Cerium alleviates drought-induced stress in Phaseolus vulgaris

Extreme drought events are expected to be one of the main challenges for tropical agriculture and,consequently,for global food security.For this reason,it is urgent to develop strategies to increase water use efficiency,as well as to increase crops’ ability to cope with drought.Because rare earth elements(REEs) are known to alleviate damages in plants under abiotic stresses,we hypothesized that addition of Ceto nutrient solution would promote the growth of common bean,especially under simulated drought stress.To test this hypothesis,we conducted an experiment evaluating the effect of six Ceconcentrations on the development and physiological traits of common bean grown in nutrient solution under normal condition and under induced drought stress,caused by the addition of polyethylene glycol6000 to the nutrient solution.Our results show that Cealleviates water stress in common bean plants,increasing their survival rate and growth.In addition,Ceapplication increases photosynthesis rate,chlorophyll content and water use efficiency under water stress.However,we observe no significant effect of Ceon plants growing under normal condition.Therefore,Ceseems to be a promising attenuator of drought stress for common bean.