Project description:The search for more effective methods to alleviate the negative effects of abiotic stresses in plants has motivated the experimentation of new technologies, namely nanotechnologies. It is in this context that the use of formulations containing hybrid silicon (Si) nanoparticles (NPs) and acting as delivery systems of the flavonoid quercetin was here investigated. These formulations, previously referred to as phyto-couriers, proved their efficacy in protecting textile hemp against salinity. We here broaden their application spectrum by studying the effects on an important crop model, tomato (Solanum lycopersicum cv. Micro-Tom). Two phyto-courier formulations, labelled GS1 and GS3, functionalized with 25 mg of quercetin and differing in the presence of trehalose were applied to salt-stressed plants (200 mM NaCl) by foliar spraying. Microscopy showed, under stress, a preservation of the palisade mesophyll cell structure in plants treated with the formulations. A trend towards decreased expression of some stress-responsive genes was observed in the leaves treated with the phyto-couriers. Shotgun proteomics confirmed the protective effects and the nano-biostimulant nature of the formulations, since several proteins involved in cytoprotection against oxidative stress were more abundant in control leaves treated with the pyto-courier. This was especially evident for the trehalose-containing GS3 formulation. Some proteins involved in chromatin remodelling were also more abundant in control leaves treated with GS3. Overall, the formulations showed promising results to enhance abiotic stress tolerance in a model crop through the mitigation of stress symptoms. The results presented are a proof-of-concept for the use of the phyto-courier nanotechnology in horticultural applications
