Citric Acid-Functionalized CuO Nanoparticles Alter Biochemical Responses in Candyland Red Tomato (Solanum lycopersicum)

Investigations on the effects of copper-based nanoparticles (NPs) on plant growth and fruit production have increased recently. However, limited studies have demonstrated the different impacts of pristine and surface-modified CuO NPs on tomato plants. In this study, Solanum lycopersicum Candyland Red variety tomatoes were exposed to either 50 or 500 mg/kg of synthesized pristine CuO (S center dot CuO), purchased pristine CuO (P center dot CuO), or functionalized CuO (F center dot CuO) NPs via soil application and grown to full maturity (120 days). After harvesting, total soluble proteins in the roots were increased by CuO treatments, while the starch content in the fruit decreased by P center dot CuO and F center dot CuO treatments at both concentrations tested. The bioactive compounds tested (total phenols, flavonoids, and lycopene) were unaffected by any nanotreatment. Moreover, the exposure to CuO caused Cu and Fe redistribution throughout the whole plant and fruit. This study demonstrated how functionalization of NPs can induce different biochemical responses in plants.