Damage and Protection of the Photosynthetic Apparatus Under Cadmium Stress

Cadmium (Cd) is one of the most toxic pollutants that may cause potentially harmful effects on crops. Accumulation of Cd in the plant tissues is influenced by the levels of Cd available in the soil in which the plants are grown. It is known that Cd ions cause alterations in the functionality of photosynthetic membranes by affecting the lipid composition, the chlorophyll metabolism, the chloroplast ultrastructure, and the activity of both photosystems. The study of signaling molecules that mediate Cd stress tolerance is an important step in better understanding how plants can acclimate to the adverse environment. Here we review the protection role and mechanisms of action of some plant growth regulators, such as brassinosteroids, salicylic acid, gibberellic acid, and gibberellin-insensitive DELLA proteins on the photosynthetic apparatus under Cd stress.