Abstract
Salinity is an abiotic factor that severely limits agricultural yield around the world. Tomatoes are important crops among others due to their high nutritional value; however, when the crop is exposed to abiotic stresses such as salinity, tomato production could be negatively affected. The goal of this study was to measure the morphological and physiological responses of tomato seedlings grown under salt stress when carbon nanoparticle of oil fly ash (COFA) under heat treatment in the concentration (5 mg L-1) was applied to the leaves. In this study, three carbon nanoparticles (COFA, COFAH-J, COFAH-R) were applied to tomato seedlings under three different salt (NaCl) treatments: 0 mM, 20 mM, and 40 mM. For each treatment, three biological replicates were conducted, with each replicate containing at least three plants. Our findings demonstrated that salt-stressed tomato plants had considerably lower length of shoot and root, biomass, and photosynthetic pigments over control plants. Furthermore, salinity greatly enhanced the proline concentration, superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities. However, the application of thermally treated carbon nanoparticles resulted in increases in the quantities of photosynthetic pigments and plant growth conditions. However, the tomato seedlings treated with COFA, COFAH-J, and COFAH-R increased SOD activity by 65%, 53%, and 45%; CAT activity by 67%, 63%, and 65%; and APX activity by 51%, 52%, and 41%, respectively, when seedlings were exposed to 40 mM. Overall, our data suggest that heated carbon nanoparticles of oil fly ash may improve tomato plants' salt tolerance by enhancing their antioxidant defense systems. The beneficial impacts of thermally treated carbon nanoparticles in tomato plants offer up new avenues for their potential innovations in novel agricultural methods, particularly while plants are grown to saline conditions.