Remodeling of Root Growth Under Combined Arsenic and Hypoxia Stress Is Linked to Nutrient Deprivation

The study examined the impact of combined arsenic (As) and hypoxia (Hpx) stress on root growth and nutrient regulation in Arabidopsis thaliana. It was found that this stress combination led to significant remodeling of root architecture, characterized by inhibited main root growth and enhanced root hair (RH) development, which appeared to be an adaptive strategy for nutrient uptake under stress. The dual stress caused severe nutritional disorders, affecting root transcriptome and plant mineral contents, with a notable deregulation of genes involved in root and RH growth. The study highlighted the role of redox and reactive oxygen species (ROS) signaling, as well as energy metabolism reorganization, in root architecture remodeling. The findings suggested that RH stimulation might help sustain plant growth despite stress-induced inhibition of root biomass accumulation, and emphasized the importance of redox regulation and NADPH oxidase activity in shaping root development under these conditions.