Evaluation of Oxidant and Antioxidant Systems in Drought Response of Cowpea Varieties

Plant in their natural environment are exposed to several stresses such as the drought that affect their growth and productivity. Exposure of plant to drought leads to oxidative stresses as a result of increase in ROS, however plant counteract this effect by its antioxidant system. H 2 O 2 , malondialdehyde, membrane stability index, catalase and ascorbate peroxidase activities where evaluated in leaves of two cowpea varieties drought tolerant (Dan’ila) and drought susceptible (TVU 7778) during 2 weeks water deficit and 5days recovery. The result indicates significant increase in the H 2 O 2, MDA, CAT and APX activities in both varieties during the stress period and significant decrease during recovery in drought tolerant variety compared to the drought susceptible variety. The membrane stability index decreases significantly during stress period in both varieties. Drought tolerant variety has the higher ability to counteract oxidant activity during the drought stress and recover faster than the drought susceptible variety. Keywords : Drought, antioxidant, cowpea DOI: 10.7176/JNSR/12-8-03 Publication date: April 30 th 2021