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Aluminium toxicity: Towards an understanding of how plant roots react to the physical environment

  • Chapter
Genetic Aspects of Plant Mineral Nutrition

Part of the book series: Developments in Plant and Soil Sciences ((DPSS,volume 50))

Abstract

The root cap has an established but poorly understood role in determining the roots’ response to the physical environment (including Al). Data from studies of Al toxicity are combined with more general aspects of root physiology to develop understanding of the basis for Al toxicity as well as the regulatory systems involved in mediating a transmitted response between Al-damaged cap cells and the responding cells of the cap and root.

Pivotal roles are identified for the physiology of the cap mucilages in the stimulus transduction pathway and links are indicated between the secretory activity of peripheral cap cells and primary events involved in signal perception.

This information is used to identify possible mechanisms of Al tolerance notably involving connections between root cation-exchange capacity and the chemistry of cap mucilage and root recovery from Al reflecting signal inactivation and biochemical adjustments directed at alleviating the stress condition.

New research prospects for extending our perception of Al tolerance are discussed.

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Authors and Affiliations

  1. Grasslands Research Centre, Private Bag X9059, Pietermaritzburg, 3200, Republic of South Africa

    R. J. Bennet & C. M. Breen

  2. Institute of Natural Resources, P.O. Box 375, Pietermaritzburg, 3200, Republic of South Africa

    R. J. Bennet & C. M. Breen

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  1. R. J. Bennet
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  2. C. M. Breen
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Editors and Affiliations

  1. Division of Plant Industry, Commonwealth Scientific and Industrial Research Organization (CSIRO), Canberra, Australia

    P. J. Randall , E. Delhaize , R. A. Richards  & R. Munns , ,  & 

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Bennet, R.J., Breen, C.M. (1993). Aluminium toxicity: Towards an understanding of how plant roots react to the physical environment. In: Randall, P.J., Delhaize, E., Richards, R.A., Munns, R. (eds) Genetic Aspects of Plant Mineral Nutrition. Developments in Plant and Soil Sciences, vol 50. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-1650-3_14

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