Group VII E thylene R esponse F actor diversification and regulation in four species from flood‐prone environments

Flooding events negatively affect plant performance and survival. Flooding gradients thereby determine the dynamics in vegetation composition and species abundance. In adaptation to flooding, the group VII E thylene R esponse F actor genes ( ERF ‐ VII s) play pivotal roles in rice and A rabidopsis through regulation of anaerobic gene expression and antithetical survival strategies. We investigated if ERF ‐ VII s have a similar role in mediating survival strategies in eudicot species from flood‐prone environments. Here, we studied the evolutionary origin and regulation of ERF ‐ VII transcript abundance and the physiological responses in species from two genera of divergent taxonomic lineages ( R umex and R orippa ). Synteny analysis revealed that angiosperm ERF ‐ VII s arose from two ancestral loci and that subsequent diversification and duplication led to the present ERF ‐ VII variation. We propose that subtle variation in the regulation of ERF ‐ VII transcript abundance could explain variation in tolerance among R orippa species. In R umex , the main difference in flood tolerance correlated with the genetic variation in ERF ‐ VII genes. Large transcriptional differences were found by comparing the two genera: darkness and dark submergence‐induced R umex   ERF ‐ VII s, whereas HRE2 expression was increased in submerged R orippa roots. We conclude that the involvement of ERF ‐ VII s in flooding tolerance developed in a phylogenetic‐dependent manner, with subtle variations within taxonomic clades.