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Manyara D, Sánchez-García M, Montoliu-Nerin M, Rosling A. Detection of rare variants among nuclei populating the arbuscular mycorrhizal fungal model species Rhizophagus irregularis DAOM197198. G3 (Bethesda) 2024:jkae074. [PMID: 38656424 DOI: 10.1093/g3journal/jkae074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 03/27/2024] [Indexed: 04/26/2024]
Abstract
Identifying genuine polymorphic variants is a significant challenge in sequence data analysis, although detecting low-frequency variants in sequence data is essential for estimating demographic parameters and investigating genetic processes, such as selection, within populations. Arbuscular mycorrhizal (AM) fungi are multinucleate organisms, in which individual nuclei collectively operate as a population, and the extent of genetic variation across nuclei has long been an area of scientific interest. In this study, we investigated the patterns of polymorphism discovery and the alternate allele frequency distribution by comparing polymorphism discovery in 2 distinct genomic sequence datasets of the AM fungus model species, Rhizophagus irregularis strain DAOM197198. The 2 datasets used in this study are publicly available and were generated either from pooled spores and hyphae or amplified single nuclei from a single spore. We also estimated the intraorganismal variation within the DAOM197198 strain. Our results showed that the 2 datasets exhibited different frequency patterns for discovered variants. The whole-organism dataset showed a distribution spanning low-, intermediate-, and high-frequency variants, whereas the single-nucleus dataset predominantly featured low-frequency variants with smaller proportions in intermediate and high frequencies. Furthermore, single nucleotide polymorphism density estimates within both the whole organism and individual nuclei confirmed the low intraorganismal variation of the DAOM197198 strain and that most variants are rare. Our study highlights the methodological challenges associated with detecting low-frequency variants in AM fungal whole-genome sequence data and demonstrates that alternate alleles can be reliably identified in single nuclei of AM fungi.
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Affiliation(s)
- David Manyara
- Department of Ecology and Genetics, Uppsala University, Uppsala 752 36, Sweden
| | - Marisol Sánchez-García
- Department of Ecology and Genetics, Uppsala University, Uppsala 752 36, Sweden
- Uppsala Biocentre, Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala 750 07, Sweden
| | - Merce Montoliu-Nerin
- Department of Ecology and Genetics, Uppsala University, Uppsala 752 36, Sweden
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Madrid 28223, Spain
| | - Anna Rosling
- Department of Ecology and Genetics, Uppsala University, Uppsala 752 36, Sweden
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van Creij J, Auxier B, An J, Wijfjes RY, Bergin C, Rosling A, Bisseling T, Pan Z, Limpens E. Stochastic nuclear organization and host-dependent allele contribution in Rhizophagus irregularis. BMC Genomics 2023; 24:53. [PMID: 36709253 PMCID: PMC9883914 DOI: 10.1186/s12864-023-09126-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 01/10/2023] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Arbuscular mycorrhizal (AM) fungi are arguably the most important symbionts of plants, offering a range of benefits to their hosts. However, the provisioning of these benefits does not appear to be uniform among AM fungal individuals, with genetic variation between fungal symbionts having a substantial impact on plant performance. Interestingly, genetic variation has also been reported within fungal individuals, which contain millions of haploid nuclei sharing a common cytoplasm. In the model AM fungus, Rhizophagus irregularis, several isolates have been reported to be dikaryotes, containing two genetically distinct types of nuclei recognized based on their mating-type (MAT) locus identity. However, their extremely coenocytic nature and lack of a known single nucleus stage has raised questions on the origin, distribution and dynamics of this genetic variation. RESULTS Here we performed DNA and RNA sequencing at the mycelial individual, single spore and single nucleus levels to gain insight into the dynamic genetic make-up of the dikaryote-like R. irregularis C3 isolate and the effect of different host plants on its genetic variation. Our analyses reveal that parallel spore and root culture batches can have widely variable ratios of two main genotypes in C3. Additionally, numerous polymorphisms were found with frequencies that deviated significantly from the general genotype ratio, indicating a diverse population of slightly different nucleotypes. Changing host plants did not show consistent host effects on nucleotype ratio's after multiple rounds of subculturing. Instead, we found a major effect of host plant-identity on allele-specific expression in C3. CONCLUSION Our analyses indicate a highly dynamic/variable genetic organization in different isolates of R. irregularis. Seemingly random fluctuations in nucleotype ratio's upon spore formation, recombination events, high variability of non-tandemly repeated rDNA sequences and host-dependent allele expression all add levels of variation that may contribute to the evolutionary success of these widespread symbionts.
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Affiliation(s)
- Jelle van Creij
- grid.4818.50000 0001 0791 5666Laboratory of Molecular Biology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, Wageningen, The Netherlands
| | - Ben Auxier
- grid.4818.50000 0001 0791 5666Laboratory of Genetics, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, Wageningen, The Netherlands
| | - Jianyong An
- grid.4818.50000 0001 0791 5666Laboratory of Molecular Biology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, Wageningen, The Netherlands ,grid.411626.60000 0004 1798 6793Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing University of Agriculture, Beijing, 102206 China
| | - Raúl Y. Wijfjes
- grid.4818.50000 0001 0791 5666Laboratory of Bioinformatics, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, Wageningen, The Netherlands ,grid.5252.00000 0004 1936 973XCurrent affiliation: Faculty of Biology, Ludwig Maximilian University of Munich, Munich, Germany
| | - Claudia Bergin
- grid.8993.b0000 0004 1936 9457Department of Cell and Molecular Biology, Uppsala University, and Microbial Single Cell Genomics Facility, Science for Life Laboratory, Uppsala, Sweden
| | - Anna Rosling
- grid.8993.b0000 0004 1936 9457Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, SE-75236 Uppsala, Sweden
| | - Ton Bisseling
- grid.4818.50000 0001 0791 5666Laboratory of Molecular Biology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, Wageningen, The Netherlands ,grid.411626.60000 0004 1798 6793Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing University of Agriculture, Beijing, 102206 China
| | - Zhiyong Pan
- grid.35155.370000 0004 1790 4137Key Laboratory of Horticultural Plant Biology (Ministry of Education), Key Laboratory of Horticultural Crop Biology and Genetic Improvement (Central Region, Ministry of Agriculture), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, People’s Republic of China
| | - Erik Limpens
- grid.4818.50000 0001 0791 5666Laboratory of Molecular Biology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, Wageningen, The Netherlands
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3
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Mateus ID, Auxier B, Ndiaye MMS, Cruz J, Lee SJ, Sanders IR. Reciprocal recombination genomic signatures in the symbiotic arbuscular mycorrhizal fungi Rhizophagus irregularis. PLoS One 2022; 17:e0270481. [PMID: 35776745 PMCID: PMC9249182 DOI: 10.1371/journal.pone.0270481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 06/12/2022] [Indexed: 11/24/2022] Open
Abstract
Arbuscular mycorrhizal fungi (AMF) are part of the most widespread fungal-plant symbiosis. They colonize at least 80% of plant species, promote plant growth and plant diversity. These fungi are multinucleated and contain either one or two haploid nuclear genotypes (monokaryon and dikaryon) identified by the alleles at a putative mating-type locus. This taxon has been considered as an ancient asexual scandal because of the lack of observable sexual structures. Despite identification of a putative mating-type locus and functional activation of genes related to mating when two isolates co-exist, it remains unknown if the AMF life cycle involves a sexual or parasexual stage. We used publicly available genome sequences to test if Rhizophagus irregularis dikaryon genomes display signatures of sexual reproduction in the form of reciprocal recombination patterns, or if they display exclusively signatures of parasexual reproduction involving gene conversion. We used short-read and long-read sequence data to identify nucleus-specific alleles within dikaryons and then compared them to orthologous gene sequences from related monokaryon isolates displaying the same putative MAT-types as the dikaryon. We observed that the two nucleus-specific alleles of the dikaryon A5 are more related to the homolog sequences of monokaryon isolates displaying the same putative MAT-type than between each other. We also observed that these nucleus-specific alleles displayed reciprocal recombination signatures. These results confirm that dikaryon and monokaryon isolates displaying the same putative MAT-type are related in their life-cycle. These results suggest that a genetic exchange mechanism, involving reciprocal recombination in dikaryon genomes, allows AMF to generate genetic diversity.
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Affiliation(s)
- Ivan D. Mateus
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
- * E-mail:
| | - Ben Auxier
- Laboratory of Genetics, Wageningen University, Wageningen, The Netherlands
| | - Mam M. S. Ndiaye
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Joaquim Cruz
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Soon-Jae Lee
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Ian R. Sanders
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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Frew A, Antunes PM, Cameron DD, Hartley SE, Johnson SN, Rillig MC, Bennett AE. Plant herbivore protection by arbuscular mycorrhizas: a role for fungal diversity? New Phytol 2022; 233:1022-1031. [PMID: 34618922 DOI: 10.1111/nph.17781] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 10/03/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Adam Frew
- School of Sciences, University of Southern Queensland, Toowoomba, Qld, 4350, Australia
- Centre for Crop Health, University of Southern Queensland, Toowoomba, Qld, 4350, Australia
| | - Pedro M Antunes
- Department of Biology, Algoma University, Sault Ste. Marie, ON, P6A 2G4, Canada
| | - Duncan D Cameron
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
- Institute for Sustainable Food, University of Sheffield, Sheffield, S10 2TN, UK
| | - Susan E Hartley
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Scott N Johnson
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, NSW, 2751, Australia
| | - Matthias C Rillig
- Institut für Biologie, Plant Ecology, Freie Universität Berlin, Berlin, D-14195, Germany
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Berlin, D-14195, Germany
| | - Alison E Bennett
- Department of Evolution, Ecology & Organismal Biology, The Ohio State University, Columbus, OH, 43210, USA
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Robbins C, Cruz Corella J, Aletti C, Seiler R, Mateus ID, Lee S, Masclaux FG, Sanders IR. Generation of unequal nuclear genotype proportions in Rhizophagus irregularis progeny causes allelic imbalance in gene transcription. New Phytol 2021; 231:1984-2001. [PMID: 34085297 PMCID: PMC8457141 DOI: 10.1111/nph.17530] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 05/25/2021] [Indexed: 05/05/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) form mutualisms with most plant species. The model AMF Rhizophagus irregularis is common in many ecosystems and naturally forms homokaryons and dikaryons. Quantitative variation in allele frequencies in clonally dikaryon offspring suggests they disproportionately inherit two distinct nuclear genotypes from their parent. This is interesting, because such progeny strongly and differentially affect plant growth. Neither the frequency and magnitude of this occurrence nor its effect on gene transcription are known. Using reduced representation genome sequencing, transcriptomics, and quantitative analysis tools, we show that progeny of homokaryons and dikaryons are qualitatively genetically identical to the parent. However, dikaryon progeny differ quantitatively due to unequal inheritance of nuclear genotypes. Allele frequencies of actively transcribed biallelic genes resembled the frequencies of the two nuclear genotypes. More biallelic genes showed transcription of both alleles than monoallelic transcription, but biallelic transcription was less likely with greater allelic divergence. Monoallelic transcription levels of biallelic genes were reduced compared with biallelic gene transcription, a finding consistent with genomic conflict. Given that genetic variation in R. irregularis is associated with plant growth, our results establish quantitative genetic variation as a future consideration when selecting AMF lines to improve plant production.
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Affiliation(s)
- Chanz Robbins
- Department of Ecology and EvolutionUniversity of LausanneBiophore BuildingLausanne1015Switzerland
| | - Joaquim Cruz Corella
- Department of Ecology and EvolutionUniversity of LausanneBiophore BuildingLausanne1015Switzerland
| | - Consolée Aletti
- Department of Ecology and EvolutionUniversity of LausanneBiophore BuildingLausanne1015Switzerland
| | - Réjane Seiler
- Department of Ecology and EvolutionUniversity of LausanneBiophore BuildingLausanne1015Switzerland
| | - Ivan D. Mateus
- Department of Ecology and EvolutionUniversity of LausanneBiophore BuildingLausanne1015Switzerland
| | - Soon‐Jae Lee
- Department of Ecology and EvolutionUniversity of LausanneBiophore BuildingLausanne1015Switzerland
| | - Frédéric G. Masclaux
- Group of Genetic MedicineGeneva University HospitalBuilding DGeneva1205Switzerland
| | - Ian R. Sanders
- Department of Ecology and EvolutionUniversity of LausanneBiophore BuildingLausanne1015Switzerland
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Chaturvedi A, Cruz Corella J, Robbins C, Loha A, Menin L, Gasilova N, Masclaux FG, Lee SJ, Sanders IR. The methylome of the model arbuscular mycorrhizal fungus, Rhizophagus irregularis, shares characteristics with early diverging fungi and Dikarya. Commun Biol 2021; 4:901. [PMID: 34294866 PMCID: PMC8298701 DOI: 10.1038/s42003-021-02414-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 07/01/2021] [Indexed: 12/16/2022] Open
Abstract
Early-diverging fungi (EDF) are distinct from Dikarya and other eukaryotes, exhibiting high N6-methyldeoxyadenine (6mA) contents, rather than 5-methylcytosine (5mC). As plants transitioned to land the EDF sub-phylum, arbuscular mycorrhizal fungi (AMF; Glomeromycotina) evolved a symbiotic lifestyle with 80% of plant species worldwide. Here we show that these fungi exhibit 5mC and 6mA methylation characteristics that jointly set them apart from other fungi. The model AMF, R. irregularis, evolved very high levels of 5mC and greatly reduced levels of 6mA. However, unlike the Dikarya, 6mA in AMF occurs at symmetrical ApT motifs in genes and is associated with their transcription. 6mA is heterogeneously distributed among nuclei in these coenocytic fungi suggesting functional differences among nuclei. While far fewer genes are regulated by 6mA in the AMF genome than in EDF, most strikingly, 6mA methylation has been specifically retained in genes implicated in components of phosphate regulation; the quintessential hallmark defining this globally important symbiosis. Anurag Chaturvedi et al. use long-read PacBio sequencing and LC-MS to profile 5mC and 6mA DNA methylation in the model arbuscular mycorrhizal fungus, Rhizophagus irregularis. Their results suggest that R. irregularis shows methylation profiles distinct from other early-diverging fungi, and Dikarya and provide further insight into how these fungi may have adapted to form symbiotic relationships with important plant species.
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Affiliation(s)
- Anurag Chaturvedi
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.,Environmental Genomics Group, School of Biosciences, The University of Birmingham, Birmingham, UK
| | - Joaquim Cruz Corella
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Chanz Robbins
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Anita Loha
- Department of Plant Molecular Biology, University of Lausanne, Lausanne, Switzerland
| | - Laure Menin
- Institute of Chemical Sciences and Engineering, Swiss Federal Institute of Technology Lausanne (EPFL), SSMI, Batochime, Lausanne, Switzerland
| | - Natalia Gasilova
- Institute of Chemical Sciences and Engineering, Swiss Federal Institute of Technology Lausanne (EPFL), SSMI, Batochime, Lausanne, Switzerland
| | - Frédéric G Masclaux
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Soon-Jae Lee
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Ian R Sanders
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.
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Kokkoris V, Chagnon PL, Yildirir G, Clarke K, Goh D, MacLean AM, Dettman J, Stefani F, Corradi N. Host identity influences nuclear dynamics in arbuscular mycorrhizal fungi. Curr Biol 2021; 31:1531-1538.e6. [PMID: 33545043 DOI: 10.1016/j.cub.2021.01.035] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/19/2020] [Accepted: 01/12/2021] [Indexed: 02/07/2023]
Abstract
The arbuscular mycorrhizal fungi (AMF) are involved in one of the most ecologically important symbioses on the planet, occurring within the roots of most land plants.1 Knowledge of even basic elements of AM fungal biology is still poor, with the discovery that AMF may in fact have a sexual life cycle being only very recently reported.2-5 AMF produce asexual spores that contain up to several thousand individual haploid nuclei6 of either largely uniform genotypes (AMF homokaryons) or nuclei originating from two parental genotypes2-5 (AMF dikaryons or heterokaryons). In contrast to the sexual dikaryons in the phyla Ascomycota and Basidiomycota,7,8 in which pairs of nuclei coexist in single hyphal compartments, AMF dikaryons carry several thousand nuclei in a coenocytic mycelium. Here, we set out to better understand the dynamics of this unique multinucleate condition by combining molecular analyses with advanced microscopy and modeling. Herein, we report that select AMF dikaryotic strains carry the distinct nucleotypes in equal proportions to one another, whereas others show an unequal distribution of parental nucleotypes. In both cases, the relative proportions within a given strain are inherently stable. Simulation models suggest that AMF dikaryons may be maintained through nuclear cooperation dynamics. Remarkably, we report that these nuclear ratios shift dramatically in response to plant host identity, revealing a previously unknown layer of genetic complexity and dynamism within the intimate interactions that occur between the partners of a prominent terrestrial symbiosis.
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Affiliation(s)
- Vasilis Kokkoris
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada; Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, ON K1A 0C6, Canada.
| | - Pierre-Luc Chagnon
- Institut de Recherche en Biologie Végétale, Université de Montréal, 4101 Sherbrooke Est, Montreal, QC H1X 2B2, Canada
| | - Gökalp Yildirir
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Kelsey Clarke
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada; Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, ON K1A 0C6, Canada
| | - Dane Goh
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Allyson M MacLean
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Jeremy Dettman
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, ON K1A 0C6, Canada
| | - Franck Stefani
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, ON K1A 0C6, Canada
| | - Nicolas Corradi
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
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Peña R, Robbins C, Corella JC, Thuita M, Masso C, Vanlauwe B, Signarbieux C, Rodriguez A, Sanders IR. Genetically Different Isolates of the Arbuscular Mycorrhizal Fungus Rhizophagus irregularis Induce Differential Responses to Stress in Cassava. Front Plant Sci 2020; 11:596929. [PMID: 33424891 PMCID: PMC7793890 DOI: 10.3389/fpls.2020.596929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 11/10/2020] [Indexed: 05/12/2023]
Abstract
Water scarcity negatively impacts global crop yields and climate change is expected to greatly increase the severity of future droughts. The use of arbuscular mycorrhizal fungi (AMF) can potentially mitigate the effects of water stress in plants. Cassava is a crop that feeds approximately 800 million people daily. Genetically different isolates of the AMF R. irregularis as well as their clonal progeny have both been shown to greatly alter cassava growth in field conditions. Given that cassava experiences seasonal drought in many of the regions in which it is cultivated, we evaluated whether intraspecific variation in R. irregularis differentially alters physiological responses of cassava to water stress. In a first experiment, conducted in field conditions in Western Kenya, cassava was inoculated with two genetically different R. irregularis isolates and their clonal progeny. All cassava plants exhibited physiological signs of stress during the dry period, but the largest differences occurred among plants inoculated with clonal progeny of each of the two parental fungal isolates. Because drought had not been experimentally manipulated in the field, we conducted a second experiment in the greenhouse where cassava was inoculated with two genetically different R. irregularis isolates and subjected to drought, followed by re-watering, to allow recovery. Physiological stress responses of cassava to drought differed significantly between plants inoculated with the two different fungi. However, plants that experienced higher drought stress also recovered at a faster rate following re-watering. We conclude that intraspecific genetic variability in AMF significantly influences cassava physiological responses during water stress. This highlights the potential of using naturally existing variation in AMF to improve cassava tolerance undergoing water stress. However, the fact that clonal progeny of an AMF isolate can differentially affect how cassava copes with natural drought stress in field conditions, highlights the necessity to understand additional factors, beyond genetic variation, which can account for such large differences in cassava responses to drought.
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Affiliation(s)
- Ricardo Peña
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Chanz Robbins
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Joaquim Cruz Corella
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Moses Thuita
- International Institute for Tropical Agriculture (IITA) Kenya, Nairobi, Kenya
| | - Cargele Masso
- International Institute for Tropical Agriculture (IITA) Cameroon, Yaoundé, Cameroon
| | - Bernard Vanlauwe
- International Institute for Tropical Agriculture (IITA) Kenya, Nairobi, Kenya
| | - Constant Signarbieux
- Laboratory of Ecological Systems (ECOS), Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Alia Rodriguez
- Department of Biology, National University of Colombia, Bogotá, Colombia
| | - Ian R. Sanders
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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Kokkoris V, Stefani F, Dalpé Y, Dettman J, Corradi N. Nuclear Dynamics in the Arbuscular Mycorrhizal Fungi. Trends Plant Sci 2020; 25:765-778. [PMID: 32534868 DOI: 10.1016/j.tplants.2020.05.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/30/2020] [Accepted: 05/20/2020] [Indexed: 05/09/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) are plant root symbionts that continuously carry thousands of nuclei in their spores and hyphae. This unique cellular biology raises fundamental questions regarding their nuclear dynamics. This review aims to address these by synthesizing current knowledge of nuclear content and behavior in these ubiquitous soil fungi. Overall, we find that that nuclear counts, as well as the nuclei shape and organization, vary drastically both within and among species in this group. By comparing these features with those of other fungi, we highlight unique aspects of the AMF nuclear biology that require further attention. The potential implications of the observed nuclear variability for the biology and evolution of these widespread plant symbionts are discussed.
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Affiliation(s)
- Vasilis Kokkoris
- Department of Biology, University of Ottawa, ON, Ottawa, K1N 6N5, Canada; Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, ON, Ottawa, K1A 0C5, Canada.
| | - Franck Stefani
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, ON, Ottawa, K1A 0C5, Canada
| | - Yolande Dalpé
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, ON, Ottawa, K1A 0C5, Canada
| | - Jeremy Dettman
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, ON, Ottawa, K1A 0C5, Canada
| | - Nicolas Corradi
- Department of Biology, University of Ottawa, ON, Ottawa, K1N 6N5, Canada.
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