Responses of two Asteraceae to metal stress: Evaluation tolerance lead, barium and some rare earths in Helianthus annuus Limbarda crithmoides

Industrial development and disrupt the balance of the global system. In fact, we have have witnessed an increase in the quantities of metallic elements metallic elements into the environment. These inorganic pollutants are becoming a worldwide concern because of their high toxicity, which threatens our ecosystems, especially when they enter the food chain. As a result, the exploitation of species known for their tolerance to metal pollutants could be a promising approach to improve the productivity of contaminated productivity of contaminated areas, as well as identifying hyperaccumulative plants for possible use in phytoremediation programs. phytoremediation programs. H. annuus and L. crithmoides tolerate high concentrations of metallic elements thanks to physiological and biochemical mechanisms including activation of the antioxidant system, increased secondary metabolites and photosynthetic pigments. H. annuus has a high accumulation capacity for metal elements, while L. crithmoides is hyperaccumulative for Ba but sensitive to rare earths.