Durum wheat (Triticum turgidum) is an important crop but grows poorly on acid soil because of its sensitivity to soluble Al3+. In contrast, hexaploid wheat (T. aestivum) possesses TaALMT1, a major gene for Al3+ tolerance located on chromosome 4D that is responsible for much of the variation in tolerance observed in this species. Han et al. introgress a fragment of the 4D chromosome containing TaALMT1 from hexaploid wheat into an elite durum cultivar and show that the fragment enhances root growth in acid soil. Since the Kna1 locus is also located on the chromosomal fragment, the ability of leaves to exclude Na+, a trait associated with salt tolerance, is also enhanced.
A fragment of the 4D chromosome containing TaALMT1, introgressed into an elite durum cultivar, shows that the fragment enhances root growth in acid soil.