Medicago truncatula as a model for understanding plant interactions with other organisms, plant development and stress biology: past, present and future

Ray J. Rose

doi:10.1071/FP07297

REVIEW (Open Access)

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Medicago truncatula as a model for understanding plant interactions with other organisms, plant development and stress biology: past, present and future

Ray J. Rose

+ Author Affiliations

- Author Affiliations

Australian Research Council Centre of Excellence for Integrative Legume Research, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia. Email: ray.rose@newcastle.edu.au

Functional Plant Biology 35(4) 253-264 https://doi.org/10.1071/FP07297
Submitted: 17 December 2007 Accepted: 16 April 2008 Published: 3 June 2008

Abstract

Medicago truncatula Gaertn. cv. Jemalong, a pasture species used in Australian agriculture, was first proposed as a model legume in 1990. Since that time M. truncatula, along with Lotus japonicus (Regal) Larsen, has contributed to major advances in understanding rhizobia Nod factor perception and the signalling pathway involved in nodule formation. Research using M. truncatula as a model has expanded beyond nodulation and the allied mycorrhizal research to investigate interactions with insect pests, plant pathogens and nematodes. In addition to biotic stresses the genetic mechanisms to ameliorate abiotic stresses such as salinity and drought are being investigated. Furthermore, M. truncatula is being used to increase understanding of plant development and cellular differentiation, with nodule differentiation providing a different perspective to organogenesis and meristem biology. This legume plant represents one of the major evolutionary success stories of plant adaptation to its environment, and it is particularly in understanding the capacity to integrate biotic and abiotic plant responses with plant growth and development that M. truncatula has an important role to play. The expanding genomic and genetic toolkit available with M. truncatula provides many opportunities for integrative biological research with a plant which is both a model for functional genomics and important in agricultural sustainability.

Additional keywords: abiotic stress, biotic stress, Jemalong 2HA, legumes, nodulation, regeneration.

Acknowledgements

Work in my laboratory on Medicago truncatula has been supported by the Wool Research and Development Corporation, the Grains Research and Development Corporation, The University of Newcastle and currently by an ARC Centre of Excellence Grant for Integrative Legume Research (CILR) to the Universities of Queensland, Melbourne and Newcastle, and the Australian National University (Grant CEO348212). I wish to thank my colleagues from the CILR and my research group for the many stimulating discussions on Medicago truncatula biology; and also Lowell Johnson (KSU) and Ian Kaehne and Andrew Lake (formerly of SARDI) for introducing me to annual Medicago.

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