Improving the effects of salt stress by β-carotene and gallic acid using increasing antioxidant activity and regulating ion uptake in Lepidium sativum L.

Background: Plant growth and development are severely affected by soil salinity. This study was carried out to evaluate the interaction of foliar application of antioxidants (beta-carotene and gallic acid) and salt stress on Lepidium sativum seedlings. Results: Our findings revealed that total dry and fresh weight were adversely affected by 25 mM NaCl salinity stress. Moreover, K+ content decreased while Na+ content increased significantly. The foliar application of beta-carotene and gallic acid significantly mitigated the effects of salt stress by regulating ion uptake, reducing H2O2 and malondialdehyde (MDA) content, as well as increasing enzymatic antioxidant activity, phenolic, glutathione, and chlorophyll content. Conclusions: beta-carotene- and gallic acid-treated plants had higher salt tolerance.