Uncovering How Auxin Optimizes Root Systems Architecture in Response to Environmental Stresses

Since colonizing land, plants have developed mechanisms to tolerate a broad range of abiotic stresses that include flooding, drought, high salinity, and nutrient limitation. Roots play a key role acclimating plants to these as their developmental plasticity enables them to grow toward more favorable conditions and away from limiting or harmful stresses. The phytohormone auxin plays a key role translating these environmental signals into developmental outputs. This is achieved by modulating auxin levels and/or signaling, often through cross talk with other hormone signals like abscisic acid (ABA) or ethylene. In our review, we discuss how auxin controls root responses to water, osmotic and nutrient-related stresses, and describe how the synthesis, degradation, transport, and response of this key signaling hormone helps optimize root architecture to maximize resource acquisition while limiting the impact of abiotic stresses.

Automated summary

Plants have developed mechanisms to tolerate a broad range of abiotic stresses since colonizing land, with roots playing a key role in acclimating plants through their developmental plasticity. The phytohormone auxin is crucial in translating environmental signals into developmental outputs by modulating auxin levels and signaling, often through cross talk with other hormone signals like ABA or ethylene. This review discusses how auxin controls root responses to water, osmotic and nutrient-related stresses, optimizing root architecture to maximize resource acquisition while limiting the impact of abiotic stresses.