- Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy.
| | - J Bernardeau-Esteller
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography C/Varadero, 30740 San Pedro del Pinatar, Murcia, Spain
| | - R García-Muñoz
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography C/Varadero, 30740 San Pedro del Pinatar, Murcia, Spain
| | - A Ramos
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography C/Varadero, 30740 San Pedro del Pinatar, Murcia, Spain
| | - Y Ontoria
- Department of Evolutionary Biology, Ecology, and Environmental Sciences, Universitat de Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain
| | - J Romero
- Department of Evolutionary Biology, Ecology, and Environmental Sciences, Universitat de Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain
| | - M Pérez
- Department of Evolutionary Biology, Ecology, and Environmental Sciences, Universitat de Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain
| | - J M Ruiz
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography C/Varadero, 30740 San Pedro del Pinatar, Murcia, Spain
| | - G Procaccini
- Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
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Van Tussenbroek BI, Valdivia‐Carrillo T, Rodríguez‐Virgen IT, Sanabria‐Alcaraz SNM, Jiménez‐Durán K, Van Dijk KJ, Marquez‐Guzmán GJ. Coping with potential bi-parental inbreeding: limited pollen and seed dispersal and large genets in the dioecious marine angiosperm Thalassia testudinum. Ecol Evol 2016; 6:5542-5556. [PMID: 27942375 PMCID: PMC5127610 DOI: 10.1002/ece3.2309] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 05/31/2016] [Accepted: 06/23/2016] [Indexed: 12/02/2022] Open
Abstract
The high prevalence of dioecy in marine angiosperms or seagrasses (>50% of all species) is thought to enforce cross-fertilization. However, seagrasses are clonal plants, and they may still be subject to sibling-mating or bi-parental inbreeding if the genetic neighborhood is smaller than the size of the genets. We tested this by determining the genetic neighborhoods of the dioecious seagrass Thalassia testudinum at two sites (Back-Reef and Mid-Lagoon) in Puerto Morelos Reef Lagoon, Mexico, by measuring dispersal of pollen and seeds in situ, and by fine-scale spatial autocorrelation analysis with eight polymorphic microsatellite DNA markers. Prevalence of inbreeding was verified by estimating pairwise kinship coefficients; and by analysing the genotypes of seedlings grown from seeds in mesocosms. Average dispersal of pollen was 0.3-1.6 m (max. 4.8 m) and of seeds was 0.3-0.4 m (max. 1.8 m), resulting in a neighborhood area of 7.4 m2 (range 3.4-11.4 m2) at Back-Reef and 1.9 (range 1.87-1.92 m2) at Mid-Lagoon. Neighborhood area (Na) derived from spatial autocorrelation was 0.1-20.5 m2 at Back-Reef and 0.1-16.9 m2 at Mid-Lagoon. Maximal extensions of the genets, in 19 × 30 m plots, were 19.2 m (median 7.5 m) and 10.8 m (median 4.8 m) at Back-Reef and Mid-Lagoon. There was no indication of deficit or excess of heterozygotes nor were coefficients of inbreeding (FIS) significant. The seedlings did not show statistically significant deficit of heterozygotes (except for 1 locus at Back-Reef). Contrary to our expectations, we did not find evidence of bi-parental inbreeding in this dioecious seagrass with large genets but small genetic neighborhoods. Proposed mechanisms to avoid bi-parental inbreeding are possible selection against homozygotes during fecundation or ovule development. Additionally, the genets grew highly dispersed (aggregation index Ac was 0.09 and 0.10 for Back-Reef and Mid-Lagoon, respectively); such highly dispersed guerrilla-like clonal growth form likely increases the probability of crossing between different potentially unrelated genets.
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Affiliation(s)
- Brigitta Ine Van Tussenbroek
- Instituto de Ciencias del Mar y LimnologíaUnidad Académica Sistemas Arrecifales‐Puerto MorelosUniversidad Nacional Autónoma de MéxicoProlongación Niños Héroes S/NPuerto MorelosQuintana RooMéxico
| | - Tania Valdivia‐Carrillo
- Instituto de Ciencias del Mar y LimnologíaUnidad Académica Sistemas Arrecifales‐Puerto MorelosUniversidad Nacional Autónoma de MéxicoProlongación Niños Héroes S/NPuerto MorelosQuintana RooMéxico
| | - Irene Teresa Rodríguez‐Virgen
- Instituto de Ciencias del Mar y LimnologíaUnidad Académica Sistemas Arrecifales‐Puerto MorelosUniversidad Nacional Autónoma de MéxicoProlongación Niños Héroes S/NPuerto MorelosQuintana RooMéxico
- Present address: Department of Life and Health SciencesUniversity of North Texas at DallasDallasTexas
| | - Sylvia Nashieli Marisela Sanabria‐Alcaraz
- Instituto de Ciencias del Mar y LimnologíaUnidad Académica Sistemas Arrecifales‐Puerto MorelosUniversidad Nacional Autónoma de MéxicoProlongación Niños Héroes S/NPuerto MorelosQuintana RooMéxico
| | - Karina Jiménez‐Durán
- Instituto de Ciencias del Mar y LimnologíaUnidad Académica Sistemas Arrecifales‐Puerto MorelosUniversidad Nacional Autónoma de MéxicoProlongación Niños Héroes S/NPuerto MorelosQuintana RooMéxico
- Facultad de CienciasLaboratorio de Desarrollo de PlantasCiudad UniversitariaUniversidad Nacional Autónoma de MéxicoCoyoacanDistrito FederalMéxico
| | - Kor Jent Van Dijk
- Instituto de Ciencias del Mar y LimnologíaUnidad Académica Sistemas Arrecifales‐Puerto MorelosUniversidad Nacional Autónoma de MéxicoProlongación Niños Héroes S/NPuerto MorelosQuintana RooMéxico
- Present address: School of Biological ScienceUniversity of AdelaideAdelaideSouth Australia5005Australia
| | - Guadalupe Judith Marquez‐Guzmán
- Facultad de CienciasLaboratorio de Desarrollo de PlantasCiudad UniversitariaUniversidad Nacional Autónoma de MéxicoCoyoacanDistrito FederalMéxico
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Ardehed A, Johansson D, Schagerström E, Kautsky L, Johannesson K, Pereyra RT. Complex spatial clonal structure in the macroalgae Fucus radicans with both sexual and asexual recruitment. Ecol Evol 2015; 5:4233-45. [PMID: 26664675 PMCID: PMC4667831 DOI: 10.1002/ece3.1629] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 07/03/2015] [Accepted: 07/08/2015] [Indexed: 11/19/2022] Open
Abstract
In dioecious species with both sexual and asexual reproduction, the spatial distribution of individual clones affects the potential for sexual reproduction and local adaptation. The seaweed Fucus radicans, endemic to the Baltic Sea, has separate sexes, but new attached thalli may also form asexually. We mapped the spatial distribution of clones (multilocus genotypes, MLGs) over macrogeographic (>500 km) and microgeographic (<100 m) scales in the Baltic Sea to assess the relationship between clonal spatial structure, sexual recruitment, and the potential for natural selection. Sexual recruitment was predominant in some areas, while in others asexual recruitment dominated. Where clones of both sexes were locally intermingled, sexual recruitment was nevertheless low. In some highly clonal populations, the sex ratio was strongly skewed due to dominance of one or a few clones of the same sex. The two largest clones (one female and one male) were distributed over 100–550 km of coast and accompanied by small and local MLGs formed by somatic mutations and differing by 1–2 mutations from the large clones. Rare sexual events, occasional long‐distance migration, and somatic mutations contribute new genotypic variation potentially available to natural selection. However, dominance of a few very large (and presumably old) clones over extensive spatial and temporal scales suggested that either these have superior traits or natural selection has only been marginally involved in the structuring of genotypes.
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Affiliation(s)
- Angelica Ardehed
- Department of Biology and Environmental Sciences University of Gothenburg Box 463, SE 405 30 Gothenburg Sweden
| | - Daniel Johansson
- Department of Biology and Environmental Sciences University of Gothenburg Box 463, SE 405 30 Gothenburg Sweden
| | - Ellen Schagerström
- Department of Ecology, Environment and Plant Sciences Stockholm University SE 106 91 Stockholm Sweden
| | - Lena Kautsky
- Department of Ecology, Environment and Plant Sciences Stockholm University SE 106 91 Stockholm Sweden
| | - Kerstin Johannesson
- Department of Marine Sciences-Tjärnö University of Gothenburg SE 452 96 Strömstad Sweden
| | - Ricardo T Pereyra
- Department of Marine Sciences-Tjärnö University of Gothenburg SE 452 96 Strömstad Sweden
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Radosavljević I, Satovic Z, Liber Z. Causes and consequences of contrasting genetic structure in sympatrically growing and closely related species. AOB PLANTS 2015; 7:plv106. [PMID: 26333826 PMCID: PMC4597123 DOI: 10.1093/aobpla/plv106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 08/14/2015] [Indexed: 05/29/2023]
Abstract
Gene flow, natural selection and genetic drift are processes that play a major role in shaping the genetic structure of natural populations. In addition, genetic structures of individual populations are strongly correlated with their geographical position within the species distribution area. The highest levels of genetic variation are usually found in the centre of a species' distribution and tend to decrease beyond that point. Additionally, narrowly endemic taxa are expected to be characterized by lower levels of genetic variation than their widespread congeners. To understand the historical circumstances that shape populations of sympatric and closely related taxa, microsatellite markers were used, while populations of the three closely related and sympatric Mediterranean Salvia species (S. officinalis L., S. fruticosa Mill. and S. brachyodon Vandas) served as a study model. In the populations of widespread S. officinalis, located in the central parts of this species' distribution area, no population genetic disturbances were detected. The narrow endemic S. brachyodon showed heterozygote excess, clonal reproduction and a genetic bottleneck. Because the genetic bottleneck was likely caused by the disappearance of suitable open-type habitats, the recent wildfire that cleared the terrain probably saved the S. brachyodon population from gradual deterioration and extinction. At the same time, clonal reproduction could serve as a valuable mechanism in the preservation of genetic variability. The results of the disjunct S. fruticosa population indicated heterozygote deficiency, inbreeding, hybridization with S. officinalis and population expansion. The hybridization with S. officinalis along with the abandonment of the agro-pastoral system are likely the main drivers of the strong expansion of S. fruticosa in the studied location. As many relevant findings and conclusions regarding historical and contemporary demography of individual populations or species can be reached only through their comparison with closely related taxa, this study demonstrates the importance and advantages of such a multi-species approach.
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Affiliation(s)
- Ivan Radosavljević
- Faculty of Science, Department of Botany, Division of Biology, University of Zagreb, Marulicev trg 9a, HR 10000 Zagreb, Croatia
| | - Zlatko Satovic
- Faculty of Agriculture, Department of Seed Science and Technology, University of Zagreb, Svetošimunska cesta 25, HR 10000 Zagreb, Croatia
| | - Zlatko Liber
- Faculty of Science, Department of Botany, Division of Biology, University of Zagreb, Marulicev trg 9a, HR 10000 Zagreb, Croatia
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Peng Y, Macek P, Macková J, Romoleroux K, Hensen I. Clonal Diversity and Fine-scale Genetic Structure in a High Andean Treeline Population. Biotropica 2014. [DOI: 10.1111/btp.12175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yanling Peng
- Institute of Biology/Geobotany and Botanical Garden; Martin Luther University of Halle-Wittenberg; Am Kirchtor 1 D-06108 Halle/Saale Germany
| | - Petr Macek
- Faculty of Science; University of South Bohemia; Branisovska 31 Ceske Budejovice CZ-37005 Czech Republic
- LINCGlobal; Estacion Experimental de Zonas Aridas; Consejo Superior de Investigaciones Cientificas; Ctra. Sacramento s/n La Canada de San Urbano E-04120 Almeria Spain
| | - Jana Macková
- Biology Centre AS CR; Institute of Soil Biology; Na Sadkach 7 Ceske Budejovice CZ-37005 Czech Republic
| | - Katya Romoleroux
- Herbario QCA; Escuela de Ciencias Biológicas; Pontificia Universidad Católica del Ecuador; Av. 12 de Octubre y Roca Apdo. 2184 Quito Ecuador
| | - Isabell Hensen
- Institute of Biology/Geobotany and Botanical Garden; Martin Luther University of Halle-Wittenberg; Am Kirchtor 1 D-06108 Halle/Saale Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig; Deutscher Platz 5e D-04103 Leipzig Germany
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Patsias K, Bruelheide H. Is the degree of clonality of forest herbs dependent on gap age? Using fingerprinting approaches to assess optimum successional stages for montane forest herbs. Ecol Evol 2012; 1:290-305. [PMID: 22393501 PMCID: PMC3287309 DOI: 10.1002/ece3.23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 07/22/2011] [Accepted: 07/28/2011] [Indexed: 11/16/2022] Open
Abstract
Using molecular fingerprinting (amplified fragment length polymorphism [AFLP] method), we explored the potential of small-scale population analysis for understanding colonization patterns of herb layer species in forests after canopy disturbance. We investigated three common forest understorey species with different life forms (Trientalis europaea, Calamagrostis villosa, and Vaccinium myrtillus) in the Harz Mountains in Germany in three different gap age classes and undisturbed forest. For two of them (T. europaea and C. villosa), we analyzed clone sizes and clonal structure. We hypothesized that clone sizes depend on age since gap formation and are affected by light availability. Mean patch sizes of V. myrtillus, T. europaea, and C. villosa formed were 3.7 m2, 27.9 m2, and 40.6 m2, respectively. Trientalis europaea and C. villosa patches consisted mostly of more than one genet. Largest clone sizes of T. europaea were encountered in gaps of intermediate successional age (15–60 years, averaged minimum estimation of clone sizes: 6.56 m2) whereas clone size of C. villosa was found to be independent from gap age and had a mean minimum clone size of 0.49 m2. In both species, clone size was positively related to light availability. Additionally, there was a positive relationship between clone size and ramet density for T. europaea and C. villosa. Genetic variation was higher within populations of T. europaea and C. villosa than among populations. Trientalis europaea was the only species with a clear genetic isolation by distance, pointing at an equilibrium between gene flow and genetic drift. In conclusion, we showed that forest canopy gap dynamics clearly affect the small-scale structure of populations of understorey plants. Species with high lateral growth rates, such as T. europaea offer the possibility to serve as “ecological clock” for dating ecological processes.
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Affiliation(s)
- Kathrin Patsias
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle Wittenberg Am Kirchtor 1, 06108 Halle (Saale), Germany
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Domingues R, Machado MA, Forzza RC, Melo TD, Wohlres-Viana S, Viccini LF. Genetic variability of an endangered Bromeliaceae species (Pitcairnia albiflos) from the Brazilian Atlantic rainforest. GENETICS AND MOLECULAR RESEARCH 2011; 10:2482-91. [PMID: 22009860 DOI: 10.4238/2011.october.13.5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Pitcairnia albiflos is a Bromeliaceae species endemic to Brazil that has been included as data-deficient in the extinction risk list of Brazilian flora. We analyzed genetic variability in P. albiflos populations using RAPD markers to investigate population structure and reproductive mechanisms and also to evaluate the actual extinction risk level of this species. Leaves of 56 individuals of P. albiflos from three populations were collected: Urca Hill (UH, 20 individuals), Chacrinha State Park (CSP, 24 individuals) and Tijuca National Park (TNP, 12 individuals). The RAPD technique was effective in characterizing the genetic diversity in the P. albiflos populations since it was possible to differentiate the populations and to identify exclusive bands for at least two of them. Even if there is low genetic diversity among them (CSP-UH = 0.463; CSP-TNP = 0.440; UH-TNP = 0.524), the populations seem to be isolated according to the low genetic diversity observed within them (H(pop) CSP = 0.060; H(pop) UH = 0.042; H(pop) TNP = 0.130). This fact might be the result of clonal and self-reproduction predominance and also from environmental degradation around the collection areas. Consequently, it would be important to protect all populations both in situ and ex situ to prevent the decrease of genetic variability. The low genetic variability among individuals of the same population confirms the inclusion of this species as critically endangered in the risk list for Brazilian flora.
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Affiliation(s)
- R Domingues
- Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
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Vallejo-Marín M, Dorken ME, Barrett SC. The Ecological and Evolutionary Consequences of Clonality for Plant Mating. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2010. [DOI: 10.1146/annurev.ecolsys.110308.120258] [Citation(s) in RCA: 217] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Mario Vallejo-Marín
- School of Biological and Environmental Sciences, University of Stirling, Scotland, FK9 4LA, United Kingdom;
| | - Marcel E. Dorken
- Department of Biology, Trent University, Petersborough, Ontario, K9J 7B8, Canada;
| | - Spencer C.H. Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, M5S 3B2; Canada;
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Fine-scale spatial structure of genets and sexes in the dioecious plant Dioscorea japonica, which disperses by both bulbils and seeds. Evol Ecol 2010. [DOI: 10.1007/s10682-010-9396-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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15
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Ohsako T. Clonal and spatial genetic structure within populations of a coastal plant, Carex kobomugi (Cyperaceae). AMERICAN JOURNAL OF BOTANY 2010; 97:458-470. [PMID: 21622409 DOI: 10.3732/ajb.0900262] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Clarification of clonal growth pattern is critical for understanding the population dynamics and reproductive system evolution of clonal plant species. The contribution of clonality to the spatial genetic structure (SGS) within populations is also an important issue. I examined the spatial distribution of genetic variability within two populations of the coastal plant Carex kobomugi using seven microsatellite loci. Genotyping of 226 and 140 ramets within 14 × 40 m and 14 × 34 m plots on two populations revealed 36 and 33 multilocus genotypes, respectively. To quantify the extent of intermingling among clones, for each genet, I calculated the dominance of ramets belonging to a particular genet within a spatial range of the genet. Furthermore, I analyzed spatial distribution of genotypes within 2 × 2 m and 1 × 2 m quadrats using second-order spatial statistics. These analyses indicated that clones are highly intermingled, suggesting a low level of spatial interaction among clones. Spatial autocorrelation analysis of kinship coefficient including all pairs of ramets showed significantly stronger SGS than analysis considering only pairs between different genets. I conclude that clonal propagation largely contributes to SGS at a fine scale.
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Affiliation(s)
- Takanori Ohsako
- Laboratory of Plant Resource Science, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 74 Kitainayazuma, Seika-cho, Kyoto 619-0244, Japan
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Araki K, Shimatani K, Ohara M. Dynamics of distribution and performance of ramets constructing genets: a demographic-genetic study in a clonal plant, Convallaria keiskei. ANNALS OF BOTANY 2009; 104:71-9. [PMID: 19376781 PMCID: PMC2706722 DOI: 10.1093/aob/mcp092] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
BACKGROUND AND AIMS In clonal plants producing vegetative offspring, performance at the genet level as well as at the ramet level should be investigated in order to understand the entire picture of the population dynamics and the life history characteristics. In this study, demography, including reproduction and survival, the growth patterns and the spatial distributions of ramets within genets of the clonal herb Convallaria keiskei were explored. METHODS Vegetative growth, flowering and survival of shoots whose genets were identified using microsatellite markers were monitored in four study plots for 3 years (2003-2005). The size structures of ramets in genets and their temporal shifts were then analysed. Their spatial distributions were also examined. KEY RESULTS During the census, 274 and 149 ramets were mapped in two 1 x 2 m plots, and 83 and 94 ramets in two 2 x 2 m quadrats. Thirty-eight genotypes were identified from 580 samples. Each plot included 5-18 genets, and most ramets belonged to the predominant genet(s) in each plot. Shoots foliated yearly for several years, but flowering ramets did not have an inflorescence the next year. A considerable number of new clonal offspring persistently appeared, forming a bell-shaped curve of the size structure of ramets in each genet. Comparing the structures modelled by the normal distributions suggested variation among ramets belonging to a single genet and variation among genets. Furthermore, spatial analyses revealed clumped and distant distributions of ramet pairs in a genet, in which the distant patterns corresponded to the linearly elongating clonal growth pattern of this species. CONCLUSION Characteristics of ramet performances such as flowering and recruitment of clonal offspring, in addition to growth, played a large part in the regulation of genet dynamics and distribution, which were different among the studied genets. These might be characteristics particularly relevant to clonal life histories.
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Affiliation(s)
- Kiwako Araki
- Course in Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan.
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Lin J, Gibbs JP, Smart LB. Population genetic structure of native versus naturalized sympatric shrub willows (Salix; Salicaceae). AMERICAN JOURNAL OF BOTANY 2009; 96:771-785. [PMID: 21628232 DOI: 10.3732/ajb.0800321] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Vegetative propagation of an introduced species can contribute significantly to its ability to spread and become naturalized, potentially in competition with native species. This study focused on the naturalization of a willow shrub, Salix purpurea, which was introduced to the United States from Europe and is commonly sympatric with the native shrub willow, S. eriocephala. Both species are capable of vegetative and sexual reproduction, but little is known about their relative frequency, nor the impact of clonal propagation on population-level genetic diversity. We analyzed genotypes at several microsatellite loci in 993 individuals belonging to 30 subpopulations of S. eriocephala and 28 subpopulations of S. purpurea in areas of sympatry across three watersheds to compare their genetic diversity and genetic structure. Our results revealed six subpopulations of S. purpurea containing plants with identical multilocus genotypes, while clonal individuals were rare among S. eriocephala populations. These species are dioecious with relatively high levels of heterozygosity, but S. eriocephala had much higher allelic diversity and genotypic diversity than did S. purpurea. These results strongly suggest that vegetative propagation has contributed to the naturalization of S. purpurea and has resulted in higher levels of genetic differentiation among S. purpurea populations than among native S. eriocephala populations.
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Affiliation(s)
- Juan Lin
- Department of Environmental and Forest Biology State University of New York College of Environmental Science and Forestry 246 Illick Hall, 1 Forestry Drive, Syracuse, New York 13210 USA
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Zipperle AM, Coyer JA, Reise K, Gitz E, Stam WT, Olsen JL. Clonal architecture in an intertidal bed of the dwarf eelgrass Zostera noltii in the Northern Wadden Sea: persistence through extreme physical perturbation and the importance of a seed bank. MARINE BIOLOGY 2009; 156:2139-2148. [PMID: 24391236 PMCID: PMC3873049 DOI: 10.1007/s00227-009-1244-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Accepted: 06/18/2009] [Indexed: 05/20/2023]
Abstract
Genotypic structure and temporal dynamics of the dwarf seagrass, Zostera noltii, were studied in an intertidal meadow that has persisted since prior to 1936 near the Wadden Sea island of Sylt. Samples were collected from two 10 × 10 m plots separated by 250 m from May 2002 to June 2005 and from four 1 × 1 m plots from June 2003 to September 2004. All the samples were genotyped with nine microsatellite loci. No genotypes were shared between the plots separated by 250 m. Genetic diversity was higher in the Wadden Sea than in the other regions of its geographic range. The average clone size (genets) (SD) in the two plots was 1.38 (0.26) and 1.46 (0.4) m², respectively, with a range up to 9 m² and <20% persisted for >4 years. A high genetic and genotypic diversity was maintained by annual recruitment of seedlings despite a dramatic decrease in ramet density that coincided with the severe heat stress event of 2003. Fine-scale (1 m²) analysis suggested that extensive loss of seagrass cover precluded space competition among the genets, while a persistent seed bank prevented local extinction. Long-term persistence of Z. noltii meadows in the intertidal Wadden Sea was achieved by high genet turnover and frequent seedling recruitment from a seed bank, in contrast to the low diversity observed in large and long-living clones of Z. noltii and other seagrasses in subtidal habitats.
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Affiliation(s)
- Andreas M. Zipperle
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, Biological Centre, University of Groningen, Kerklaan 30, 9750 AA Haren, The Netherlands
| | - James A. Coyer
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, Biological Centre, University of Groningen, Kerklaan 30, 9750 AA Haren, The Netherlands
| | - Karsten Reise
- Alfred Wegener Institute for Polar and Marine Research, Wadden Sea Station Sylt, 25992 List, Germany
| | - Eelo Gitz
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, Biological Centre, University of Groningen, Kerklaan 30, 9750 AA Haren, The Netherlands
| | - Wytze T. Stam
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, Biological Centre, University of Groningen, Kerklaan 30, 9750 AA Haren, The Netherlands
| | - Jeanine L. Olsen
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, Biological Centre, University of Groningen, Kerklaan 30, 9750 AA Haren, The Netherlands
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Wang Y, Li X, Guo J, Guo Z, Zhao G. Clonal diversity of Clintonia udensis Trautv. et Mey. populations and its correlation with ecological factors. SCIENCE IN CHINA. SERIES C, LIFE SCIENCES 2008; 51:575-582. [PMID: 18622740 DOI: 10.1007/s11427-008-0087-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Accepted: 05/21/2008] [Indexed: 05/26/2023]
Abstract
The clonal diversity of Clintonia udensis Trautv. et Mey. was detected by ISSR markers among 16 populations, and its correlation with ecological factors was analyzed as well in this work. Results showed that individuals (clonal ramets) per genotype were 1.12 and 1.149 at population and species levels, respectively, and that the 16 populations were all multiclonal. The detected genotypes were localized, without exception, within populations but demonstrated relatively high clonal differentiation among populations. The clonal diversity of the studied populations was high, with the average Simpson's index of 0.975, while the genets showed a clonal architecture of "guerilla". The population genetic diversities revealed by genet were consistent with those by ramet, further confirming their genetic differentiation among populations. And its genotype diversity within populations probably resulted largely from the frequent seedling regeneration and self-compatibility. In addition, the correlation analysis further revealed that, among the ecological factors, Simpson's index of C. udensis had a significant positive correlation (P<0.05) with pH values in the soil but not others.
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Affiliation(s)
- Yiling Wang
- Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), College of Life Sciences, Northwest University, Xi'an, 710069, China.
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Brun FG, Cummaudo F, Olivé I, Vergara JJ, Pérez-Lloréns JL. Clonal extent, apical dominance and networking features in the phalanx angiosperm Zostera noltii Hornem. MARINE BIOLOGY 2007; 151:1917-1927. [PMID: 30363820 PMCID: PMC6182604 DOI: 10.1007/s00227-007-0627-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Accepted: 01/17/2007] [Indexed: 05/29/2023]
Abstract
Disaggregating seagrass meadows and studying its components separately (clones, ramets, shoots) can provide us insights on meadow dynamics and growth patterns. The clonal growth, dependent upon clonal rules may regulate and impose constraints to plant architecture and, therefore, determine how individual clones evolve into the environment. In order to investigate the relationship between clonal growth rules and clone architecture, the belowground network architecture of single-clones of the seagrass Zostera noltii was studied. Networks were traced in situ after washing out the overlying sediment, and network characteristics were measured using digital analysis: area covered by clone, total rhizome length, type of rhizomatic axes (main, secondary, tertiary, quaternary), number and length of the internodes, branching angles and branching frequencies. This approach revealed that Z. noltii is able to develop into large clones integrating up to 300 internodes, 676 cm of rhizome, 208 shoots and 4,300 cm2 of plant area. Internodal length depended on both, the distance to the apical shoot (time effect) and the axes type (apical dominance effect). However, average branching angle was independent of axis type (average 58.3 ± 0.75), but varied significantly depending on the distance from the apical shoot. This average branching angle allows Z. noltii maximize the rate of centrifugal expansion, maintaining a high density in colonized areas to produce close stands but also minimizing the investment in belowground biomass and ramets overlapping. The clonal architecture of Z. noltii seems to be regulated by the interaction of both, apical dominance strength and clonal integration distance. Moreover, clonal growth rules and growth pattern seem to constrain clonality through (clonal) plant architecture regulations (i.e. branching is restricted in secondary axes, similar average branching angles regardless the axes, the higher the distance to the apex the higher the number of internodes in secondary axes, shorter internodes in secondary and tertiary axes). Future research efforts should focus on how these complex relationships between apical dominance and clonal integration interact to elucidate the temporal (seasonal) and spatial scales of both processes and the outcome at the plant architectural level.
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Affiliation(s)
- Fernando G. Brun
- Netherlands Institute of Ecology (NIOO-KNAW), Centre for Estuarine and Marine Ecology, Korringaweg 7, 4401 NT Yerseke, The Netherlands
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
| | - Fabio Cummaudo
- Ecology and Computational Hydrodynamics in Oceanography, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Borgo Grotta Gigante 42/C, 34010 Sgonico, Trieste, Italy
| | - Irene Olivé
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
| | - Juan José Vergara
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
| | - José Lucas Pérez-Lloréns
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
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Stoeckel S, Grange J, Fernández-Manjarres JF, Bilger I, Frascaria-Lacoste N, Mariette S. Heterozygote excess in a self-incompatible and partially clonal forest tree species -- Prunus avium L. Mol Ecol 2006; 15:2109-18. [PMID: 16780428 DOI: 10.1111/j.1365-294x.2006.02926.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Wild cherry (Prunus avium L.), a partially asexual self-incompatible forest tree, shows heterozygote excess, which is a poorly studied phenomenon. In three natural populations, we found significant heterozygote excess at almost all investigated loci (eight microsatellites and markers for the self-incompatibility locus). We examined four hypotheses to account for this observed heterozygote excess. First, negative F(IS) can result from a lack of selfed progeny in small populations of outcrossing species. A second explanation for negative F(IS) is selection during the life cycle of the most heterozygous individuals. A third explanation is negative assortative mating when reproduction occurs between individuals bearing phenotypes more dissimilar than by chance. The last explanation for negative F(IS) relies on asexual reproduction. Expectations for each hypothesis were tested using empirical data. Patterns of F(IS) differed among loci. Nevertheless, our experimental results did not confirm the small sample size hypothesis. Although one locus is probably under a hitch-hiking effect from the SI locus, we rejected the effect of the self-incompatibility locus for the genome as a whole. Similarly, although one locus showed a clear pattern consistent with the selection of heterozygous individuals, the heterosis effect over the whole genome was rejected. Finally, our results revealed that clonality probably explains significant negative F(IS) in wild cherry populations when considering all individuals. More theoretical effort is needed to develop expectations and hypotheses, and test them in the case of species combining self-incompatibility and partially asexual reproduction.
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Affiliation(s)
- Solenn Stoeckel
- Cemagref, Unité de Recherche 'Ecosystèmes Forestiers', Domaine des Barres, 45290 Nogent-sur-Vernisson, France.
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McGlaughlin ME, Friar EA. Clonality in the Endangered Ambrosia pumila (Asteraceae) Inferred from RAPD Markers; Implications for Conservation and Management. CONSERV GENET 2006. [DOI: 10.1007/s10592-006-9171-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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