Background and aims: Subsoil acidity with a high aluminium (Al3+) soil content inhibits root growth and proliferation of durum wheat (tetraploid AABB, Triticum turgidum) leading to poor nutrient and water uptake. This study evaluated the impact of Al3+-tolerantTaMATE1B allele on root and shoot traits of durum wheat grown in an acidic soil with a high Al3+concentration. Methods: Two durum wheat lines, Jandaroi–TaMATE1B with the TaMATE1B gene introgressed from Al3+-tolerant bread wheat and Jandaroi–null (a sister line lacking the Al3+-tolerant TaMATE1B allele), were grown in rhizoboxes in a glasshouse. We mapped root growth and proliferation over time and measured shoot traits and grain yield. Results: Introgression of the Al3+-tolerant TaMATE1B allele into durum wheat enabled root growth and proliferation below 0.25 m of the soil profile, where the soil pH was low (4.1, CaCl2 extract) with high Al3+ content (16.5 mg kg−1), and increased total root length and biomass at 42 days after sowing (DAS; Z33) by 38.3 and 22%, respectively, relative to the Jandaroi–null. Differences in root growth between the two lines were apparent from tillering stage (Z33) and by 50% anthesis (Z64), respectively. Jandaroi–TaMATE1B had 69.2% greater root biomass, 76.2% greater root length, 5.89% greater leaf area and 18% greater shoot biomass than Jandaroi–null at 50% anthesis (Z64). Time to anthesis and physiological maturity was delayed 6–7 days in Jandaroi–TaMATE1B, compared to Jandaroi–null. Jandaroi–TaMATE1B tended to have relatively greater, but not significantly different, shoot biomass, grain yield and yield components than Jandaroi–null. Conclusions: Introgression of the Al3+-tolerant TaMATE1B allele into durum wheat enabled root growth and proliferation down an acidic soil profile with a high Al3+ concentration. We assume that in the field where plants need to acquire water at depth differences in above-ground parameters would be amplified.