A helping hand when drowning: The versatile role of ethylene in root flooding resilience

Ethylene plays a very important role as a stress signal for flooded plants, triggering a range of morphological and metabolic changes that help plants acclimate and survive these conditions. The present review surveys the current knowledge on the mechanisms underlying ethylene-dependent survival responses to waterlogging. We untangle the complexity of waterlogging signaling and response, focusing on root and shoot acclimation strategies mediated by ethylene. We describe how ethylene can have versatile roles in waterlogging tolerance, acting both as a local and long-distance signal during soil flooding and reoxygenation. We discuss the internal and external factors contributing to ethylene versatility in waterlogging responses. Finally, we highlight the current challenges and future research directions in the field, focusing not only on ethylene-mediated responses but also on flooding research applications in crop improvement.