The aim of this project is to identify mechanisms that contribute to highly efficient biological nitrogen fixation in legumes

Legumes have evolved symbioses with nitrogen fixing bacteria which provide nitrogen fertiliser to those plants. We are interested in the genetic and physiological adaptation in legumes that have paved the way for nitrogen fixing symbioses in legumes, as well as defining the key legume traits that contribute to highly efficient symbiosis, especially under nitrogen limitation and future predicted heat stress and elevated atmospheric CO₂ concentrations.

We are working across model and crop legumes (mainly Medicago truncatula and chickpea, respectively) to identify genetic, physiological and biochemical traits of legumes that contribute to optimal association with nitrogen-fixing bacteria, while minimising concurrent loss fro pathogens and parasites. We are using advanced phenotyping tools, simulated environments with future climate conditions and a combination of metabolomics, genetic screening and gene editing to find new mchaistic insights into the major controbutors to effieicnt symbiosis in legumes.

Recent key publications

• Mathesius U (2022) Humbold Review: Are legumes different? Origins and consequences of evolving nitrogen fixing symbioses. Journal of Plant Physiology 276: 153765.
• Zhang RY, Massey B, Mathesius U, Clarke VC (2023) Photosynthetic gains in super-nodulating mutants of Medicago truncatula under elevated atmospheric CO₂ conditions. Plants 12: 441.
• Qiao Y, Miao S, Jin J, Mathesius U, Tang C (2021) Differential responses of the sunn4 and rdn1-1 super-nodulation mutants of Medicago truncatula to elevated atmospheric CO₂. Annals of Botany 128: 441-452
• Rae AE, Rolland V, White R, Mathesius U (2021) New methods for confocal imaging of infection threads in crop and model legumes. Plant Methods 7: 24.
• Costa SR, Ng JLP, Mathesius U (2021) Interaction of symbiotic rhizobia and parasitic root-knot nematodes in legume roots – from molecular regulation to field application. Molecular Plant-Microbe Interactions 35: 470-490.
• Mens C, Hastwell AH, Su H, Gresshoff PM, Mathesius U, Ferguson BJ. (2020) Characterisation of Medicago truncatula CLE34 and CLE35 in nitrate and rhizobia regulation of nodulation. New Phytologist 229: 2525–2534.
• Costa SR, Chin S, Mathesius U (2020). Infection of Medicago truncatula by the root-knot nematode Meloidogyne javanica does not require early nodulation genes. Frontiers in Plant Science 11: 1050.
• Veliz-Vallejos DF, Kawasaki A, Mathesius U (2020) The presence of plant-associated bacteria alters responses to N-acyl homoserine lactone quorum sensing signals that modulate nodulation in Medicago truncatula, Plants 9: 777.
• Gauthier-Coles C, White R, Mathesius U (2019). Nodulating legumes are distinguished by a sensitivity to cytokinin in the root cortex leading to pseudonodule development. Frontiers in Plant Science 9: 1901.
• Li Y, Yu Z, Liu X, Mathesius U, Wang G, Tang C, Wu J, Liu J, Zhang S, Jin J (2017) Elevated CO₂ increases nitrogen fixation at the reproductive phase contributing to various yield responses of soybean cultivars. Frontiers in Plant Science 8:1546
• Van Noorden GE, Verbeek R, Dinh QD, Jin J, Green A, Ng JLP, Mathesius U (2016) Molecular signals controlling the inhibition of nodulation by nitrate in Medicago truncatula. International Journal of Molecular Sciences 17: 1060
• Jin J, Watt M and Mathesius U (2012) The autoregulation gene SUNN mediates changes in root organ formation in response to nitrogen through alteration of shoot-to-root auxin transport. Plant Physiology 159: 489-500.
• Plet J., Wasson A., Ariel F., Le Signor C., Baker D., Mathesius U., Crespi M., and Frugier F. (2011) MtCRE1-dependent cytokinin signaling integrates bacterial and plant cues to coordinate symbiotic nodule organogenesis in Medicago truncatula. Plant Journal 65, 622–633
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