Germination and ROS detoxification in bell pepper (Capsicum annuum L.) under NaCl stress and treatment with microalgae extracts.

We evaluated the salt tolerance of hybrids of pepper (Capsicum annuum L.) during germination. Treatments were applied at 0, 25, and 50 mM NaCl with preparations of supplemental extracts of the microalgae Dunaliella salina and Phaeodactylum tricornutum to determine the percentage germination rate as well as measured indicators of oxidative stress caused by the salt treatments during seed germination. We found that root growth was favorably influenced by the microalgae leading to increased germination rate. Tissues were analyzed in terms of superoxide radical production, lipid peroxidation, and activity of antioxidant enzymes viz. superoxide dismutase, catalase, and glutathione peroxidase. Our results suggest that application of microalgae extracts significantly reduced (p < 0.05) superoxide radical production, as well as lower lipid peroxidation in comparison to plants without extracts of microalgae. The antioxidant enzymes increased in the presence of microalgae showing a significant difference (p < 0.05). The results suggest differences in oxidative metabolism in response to the magnitude of salt stress and concentrations of microalgae help mitigate salt stress in plants during the germination process.