Antioxidant mechanisms involved in the control of cowpea root growth under salinity

Abstract

Salinity affects plant productivity in all agricultural crops. In the Brazilian semiarid region, considered one of the most salinized areas in Brazil, the cultivation of cowpea beans (Vigna unguiculata) is of paramount importance for the region's economy and food security. However, the development of the plant roots is affected by the inherent salinity of the soils. In addition to its direct effects, salt stress can cause osmotic stress and oxidative stress. The latter occurs when there is an imbalance between the production and removal of reactive oxygen species (ROS), which in general is a sign of stress in the plant, as in excess ROS can cause oxidative damage in cell membranes. Saline stress in the Brazilian semiarid region can cause a reduction in the size of cowpea roots but without apparent peroxidation of the membranes, suggesting that stress caused by salinity does not induce oxidative damage in root membrane lipids. Thus, this work presents evidence that the balance between the production and removal of ROS is crucial for responses related to the vegetative growth of cowpea roots.