Exogenous foliar ascorbic acid applications enhance salt-stress tolerance in peanut plants throughout an increase in the activity of major antioxidant enzymes

Author(s)

Alves, Rita de Cassia ; Oliveira, Kevein Ruas ; Barbosa Lucio, Jose Clebson ; Silva, Jeferson dos Santos ; Carrega, Willians Cesar ; Queiroz, Samira Furtado ; Gratao, Priscila Lupino

• Document type: Journal article
• Source: SOUTH AFRICAN JOURNAL OF BOTANY; v. 150, p. 9-pg., 2022-08-27.

Abstract

Although ascorbic acid (AsA) is an antioxidant that can protect plants from oxidative damages, little is known about physiological and biochemical responses of exogenous AsA-regulated antioxidant systems to stressful -conditions in peanut plants. This study aimed to evaluate the effects of AsA-foliar applications on antioxidant defense responses in peanut plants irrigated with saline water. The experiment was carried out in a completely randomized design with four treatments formed by combining and not AsA under salt-stressful conditions (control, 50 mM AsA, 50 mM NaCl and 50 mM NaCl + 50 mM AsA). AsA application was performed twice a week spraying plant shoot. After a period of 40 days post germination, plants were collected and eval-uated for the following parameters: total chlorophyll and carotenoids contents; dry biomass; malondialde-hyde (MDA) and H2O2 contents, superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione peroxidase (GSH-Px) and glutathione reductase (GR). AsA increased total chlorophyll and carot-enoid contents, reduced Na+concentration, and oxidative damages by modifying antioxidant defense sys-tems. Therefore, the exogenous application of AsA is an efficient strategy to withstand or avoid stress imposed by salt, which can be attributed to increased SOD, CAT, APX, GSH-Px and GR activities in peanut plants, and enhance salt tolerance. (c) 2022 SAAB. Published by Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 17/04787-6 - Selenium modulation in ethylene synthesis and cadmium tolerance
• Grantee: Priscila Lupino Gratão
• Support Opportunities: Regular Research Grants