As much as 40% of the world’s potentially arable lands are highly acidic (1). At low soil pH values (pH < 5.0), the toxic aluminum (Al) species Al3+ is released from soil clay minerals, damaging and stunting root systems and resulting in significant reductions in crop yields due to drought stress and nutritional deficiencies (2). Therefore, the development of cultivars exhibiting elevated levels of Al tolerance is important for improving crop yields on acid soils, particularly in developing countries where food security is quite tenuous.