Could Biostimulants with Plant Active Compounds Improve the Tolerance to Oxidative Stress in Prosopis alba (Griseb.)?

The aim of this work was to explore the potential of four phytoextracts derived from species with recognized antioxidant activity and/or rich in polysaccharides as plant biostimulants of seedlings of Prosopis alba. Malondialdehyde (MDA), an oxidative stress biomarker, was measured at 21 days after the acclimation phase beginning as preliminary results showed a significant accumulation of MDA in rustified seedlings compared with control seedlings at this time. As main results, rustified seedlings sprayed with I. paraguariensis and L. divaricata extracts showed lower MDA concentration than rustified seedlings without any phytoextract application. Both extracts were characterized by their antioxidant activity. These results suggest that natural extracts of I. paraguariensis and L. divaricata could be considered plant biostimulants, reducing oxidative stress biomarkers in P. alba.