This study aimed to evaluate the synergy between arbuscular mycorrhizal fungi (AMF) and foliar biostimulant applications (phytoextracts) on an important Argentinian forest native species (Prosopis alba) during the nursery stage. We tested biochemical parameters (MDA, malondialdehyde, an oxidative stress biomarker, and photosynthetic pigments) on P. alba seedlings sprayed with three different phytoextracts and inoculated with mycorrhizal strains of different local origins. Considering that the statistical model was not significant at the preliminary level, we did not observe synergism between the different forms of bioinsumes evaluated by analysing biochemical characteristics. However, regardless of AMF inoculation, plants with foliar applications of Larrea divaricata at 3% w/v showed a lower accumulation of the oxidative stress biomarker, MDA and a lower total carotenoid content (p > 0.1). Although there were no significant differences, trends indicate positive relationships between neck diameter and mycorrhizal response in plants treated with M1 with foliar applications of Larrea divaricata at 3% w/v. However, height does not consistently respond to mycorrhizae interacting with biostimulants. Consequently, deeper analysis is needed to understand the effect of the interaction between AMF with biostimulants for improving the plant’s physiological status. Deepening research in this regard will result in significant benefits for restoration activities.

This study assessed how the interactions between chemical fertilization levels and arbuscular mycorrhizal fungus species (AMF) affect the seedling’s morphology and biochemical traits in Prosopis alba. Subsequently, the seedlings were inoculated or not with a mixture of native AMF from two origins of contrasting sites in the Chaco Region. Preliminarily, we observed a positive mycorrhizal response to the AMF in interaction with chemical fertilization (at 60% fertilizer concentration). These results were reflected mainly over some morphological parameters than over biochemical parameters. The lack of a clear answer is probably since the benefits of the symbiosis on the host plant could be observed in the establishment phase in the field.

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.