مریم مظاهری

This study, first, evaluated different levels of NAA and KIN on Nicotiana tabacum callus induction from leaf explant. Two mg L-1 NAA with 0.1 mg L-1 KIN on Murashige and Skoog (MS) medium induced callus in explants. Then this level of NAA and Ki was used in cell suspension culture. Finally, the effects of different concentrations of nP-ZnO (0.06, 0.12, 0.24 mM) compared to ZnSO4 (0.03 mM; control) on cell toxicity in suspension culture were investigated. Zinc cell content was increased in suspension culture under ZnO NPs compared with ZnSO4, which was positively correlated with protein content. The ZnO NPs induced cell death more significantly than control. The oxidative stress induced higher negative effects at a concentration of 0.024 mM ZnO. SOD enzyme activity increased at all levels of ZnO. H2O2 decreased at concentrations lower than 0.12 mM nP-ZnO compared to control. The results showed that ZnO NPs more significantly induced cell death and stress-induction effect in tobacco cells in suspension culture.