Growing on calcareous soils and facing climate change.

Soil calcium carbonate (CaCO) impacts plant mineral nutrition far beyond Fe metabolism, imposing constraints for crop growth and quality in calcareous agrosystems. Our knowledge on plant strategies to tolerate CaCO effects mainly refers to Fe acquisition. This review provides an update on plant cellular and molecular mechanisms recently described to counteract the negative effects of CaCO in soils, as well as recent efforts to identify genetic bases involved in CaCO tolerance from natural populations, that could be exploited to breed CaCO-tolerant crops. Finally, we review the impact of environmental factors (soil water content, air CO, and temperature) affecting soil CaCO equilibrium and plant tolerance to calcareous soils, and we propose strategies for improvement in the context of climate change.