Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/1/2008
Publication Date: 5/14/2009
Citation: Kochian, L.V., Magalhaes, J., Liu, J., Hoekenga, O., Pineros, M. 2009. Recent Advances on the Molecular Basis of Crop Aluminum Resistance. Meeting Proceedings.
Technical Abstract: The considerable genetic variability for aluminum (Al) resistance within many crop plant species has been utilized by plant breeders for a number of years to enhance Al resistance. But beyond this, genetic variability in Al resistance has been an excellent experimental resource that is being mined by researchers to elucidate the molecular basis for this trait. Because of the agronomic importance of Al toxicity, research on the identification of crop Al resistance genes has attracted significant interest from a number of laboratories around the world. This manuscript will present an overview on the considerable recent research progress on identification of genes underlying a primary mechanism of Al resistance: the release of Al chelating molecules such as low molecular weight organic acids from the root system, which consequently immobilize Al3+ at the root surface, preventing it from entering root cells. To date, the Al resistance genes that have been identified are from two different families of membrane transporters mediating organic acid efflux. For both types of transporters, Al-inducible regulation of transporter gene expression plays an important role in differential Al resistance. It is likely that differences in protein structure and function also play a role in differential resistance, although to date there is no data supporting this. The identification of genes conferring Al resistance now provides the molecular tools to address a worldwide agronomic problem that is only exceeded by drought stress with regards to abiotic limitations to crop production.