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

Abstract

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.CuO), purchased pristine CuO (P.CuO), or functionalized CuO (F.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.CuO and F.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.

Tomato Fruit Nutritional Quality Is Altered by the Foliar Application of Various Metal Oxide Nanomaterials

“…Moreover, after the second treatment and at harvest, there were no significant differences between the treatments and the controls. Similar findings were reported by Cantu et al, Adisa et al, and Barrios et al, where the nanotreatments had no effect on the chlorophyll content of Candyland red tomatoes (CuO and CuO-CA), Heirloom tomatoes (CeO 2 ), and Roma tomatoes (CeO 2 and CeO 2 -CA), at the end of the life cycle [11,12,16]. However, when the tomato was exposed to CuO and Al 2 O 3 NMs in the soil for 40 days, increased chlorophyll content was reported [42].…”

“…Several studies involving the exposure of metal oxide nanomaterials on tomato plants have shown similar nonsignificant effects. Cantu et al found that there was no net effect on the agronomical parameters when tomato plants were exposed to CuO NPs and grown to full maturity (120 days) [ 16 ]. Adisa et al and Barrios et al also showed that soil or foliar application of CeO 2 NPs on tomato did not alter plant growth at concentrations below 250 mg/kg and 250 mg/L when grown for 126 and 210 days, respectively [ 11 , 12 ].…”

“…Barrios et al and Adisa et al found antagonist effects on sugar content from tomato fruits exposed to CeO 2 NMs and CeO 2 -CA-functionalized NMs [ 43 , 44 ]. Moreover, soil application of CuO-CA-functionalized NMs decreased starch concentration in tomato fruit [ 16 ]. The observed increase in sugar content from exposures to Mn 3 O 4 and ZnO may be a response to stress.…”

“…All nanomaterials (Fe 3 O 4 , MnFe 2 O 4 , ZnFe 2 O 4 , Zn 0.5 Mn 0.5 Fe 2 O 4 , Mn 3 O 4 , and ZnO) were analyzed using a Panalytical Empyrean diffractometer according to Cantu et al [ 16 ]. The diffraction patterns were fitted using literature crystallographic data, FullProf suite software, and a Le Bail fitting [ 15 , 17 , 18 , 19 , 20 ].…”

“…The precursor and concentration ratios for each nanomaterial are shown in Table 1. [16]. The diffraction patterns were fitted using literature crystallographic data, FullProf suite software, and a Le Bail fitting [15,[17][18][19][20].…”