Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 7/22/2010
Publication Date: 1/11/2011
Citation: Hoekenga, O., Magalhaes, J. 2011. Mechanisms of aluminum tolerance. In: Oliveira, A.C., Varshney, R., editors. Root Genomics. Verlag Berlin, Heidelberg: Springer. p. 133-153.
Technical Abstract: Aluminum (Al) toxicity limits agricultural productivity over much of the world’s arable land by inhibiting root growth and development. Affected plants have difficulty in acquiring adequate water and nutrition from their soil environments and thus have stunted shoot development and diminished yield. Al toxicity is due to soil acidity and is largely a natural problem; however, it can also result due to excessive use of ammonia-based fertilizers. Many plants utilize Al tolerance mechanisms that depend upon excluding Al from the root tip, which is the most sensitive part of the root system to Al toxicity. Al exclusion is often mediated by citrate or malate release from roots by Al activated transporters. Recently, major Al tolerance loci have been cloned and represent citrate (AltSB from sorghum) or malate (TaALMT1 from wheat) transporters. While other Al tolerance mechanisms have some support, systems biology approaches are making good progress to describe them more fully. Thus, it is an exciting time to study the mechanisms of Al tolerance and apply this knowledge to crop improvement via marker-assisted breeding and translational genomics.