Root growth plasticity determines the survival of plants to continuous changing environmental cues.Aluminum (Al) stress is one of the most widespread phytotoxicity problems globally in acid soils, and typical and easily observed symptom of Al toxicity is the rapid inhibition of root growth.Although much progress has been made during recent years in the understanding of Al resistance, the molecular and physiological mechanisms on Al-induced inhibition of root elongation are still not well understood.Our recent investigations suggest that Al stress induced local auxin biosynthesis in the root apex transition zone plays an important role in root growth inhibition in response to Al stress.