Advances in Molecular Mechanisms Underlying Cadmium Accumulation and Detoxification in Durum Wheat (Triticum turgidum L. subsp. durum (Desf.) Husn.)

Cadmium (Cd) pollution adversely affects crop productivity and grain quality. Durum wheat (Triticum turgidum L. subsp. durum (Desf.) Husn.), a widely consumed cereal crop, can accumulate substantial levels of Cd in edible tissues, threatening human health. Therefore, advances in understanding Cd toxicity in plants and the molecular mechanisms underlying Cd accumulation and detoxification are needed to develop resistant cultivars and ensure safe food production. Although Cd homeostasis has been previously studied in bread wheat, its accumulation varies among species and cultivars owing to differences in their physiological and genetic makeup. However, the molecular mechanisms underlying Cd homeostasis in durum wheat have not been comprehensively reviewed. Here, we synthesize current knowledge on the molecular basis of Cd uptake, transport, and detoxification in durum wheat. Specialized transporter families, including MRPs/ABCCs, HMAs, and members of the YSL, ZIFL, and IREG families, play critical roles in mediating Cd compartmentalization and limiting its cytosolic toxicity. Genes such as HMT1, TdHMA3-B1a, and members of the NAS gene family significantly reduced Cd accumulation in grains. Future studies should focus on the integration of physiological, molecular genetics, and multi-omics approaches to uncover the regulatory networks controlling Cd homeostasis in durum wheat.