Molecular mechanisms of plant adaptation to acid soils: A review

Acid soils are widespread and limit global plant production. Aluminum (Al)/manganese (Mn) toxicity and phosphorus (P) deficiency are the major limiting factors affecting plant growth and productivity on acid soils. Plants, however, have evolved various strategies to adapt to these stresses. These strategies include using both external and internal mechanisms to adapt to Al toxicity, regulating Mn uptake, translocation, and distribution to avoid Mn toxicity, and orchestrating a set of P transport mechanisms to efficiently take up P from the soil. Here, we review the current state of knowledge about the molecular mechanisms of plant adaptation to these constraints in acid soils, focusing on the roles of transporters involved in Al/Mn tolerance and P efficiency. Gene manipulation combined with other biotechnology will contribute to the development of novel strategies to improve plant adaptation to acid soils. The molecular mechanisms of plant coadaptation to multiple stresses in acid soils are largely unknown and require further investigation.