Flooding tolerance: O2 sensing and survival strategies

•Escape and quiescence are two antithetical strategies to survive flooding.•Stability of ethylene responsive factor (ERF) transcription factors during anoxia regulates anaerobic gene expression.•Targeted proteolysis of ERFs via the N-end rule pathway acts as a low-oxygen sensing mechanism in plant cells.•The emergence of adventitious roots is regulated by ethylene, H2O2 and pressure exerted by the outgrowing roots.•Large natural variation in flooding tolerance is observed in several plant species. The investigation of flooding survival strategies in model, crop and wild plant species has yielded insights into molecular, physiological and developmental mechanisms of soil flooding (waterlogging) and submergence survival. The antithetical flooding escape and quiescence strategies of deepwater and submergence tolerant rice (Oryza sativa), respectively, are regulated by members of a clade of ethylene responsive factor transcriptional activators. This knowledge paved the way for the discovery that these proteins are targets of a highly conserved O2-sensing protein turnover mechanism in Arabidopsis thaliana. Further examples of genes that regulate transcription, root and shoot metabolism or development during floods have emerged. With the rapid advancement of genomic technologies, the mining of natural genetic variation in flooding tolerant wild species may ultimately benefit crop production.