Combined Effect of Zinc Oxide Nanoparticles and Bacteria on Osmolytes and Antioxidative Parameters of Rice (Oryza sativa L.) Plant Grown in Heavy Metal-Contaminated Water

With the advancement in nanotechnology, use of nanoparticles has been enhanced dramatically biomedical, agriculture, and industrial processes. However, combined effect bacteria on plant growth heavy metal (Cd, Cr, Cu, Pb)-contaminated wastewater is greatly limited. Therefore, recent work was designed to determine synergistic impact green synthesized zinc oxide (ZnO-NPs) (5-10 mg/L) Bacillus spp. (Bacillus cereus Lysinibacillus macroides) physiological biochemical activities rice seedlings under metal- (HM-) contaminated water. The results revealed that germination percentage (36%), root-shoot length (5.11 3.41 cm), fresh shoot-root weight (0.05 0.011 g), dry (0.008 0.009 Chl a, b, carotenoid (5.4, 3.2 mg/g, 4.3 μg/g), total soluble sugar (TSS) (26.44 mg/g), protein (TSP) (21.99 mg/g) content considerably reduced tissues while ZnO NPs alleviates HM stress water improved seed (70%), (9.93 11.82 (0.125 0.131 (0.0532 0.042 (18.8, 13.9 17.1 TSS (57.651 TSP (47.990 content. Lipid peroxidation induced by increased amount thiobarbituric acid reactive substances (TBRAS) (17.321 nM/mg) hydrogen peroxide (H2O2) (14.5 μM/g), markers such as glycine betaine (GB) (40.731 proline (Pro) (38.812 μmol/g) antioxidant enzymes (SOD, POD, CAT, APX) (180.87 U/mg, 450.677, 0.1066, 0.631 μm/min/mg) TBRAS (5.431 nM/mg), H2O2 (2.25 GB (24.731 Pro (18.811 μmol/g), SOD, APX (187.53, 194.88, 0.061, 0.271 contents. present study suggested a potential role remediation metals from improving growth.