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Maria Harrison
 &emdash;  William H. Crocker Professor

Maria Harrison
Office/Lab: 405/406
  • Adjunct Professor
  • Section of Plant Pathology & Plant-Microbe Biology
  • School of Integrative Plant Science
  • Cornell University
Graduate Fields: Plant Pathology & Plant-Microbe Biology; Plant Biology


  • Exocytosis for endosymbiosis: membrane trafficking pathways for development of symbiotic membrane compartments 2017

    MJ Harrison, S Ivanov
    Current Opinion in Plant Biology 38,  101-108
    Full text...
  • Arbuscular mycorrhiza‐specific enzymes FatM and RAM2 fine‐tune lipid biosynthesis to promote development of arbuscular mycorrhiza 2017

    A Bravo, M Brands, V Wewer, P Dörmann, MJ Harrison
    New Phytologist 214 (4),  1631-1645
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  • A transcriptional program for arbuscule degeneration during AM symbiosis is regulated by MYB1 2017

    DS Floss, SK Gomez, HJ Park, AM MacLean, LM Müller, KK Bhattarai, V Lévesque-Tremblay, IE Maldonado-Mendoza, MJ Harrison
    Current Biology 27 (8),  1206-1212
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  • A comprehensive draft genome sequence for lupin (Lupinus angustifolius), an emerging health food: insights into plant-microbe interactions and legume evolution. 2017

    Hane JK, Ming Y, Kamphuis LG, Nelson MN, Garg G, Atkins CA, Bayer PE, Bravo A, Bringans S, Cannon S, Edwards D, Foley R, Gao LL, Harrison MJ, Huang W, Hurgobin B, Li S, Liu CW, McGrath A, Morahan G, Murray J, Weller J, Jian J, Singh KB.
    Plant biotechnology journal 15 (3),  318-330
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  • A CCaMK-CYCLOPS-DELLA complex activates transcription of RAM1 to regulate arbuscule branching 2016

    P Pimprikar, S Carbonnel, M Paries, K Katzer, V Klingl, MJ Bohmer, L Karl, DS Floss, MJ Harrison, M Parniske, C Gutjahr
    Current Biology 26 (8),  987-998
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  • DELLA proteins regulate expression of a subset of AM symbiosis-induced genes in Medicago truncatula 2016

    DS Floss, V Lévesque-Tremblay, HJ Park, MJ Harrison
    Plant signaling & behavior 11(4),  e1162369
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  • Genes conserved for arbuscular mycorrhizal symbiosis identified through phylogenomics 2016

    A Bravo, T York, N Pumplin, LA Mueller, MJ Harrison
    Nature Plants 2,  15208
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  • Identification of Genes that Regulate Phosphate Acquisition and Plant Performance during Arbuscular Mycorrhizal Symbiosis in Medicago truncatula and Brachypodium distachyon 2015

    Maria J. Harrison and Matthew E. Hudson
    SciTech Connect Report Number: DOE-BTI--64628-1 6072546472
    Full text...
  • Hyphal branching during arbuscule development requires RAM1 2015

    HJ Park, DS Floss, V Levesque-Tremblay, A Bravo, MJ Harrison
    Plant Physiology 169,  2774-2788
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  • How grow-and-switch gravitropism generates root coiling and root waving growth responses in Medicago truncatula 2015

    TH Tan, JL Silverberg, DS Floss, MJ Harrison, CL Henley, I Cohen
    PNAS 112 (42),  12938-12943
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  • EXO70I is essential for development of a sub-domain of the periarbuscular membrane during arbuscular mycorrhizal symbiosis. 2015

    Zhang X, Pumplin N, Ivanov S, Harrison M J.
    Current Biology 25,  2189-2195
    Full text...
  • Suppression of Arbuscule Degeneration in Medicago truncatula phosphate transporter4 Mutants Is Dependent on the Ammonium Transporter 2 Family Protein AMT2;3 2015

    Breuillin-Sessoms, F., Floss, D.S., Gomez, K.S., Pumplin, N., Ding, Y., Levesque-Tremblay, V., Noar, R.D., Daniels, D.A., Bravo, A., Eaglesham, J.B., Benedito, V.A., Udvardi, M.K., and Harrison, M.J.
    The Plant Cell, tpc. 114,  131144
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  • A set of fluorescent protein-based markers expressed from constitutive and arbuscular mycorrhiza-inducible promoters to label organelles, membranes and cytoskeletal elements in Medicago truncatula. Plant J. ;80(6):1151-63. doi: 10.1111/tpj.12706 2014

    Ivanov S, Harrison MJ.
    Plant J. 80(6):1151-63,  doi: 10.1111/tpj.12706
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  • DELLA proteins regulate arbuscule formation in arbuscular mycorrhizal symbiosis 2013

    Floss, D.S., Levy, J.G., Levesque-Tremblay, V., Pumplin, N., and Harrison, M.J.
    P. Natl. Acad. Sci., U S A 110,  E5025-5034
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  • Gene silencing in Medicago truncatula roots using RNAi. Methods in Molecular Biology (Clifton, N.J.), 1069, 163-177 2013

    Floss, D.S., Schmitz, A.M., Starker, C.G., Gantt, J.S., and Harrison, M.J.
    Methods in Molecular Biology (Clifton, N.J.) 1069,  163-177
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  • Using membrane transporters to improve crops for sustainable food production 2013

    Schroeder, J.I., Delhaize, E., Frommer, W.B., Guerinot, M.L., Harrison, M.J., Herrera-Estrella, L., Horie, T., Kochian, L.V., Munns, R., Nishizawa, N.K., Tsay, Y.F., and Sanders, D .
    Nature 497,  60-66
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  • Spatio-Temporal Expression Patterns of Arabidopsis thaliana and Medicago truncatula Defensin-Like Genes 2013

    Tesfaye, M., Silverstein, K.A.T., Nallu, S., Wang, L., Botanga, C.J., Gomez, S.K., Costa, L.M., Harrison, M.J., Samac, D.A., Glazebrook, J., Katagiri, F., Gutierrez-Marcos, J.F., and VandenBosch, K.A.
    PLoS ONE 8,  e58992
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  • The half-size ABC transporters STR1 and STR2 are indispensable for mycorrhizal arbuscule formation in rice 2012

    Gutjahr, C., Radovanovic, D., Geoffroy, J., Zhang, Q., Siegler, H., Chiapello, M., Casieri, L., An, K., An, G., Guiderdoni, E., Kumar, C.S., Sundaresan, V., Harrison, M.J., and Paszkowski, U.
    The Plant Journal , 906-920,  906-920
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  • Cellular programs for arbuscular mycorrhizal symbiosis 2012

    Harrison, M.J.
    Curr. Opin. Plant Biol. 15,  691-698
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  • Diversity of morphology and function in arbuscular mycorrhizal symbioses in Brachypodium distachyon 2012

    Hong , J.J., Park, Y.S., Bravo, A., Bhattarai, K.K., Daniels, D.A., and Harrison, M.J.
    Planta 236,  851-865
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  • Transgenic expression of phytase and acid phosphatase genes in alfalfa (Medicago sativa) leads to improved phosphate uptake in natural soils 2012

    Ma, X.F., Tudor, S., Butler, T., Ge, Y.X., Xi, Y.J., Bouton, J., Harrison, M., and Wang, Z.Y.
    Molecular Breeding 30,  377-391
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  • Polar localization of a symbiosis-specific phosphate transporter is mediated by a transient reorientation of secretion 2012

    Pumplin, N., Zhang, X., Noar, R.D., and Harrison, M.J.
    P. Natl. Acad. Sci. U S A 109,  E665-672
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  • Arsenate induces the expression of fungal genes involved in As transport in arbuscular mycorrhiza. Fungal Biol., 115, 1197-1209 2011

    Gonzalez-Chavez, M.C., P., O.-L.M., Carrillo-Gonzalez, R., Lopez-Meyer, M., Xoconostle-Cazares, B., Gomez, S.K., Harrison, M.J., Figueroa-Lopez, A.M., and Maldonado-Mendoza, I.E.
    Fungal Biol. 115,  1197-1209
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  • 3D imaging and mechanical modeling of helical buckling in Medicago truncatula plant roots 2012

    Silverberg, J.L., Noar, R.D., Packer, M.S., Harrison, M.J., Henley, C.L., Cohen, I., and Gerbode, S.J.
    P. Natl. Acad. Sci. U S A 109,  16794-16799
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  • Medicago truncatula mtpt4 mutants reveal a role for nitrogen in the regulation of arbuscule degeneration in arbuscular mycorrhizal symbiosis 2011

    Javot, H., Penmetsa, R.V., Breuillin, F., Bhattarai, K.K., Noar, R.D., Gomez, S.K., Zhang, Q., Cook, D.R., and Harrison, M.J.
    Plant J 68,  954-965
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  • Phosphate transporters in arbuscular mycorrhizal symbiosis. In Arbuscular Mycorrhizas: Physiology and Function 2010

    Harrison, M.J., Pumplin, N., Breuillin, F.J., Noar, R.D., and Park, H.-J.
    (Koltai, H. and Kapulnik, Y. eds). 0: New York, Springer
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  • Genomic inventory and transcriptional analysis of Medicago truncatula transporters 2010

    Benedito, V.A., Li, H.Q., Dai, X.B., Wandrey, M., He, J., Kaundal, R., Torres-Jerez, I., Gomez, S.K., Harrison, M.J., Tang, Y.H., Zhao, P.X., and Udvardi, M.K.
    Plant Physiology 152,  1716-1730
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  • Medicago truncatula Vapyrin is a novel protein required for arbuscular mycorrhizal symbiosis 2010

    Pumplin, N., Mondo, S.J., Topp, S., Starker, C.G., Gantt, J.S. and Harrison, M.J.
    Plant J. 61,  482-494
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  • Genetic variation for root architecture, nutrient uptake and mycorrhizal colonisation in Medicago truncatula accessions 2010

    Schultz, C.J., Kochian, L.V., and Harrison, M.J.
    Plant and Soil 336,  113-128
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  • Two Medicago truncatula half-ABC transporters are essential for arbuscule development in arbuscular mycorrhizal symbiosis 2010

    Zhang, Q., Blaylock, L.A., and Harrison, M.J.
    Plant Cell 22,  1483-1497
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  • Live-cell imaging reveals periarbuscular membrane domains and organelle location in Medicago truncatula roots during arbuscular mycorrhizal symbiosis 2009

    Pumplin, N., and Harrison, M.J.
    Plant Physiology 151,  809-81
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  • Reprogramming plant cells for endosymbiosis 2009

    Oldroyd, G.E.D., Harrison, M.J., and Paszkowski, U.
    Science , 753-754,  753-754
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  • Medicago truncatula and Glomus intraradices gene expression in cortical cells harboring arbuscules in the arbuscular mycorrhizal symbiosis 2009

    Gomez, S.K., Javot, H., Deewatthanawong, P., Torres-Jerez, I., Tang, Y., Blancaflor, E.B., Udvardi, M.K., and Harrison, M.J.
    BMC Plant Biol. 9,  10
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  • Laser microdissection and its application to analyze gene expression in arbuscular mycorrhizal symbiosis 2009

    Gomez, S.K., and Harrison, M.J.
    Pest Management Science 65,  504-511
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  • Novel plant and fungal AGP-like proteins in the Medicago truncatula-Glomus intraradices arbuscular mycorrhizal symbiosis 2008

    Schultz, C.J., and Harrison, M.J.
    Mycorrhiza 18,  403-412
    Full text...
  • The Medicago truncatula ortholog of Arabidopsis EIN2, sickle, is a negative regulator of symbiotic and pathogenic microbial associations 2008

    Penmetsa, R.V., Uribe, P., Anderson, J., Lichtenzveig, J., Gish, J.C., Nam, Y.W., Engstrom, E., Xu, K., Sckisel, G., Pereira, M., Baek, J.M., Lopez-Meyer, M., Long, S.R., Harrison, M.J., Singh, K.B., Kiss, G.B., and Cook, D.R.
    Plant J. 55,  580-595
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  • Closely related members of the Medicago truncatula PHT1 phosphate transporter gene family encode phosphate transporters with distinct biochemical activities 2008

    Liu, J.Y., Versaw, W.K., Pumplin, N., Gomez, S.K., Blaylock, L.A., and Harrison, M.J.
    Journal of Biological Chemistry 283,  24673-24681
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  • A Medicago truncatula phosphate transporter indispensable for the arbuscular mycorrhizal symbiosis 2007

    Javot, H., Penmetsa, R.V., Terzaghi, N., Cook, D.R., and Harrison, M.J.
    P. Natl. Acad. Sci. U S A 104,  1720-1725
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  • Signaling in the Arbuscular Mycorrhizal Symbiosis 2005

    Harrison, M.J.
    Annual Review of Microbiology 59,  19-42
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  • Transcript Profiling Coupled with Spatial Expression Analyses Reveals Genes Involved in Distinct Developmental Stages of an Arbuscular Mycorrhizal Symbiosis 2003

    Liu, J. Y., Blaylock, L.A., Endre, G., Cho, J., Town, C.D., VandenBosch, K.A., and Harrison, M.J.
    Plant Cell 15,  2106-2123
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  • A phosphate transporter from Medicago truncatula involved in the acquisition of phosphate released by arbuscular mycorrhizal fungi 2002

    Harrison, M. J., Dewbre, G.R., and Liu, J.
    Plant Cell 14,  2413-2429
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  • A chloroplast phosphate transporter, PHT2;1, influences allocation of phosphate within the plant and phosphate-starvation responses 2002

    Versaw, W.K., and Harrison, M.J.
    Plant Cell 14,  1751-1766
    Full text...

Intern Projects

Molecular analyses of arbuscular mycorrhizal (AM) symbiosis

Phosphorus is a critical macronutrient for proper plant growth. While phosphorus deficiencies can be improved by the application of phosphate fertilizers, it is costly, both to the farmer and to the environment. Furthermore, the crops only take up a small percentage of the applied fertilizer; the remainder is either immobilized in the soil, or carried into ground water and rivers, often resulting in pollution.

Interns in the  Harrison lab investigate two aspects of plant phosphorus nutrition. The first aspect seeks to understand the basis for the symbiotic relationships between vascular flowering plants and arbuscular mycorrhizal (AM) fungi. The fungi colonize root cells, gaining access to carbon supplied by the plant, while at the same time mobilizing mineral nutrients from the soil, including phosphorus, to be used by the plant. For this work, the lab uses the model legume, Medicago truncatula and the fungus Glomus versiforme. The Harrison lab also studies how plants find and take up phosphorus from the soil when they do not have these symbiotic relationships with fungi. This work toward understanding the mechanisms of perception and acquisition of phosphorus by plants may eventually lead to a more effective usage of fertilizers.

Click the links to return to the Intern FacultyInternship Program,  Apply for an Internship pages on the BTI website



    • Technology Area: Yield Inputs
    • Title: Plants with increased phosphorous uptake
    • US Patent/Application(s): 7,417,181
    • Technology Area: Yield Inputs
    • Title: Plant phytase genes and methods of use
    • US Patent/Application(s): 7,557,265
    • Publication: Planta 2005
    • Technology Area: Enabling Technology – Gene Expression
    • Title: MtHP promoter element
    • US Patent/Application(s): 7,056,743
    • Publication: Mol Breed 2005
    • Technology Area: Enabling Technology – Gene Expression
    • Title: Root-specific phosphate transporter promoters
    • US Patent/Application(s): 12/257,276
    • Publication: Plant Bio 2006

Research Utilization

The Arbuscular Mycorrhizal Symbiosis

Except for members of the Brassica family, all crop species of agronomic significance have the capacity to form symbioses with arbuscular mycorrhizal (AM) fungi. These beneficial associations have a profound effect on plant phosphorus nutrition and consequently impact plant growth and health. Phosphorous (P) is one of the mineral nutrients essential for plant growth but is relatively difficult for plants to obtain. Although the total P content of soils may be high, P exists in inorganic and organic complexes that are unavailable to plants. Consequently, after nitrogen, P is the mineral nutrient that is most frequently limiting for plant growth.

In many agricultural soils, P availability limits plant growth, a problem which is addressed by the input of phosphate (Pi) fertilizers. This has both economic and environmental costs as the immediate recovery of Pi by plants is low, and excess fertilizer run-off contributes to the pollution of aquatic ecosystems. Furthermore, rock Pi, the raw material for superphosphate fertilizers, is a non-renewable resource and reserves are being depleted. Beyond food crops, the future use of marginally fertile lands for the production of biofuel crops will further increase the need for sustainable fertilization strategies. Consequently, it is essential that we understand and deploy partnerships such as the AM symbiosis to maximize agricultural productivity in an economically and environmentally sustainable manner.

To ensure that crop plants contain the optimal set of alleles for a maximally functioning AM symbiosis, it is necessary first to understand which genes control the AM symbiosis and the molecular basis of their function. The long-term goals of Dr. Harrison’s research program are to understand the molecular mechanisms underlying development and regulation of the AM symbiosis, and symbiotic phosphate (Pi) transport. Medicago truncatula and Brachypodium distachyon are used as model plant hosts, along with 3 AM fungi, Glomus versiforme, G. intraradices and Gigaspora gigantea. Using these systems, the lab has taken an integrated approach to analyzing the AM symbiosis, and several genes that that are essential for regulation of the symbiosis and symbiotic Pi transport have been identified.

Collaboration and Consulting Opportunities

  • Improving nutrient acquisition by modulating the Arbuscular Mycorrhizal symbiosis

Collaborations and Consulting

In the News

Research Overview

Most vascular flowering plants are able to form symbiotic associations with arbuscular mycorrhizal (AM) fungi. These associations, named ‘arbuscular mycorrhizas’, develop in the roots, where the fungus colonizes the cortex to access carbon supplied by the plant. The fungal contribution to the symbiosis includes the transfer of mineral nutrients, particularly phosphorus, from the soil to the plant. In many soils, phosphate exists at levels that are limiting for plant growth. Consequently, additional phosphate supplied via AM fungi can have a significant impact on plant development, and this symbiosis influences the structure of plant communities in ecosystems worldwide.

The long-term goals of our research are to understand the mechanisms underlying development of the AM symbiosis and phosphate transfer between the symbionts. A model legume, Medicago truncatula, and arbuscular mycorrhizal fungi, Glomus versiforme, Glomus intraradices and Gigaspora gigantea are used for these analyses. Currently, a combination of molecular, cell biology, genetic and genomics approaches are being used to obtain insights into development of the symbiosis, communication between the plant and fungal symbionts, and symbiotic phosphate transport.