IMPACT OF CHEMICALLY SYNTHESIZED ZINC OXIDE NANOPARTICLES ON SALINE STRESSED WHEAT

Nanotechnology is such a multidisciplinary technique comprises agriculture, medicine, fabrics, electronic, food packaging because it's several engineering methodologies, but still needing much research because of controversial issues about safety and toxicity. Our present study was performed in two successive seasons of 2018 through 2020 to determine the effect of chemically engineered ZnO nanoparticles (NPs) on salinity stress tolerance to wheat cultivars Misr1 (tolerant) and Gimmeza11 (sensitive). Data showed an increase of some biochemical parameters such as photosynthetic pigments, reduced glutathione increased intensity of some native PAGE bands of superoxide dismutase which may be related to salt tolerance and decreasing malondialdehyde. Some changes in protein biosynthesis of wheat leaves were observed between presence (1) or absence (0) of some bands due to the application of ZnO NPs which may be related to the antagonistic effect between metals among them Zn. The most effective concentration was 1.0ppm for most determined parameters. ZnO NPs was evaluated on molecular DNA level of wheat plant using Inverse sequence-tagged repeat (ISTR) assay against five primers which appeared change in bands number with highest polymorphic bands 86.6% polymorphism at F9, B3 primer and 20 unique bands with primer F4, B7, values indicates the degree of alterations in DNA according to the highest polymorphic bands which treated with ZnO NPs as compared with the control but we can't ignore the role of DNA repair system enzymes. The biological study revealed the effectiveness of ZnO NPs as a foliar spray on two wheat cultivars (Misr 1 and Gimmeza11). So, to clarify their safety we explored the median lethal dose (LD50) on Wistar Albino rats and repeated doses for 28 days. ZnO NPs have no effect on the levels of liver or kidney functions and histopathological cases, all of which remained within the normalized values so that, the debate about using ZnO NPs application in fields in wide spectrum may be turned off.