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Quo vadis: signaling molecules and small secreted proteins from mycorrhizal fungi at the early stage of mycorrhiza formation. Symbiosis 2021. [DOI: 10.1007/s13199-021-00793-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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2
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Garcia K, Guerrero-Galán C, Frank HER, Haider MZ, Delteil A, Conéjéro G, Lambilliotte R, Fizames C, Sentenac H, Zimmermann SD. Fungal Shaker-like channels beyond cellular K+ homeostasis: A role in ectomycorrhizal symbiosis between Hebeloma cylindrosporum and Pinus pinaster. PLoS One 2020; 15:e0242739. [PMID: 33216794 PMCID: PMC7678990 DOI: 10.1371/journal.pone.0242739] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 11/07/2020] [Indexed: 01/04/2023] Open
Abstract
Potassium (K+) acquisition, translocation and cellular homeostasis are mediated by various membrane transport systems in all organisms. We identified and described an ion channel in the ectomycorrhizal fungus Hebeloma cylindrosporum (HcSKC) that harbors features of animal voltage-dependent Shaker-like K+ channels, and investigated its role in both free-living hyphae and symbiotic conditions. RNAi lines affected in the expression of HcSKC were produced and used for in vitro mycorrhizal assays with the maritime pine as host plant, under standard or low K+ conditions. The adaptation of H. cylindrosporum to the downregulation of HcSKC was analyzed by qRT-PCR analyses for other K+-related transport proteins: the transporters HcTrk1, HcTrk2, and HcHAK, and the ion channels HcTOK1, HcTOK2.1, and HcTOK2.2. Downregulated HcSKC transformants displayed greater K+ contents at standard K+ only. In such conditions, plants inoculated with these transgenic lines were impaired in K+ nutrition. Taken together, these results support the hypothesis that the reduced expression of HcSKC modifies the pool of fungal K+ available for the plant and/or affects its symbiotic transfer to the roots. Our study reveals that the maintenance of K+ transport in H. cylindrosporum, through the regulation of HcSKC expression, is required for the K+ nutrition of the host plant.
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Affiliation(s)
- Kevin Garcia
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, California, United States of America
| | | | - Hannah E. R. Frank
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, California, United States of America
| | | | - Amandine Delteil
- BPMP, Université de Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Geneviève Conéjéro
- BPMP, Université de Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
- Plateforme Histocytologie et Imagerie Cellulaire Végétale, INRA-CIRAD Montpellier, France
| | - Raphaël Lambilliotte
- BPMP, Université de Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Cécile Fizames
- BPMP, Université de Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Hervé Sentenac
- BPMP, Université de Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
| | - Sabine D. Zimmermann
- BPMP, Université de Montpellier, CNRS, INRAE, Institut Agro, Montpellier, France
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Liu J, Liu X, Zhang Q, Li S, Sun Y, Lu W, Ma C. Response of alfalfa growth to arbuscular mycorrhizal fungi and phosphate-solubilizing bacteria under different phosphorus application levels. AMB Express 2020; 10:200. [PMID: 33141419 PMCID: PMC7609620 DOI: 10.1186/s13568-020-01137-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/21/2020] [Indexed: 12/26/2022] Open
Abstract
Alfalfa (Medicago sativa L.) is an important forage legume in farming and animal husbandry systems. This study assessed the effects of arbuscular mycorrhizal fungi (AMF) and phosphate-solubilizing bacteria (PSB) on alfalfa growth under different phosphorus application levels. In this experiment, a complete randomized block design was used. The following four bacterial applications were used: inoculation of Funneliformis mosseae (Fm), inoculation of Bacillus megaterium (Bm), inoculation of mixed species (Fm × Bm) and noninoculation treatment (CK). Phosphorus (P) treatment was applied at the following four levels: 0 mg kg−1 (P0), 50 mg kg−1 (P1), 100 mg kg−1 (P2) and 150 mg P kg−1 (P3). The results showed that with the increase in phosphorus application, each index increased first and then decreased. The J2 treatment was significantly greater than the J0 treatment (P < 0.05) under the same bacterial treatment. In each cropping period the difference in each index to alfalfa was extremely significant under J, P treatment and J × P interactive treatment (P < 0.01). The indexes were compared by membership function. The priority order was as follows: J3P2 > J1P2 > J3P1 treatment. Therefore, when phosphorus was applied at 100 mg kg−1, the mixed inoculation of Fm × Bm was optimal, benefitting mycorrhiza growth and the production performance of alfalfa.
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Sato T, Hachiya S, Inamura N, Ezawa T, Cheng W, Tawaraya K. Secretion of acid phosphatase from extraradical hyphae of the arbuscular mycorrhizal fungus Rhizophagus clarus is regulated in response to phosphate availability. MYCORRHIZA 2019; 29:599-605. [PMID: 31745622 DOI: 10.1007/s00572-019-00923-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/15/2019] [Indexed: 06/10/2023]
Abstract
Arbuscular mycorrhizal (AM) fungi increase phosphate (P) uptake by plants. Organic phosphate comprises 30-80% of total P in most agricultural soils. Some plants can utilize organic phosphate by secreting acid phosphatase (ACP) from their roots, especially under low P conditions. Although secretion of ACP from extraradical hyphae of AM fungi has been reported, the specific factors that affect the secretion of ACP are unknown. The objective of the present study was to investigate whether secretion of ACP from extraradical hyphae is induced by low P conditions. First, specimens of Allium fistulosum were either inoculated with the AM fungus Rhizophagus clarus strain CK001 or remained uninoculated and were grown in soil with 0.5 g P2O5 kg-1 soil or without P fertilization using two-compartment pots. Soil solution was collected using mullite ceramic tubes 45 days after sowing. The soil solution was analyzed for ACP activity by using p-nitrophenylphosphate. Second, Ri T-DNA transformed roots (i.e., hairy roots) of Linum usitatissimum inoculated with R. clarus were grown on solid minimal media with two P levels applied (3 and 30 μM P) using two-compartment Petri dishes under in vitro conditions. Hyphal exudates, extraradical hyphae, and hairy roots were collected and analyzed for ACP activity. ACP activity in the soil solution of the hyphal compartment in the A. fistulosum inoculation treatment was higher without P fertilization than with P fertilization. AM colonization also was higher without P fertilization than with P fertilization. In the in vitro two-compartment culture, ACP activity of hyphal exudates and extraradical hyphae were higher under the 3-μM treatment than under the 30-μM treatment. These findings suggest that the secretion of ACP from the extraradical hyphae of R. clarus into the hyphosphere is promoted under low P conditions.
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Affiliation(s)
- Takumi Sato
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997-8555, Japan
| | - Shihomi Hachiya
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997-8555, Japan
| | - Nozomi Inamura
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997-8555, Japan
| | - Tatsuhiro Ezawa
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Weiguo Cheng
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997-8555, Japan
| | - Keitaro Tawaraya
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997-8555, Japan.
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Phosphorus Mobilizing Enzymes of Alnus-Associated Ectomycorrhizal Fungi in an Alaskan Boreal Floodplain. FORESTS 2019. [DOI: 10.3390/f10070554] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Because of its high phosphorus (P) demands, it is likely that the abundance, distribution, and N-fixing capacity of Alnus in boreal forests are tightly coupled with P availability and the mobilization and uptake of soil P via ectomycorrhizal fungi (EMF). We examined whether Alnus shifts EMF communities in coordination with increasingly more complex organic P forms across a 200-year-old successional sequence along the Tanana River in interior Alaska. Root-tip activities of acid phosphatase, phosphodiesterase, and phytase of A. tenuifolia-associated EMF were positively intercorrelated but did not change in a predictable manner across the shrub, to hardwood to coniferous forest successional sequence. Approximately half of all Alnus roots were colonized by Alnicola and Tomentella taxa, and ordination analysis indicated that the EMF community on Alnus is a relatively distinct, host-specific group. Despite differences in the activities of the two Alnus dominants to mobilize acid phosphatase and phosphodiesterase, the root-tip activities of P-mobilizing enzymes of the Alnus-EMF community were not dramatically different from other co-occurring boreal plant hosts. This suggests that if Alnus has a greater influence on P cycling than other plant functional types, additional factors influencing P mobilization and uptake at the root and/or whole-plant level must be involved.
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Guerrero-Galán C, Garcia K, Houdinet G, Zimmermann SD. HcTOK1 participates in the maintenance of K + homeostasis in the ectomycorrhizal fungus Hebeloma cylindrosporum, which is essential for the symbiotic K + nutrition of Pinus pinaster. PLANT SIGNALING & BEHAVIOR 2018; 13:e1480845. [PMID: 29939816 PMCID: PMC6110361 DOI: 10.1080/15592324.2018.1480845] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 05/16/2018] [Indexed: 05/23/2023]
Abstract
Most land plants rely on root symbioses to complement or improve their mineral nutrition. Recent researches have put forward that mycorrhizal fungi efficiently absorb and transfer potassium (K+) from the soil to host plant roots, but the molecular mechanisms involved are not completely elucidated yet. We have recently revealed that K+ is likely released from the fungal Hartig net to the plant by TOK channels in the ectomycorrhizal model Hebeloma cylindrosporum - Pinus pinaster. H. cylindrosporum harbours three TOK members. Herein, we report that one of them, HcTOK1, has similar features than the yeast ScTOK1. Moreover, we propose a role for this channel in the transport of K+ from the medium to ectomycorrhizal roots under K+ starvation.
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Affiliation(s)
- C. Guerrero-Galán
- BPMP, Univ Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
| | - K. Garcia
- Biology and Microbiology Department, South Dakota State University, Brookings, South Dakota USA
| | - G. Houdinet
- BPMP, Univ Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
| | - S. D. Zimmermann
- BPMP, Univ Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
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Guerrero-Galán C, Delteil A, Garcia K, Houdinet G, Conéjéro G, Gaillard I, Sentenac H, Zimmermann SD. Plant potassium nutrition in ectomycorrhizal symbiosis: properties and roles of the three fungal TOK potassium channels in Hebeloma cylindrosporum. Environ Microbiol 2018; 20:1873-1887. [PMID: 29614209 DOI: 10.1111/1462-2920.14122] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/11/2018] [Accepted: 03/27/2018] [Indexed: 12/16/2022]
Abstract
Ectomycorrhizal fungi play an essential role in the ecology of boreal and temperate forests through the improvement of tree mineral nutrition. Potassium (K+ ) is an essential nutrient for plants and is needed in high amounts. We recently demonstrated that the ectomycorrhizal fungus Hebeloma cylindrosporum improves the K+ nutrition of Pinus pinaster under shortage conditions. Part of the transport systems involved in K+ uptake by the fungus has been deciphered, while the molecular players responsible for the transfer of this cation towards the plant remain totally unknown. Analysis of the genome of H. cylindrosporum revealed the presence of three putative tandem-pore outward-rectifying K+ (TOK) channels that could contribute to this transfer. Here, we report the functional characterization of these three channels through two-electrode voltage-clamp experiments in oocytes and yeast complementation assays. The expression pattern and physiological role of these channels were analysed in symbiotic interaction with P. pinaster. Pine seedlings colonized by fungal transformants overexpressing two of them displayed a larger accumulation of K+ in shoots. This study revealed that TOK channels have distinctive properties and functions in axenic and symbiotic conditions and suggested that HcTOK2.2 is implicated in the symbiotic transfer of K+ from the fungus towards the plant.
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Affiliation(s)
- Carmen Guerrero-Galán
- BPMP, Université de Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
| | - Amandine Delteil
- BPMP, Université de Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
| | - Kevin Garcia
- BPMP, Université de Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France.,Biology and Microbiology Department, South Dakota State University, Brookings, SD 57007, USA
| | - Gabriella Houdinet
- BPMP, Université de Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
| | - Geneviève Conéjéro
- BPMP, Université de Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France.,Plateforme Histocytologie et Imagerie Cellulaire Végétale, INRA-CIRAD, Montpellier, France
| | - Isabelle Gaillard
- BPMP, Université de Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
| | - Hervé Sentenac
- BPMP, Université de Montpellier, CNRS, INRA, Montpellier SupAgro, Montpellier, France
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Torres-Aquino M, Becquer A, Le Guernevé C, Louche J, Amenc LK, Staunton S, Quiquampoix H, Plassard C. The host plant Pinus pinaster exerts specific effects on phosphate efflux and polyphosphate metabolism of the ectomycorrhizal fungus Hebeloma cylindrosporum: a radiotracer, cytological staining and 31 P NMR spectroscopy study. PLANT, CELL & ENVIRONMENT 2017; 40:190-202. [PMID: 27743400 DOI: 10.1111/pce.12847] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 10/06/2016] [Accepted: 10/07/2016] [Indexed: 05/23/2023]
Abstract
Ectomycorrhizal (ECM) association can improve plant phosphorus (P) nutrition. Polyphosphates (polyP) synthesized in distant fungal cells after P uptake may contribute to P supply from the fungus to the host plant if they are hydrolyzed to phosphate in ECM roots then transferred to the host plant when required. In this study, we addressed this hypothesis for the ECM fungus Hebeloma cylindrosporum grown in vitro and incubated without plant or with host (Pinus pinaster) and non-host (Zea mays) plants, using an experimental system simulating the symbiotic interface. We used 32 P labelling to quantify P accumulation and P efflux and in vivo and in vitro nuclear magnetic resonance (NMR) spectroscopy and cytological staining to follow the fate of fungal polyP. Phosphate supply triggered a massive P accumulation as newly synthesized long-chain polyP in H. cylindrosporum if previously grown under P-deficient conditions. P efflux from H. cylindrosporum towards the roots was stimulated by both host and non-host plants. However, the host plant enhanced 32 P release compared with the non-host plant and specifically increased the proportion of short-chain polyP in the interacting mycelia. These results support the existence of specific host plant effects on fungal P metabolism able to provide P in the apoplast of ectomycorrhizal roots.
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Affiliation(s)
- Margarita Torres-Aquino
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
- Colegio de Postgraduados, Campus San Luis Potosí, Agustín de Iturbide N 73, CP 78600, San Luis Potosí, Mexico
| | - Adeline Becquer
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Christine Le Guernevé
- INRA, UMR SPO (1083) Sciences pour l'Oenologie, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Julien Louche
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Laurie K Amenc
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Siobhan Staunton
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Hervé Quiquampoix
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Claude Plassard
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
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Becquer A, Trap J, Irshad U, Ali MA, Claude P. From soil to plant, the journey of P through trophic relationships and ectomycorrhizal association. FRONTIERS IN PLANT SCIENCE 2014; 5:548. [PMID: 25360140 PMCID: PMC4197793 DOI: 10.3389/fpls.2014.00548] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 09/25/2014] [Indexed: 05/19/2023]
Abstract
Phosphorus (P) is essential for plant growth and productivity. It is one of the most limiting macronutrients in soil because it is mainly present as unavailable, bound P whereas plants can only use unbound, inorganic phosphate (Pi), which is found in very low concentrations in soil solution. Some ectomycorrhizal fungi are able to release organic compounds (organic anions or phosphatases) to mobilize unavailable P. Recent studies suggest that bacteria play a major role in the mineralization of nutrients such as P through trophic relationships as they can produce specific phosphatases such as phytases to degrade phytate, the main form of soil organic P. Bacteria are also more effective than other microorganisms or plants at immobilizing free Pi. Therefore, bacterial grazing by grazers, such as nematodes, could release Pi locked in bacterial biomass. Free Pi may be taken up by ectomycorrhizal fungus by specific phosphate transporters and transferred to the plant by mechanisms that have not yet been identified. This mini-review aims to follow the phosphate pathway to understand the ecological and molecular mechanisms responsible for transfer of phosphate from the soil to the plant, to improve plant P nutrition.
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Affiliation(s)
- Adeline Becquer
- UMR Eco&Sols, Institut National de la Recherche AgronomiqueMontpellier, France
| | - Jean Trap
- UMR Eco&Sols, Institut de Recherche pour le DéveloppementMontpellier, France
| | - Usman Irshad
- Department of Environmental Sciences, COMSATS Institute of Information TechnologyAbbottabad, Pakistan
| | - Muhammad A. Ali
- Department of Soil Science, Bahauddin Zakariya UniversityMultan, Pakistan
| | - Plassard Claude
- UMR Eco&Sols, Institut National de la Recherche AgronomiqueMontpellier, France
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Garcia K, Delteil A, Conéjéro G, Becquer A, Plassard C, Sentenac H, Zimmermann S. Potassium nutrition of ectomycorrhizal Pinus pinaster: overexpression of the Hebeloma cylindrosporum HcTrk1 transporter affects the translocation of both K(+) and phosphorus in the host plant. THE NEW PHYTOLOGIST 2014; 201:951-960. [PMID: 24279702 DOI: 10.1111/nph.12603] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/16/2013] [Indexed: 05/07/2023]
Abstract
Mycorrhizal associations are known to improve the hydro-mineral nutrition of their host plants. However, the importance of mycorrhizal symbiosis for plant potassium nutrition has so far been poorly studied. We therefore investigated the impact of the ectomycorrhizal fungus Hebeloma cylindrosporum on the potassium nutrition of Pinus pinaster and examined the involvement of the fungal potassium transporter HcTrk1. HcTrk1 transcripts and proteins were localized in ectomycorrhizas using in situ hybridization and EGFP translational fusion constructs. Importantly, an overexpression strategy was performed on a H. cylindrosporum endogenous gene in order to dissect the role of this transporter. The potassium nutrition of mycorrhizal pine plants was significantly improved under potassium-limiting conditions. Fungal strains overexpressing HcTrk1 reduced the translocation of potassium and phosphorus from the roots to the shoots of inoculated plants in mycorrhizal experiments. Furthermore, expression of HcTrk1 and the phosphate transporter HcPT1.1 were reciprocally linked to the external inorganic phosphate and potassium availability. The development of these approaches provides a deeper insight into the role of ectomycorrhizal symbiosis on host plant K(+) nutrition and in particular, the K(+) transporter HcTrk1. The work augments our knowledge of the link between potassium and phosphorus nutrition via the mycorrhizal pathway.
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Affiliation(s)
- Kevin Garcia
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Amandine Delteil
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Geneviève Conéjéro
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
- Plateforme Histocytologie et Imagerie Cellulaire Végétale, INRA-CIRAD, 34398, Montpellier, France
| | - Adeline Becquer
- INRA, UMR 1222 Eco&Sols, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Claude Plassard
- INRA, UMR 1222 Eco&Sols, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Hervé Sentenac
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Sabine Zimmermann
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
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