Effect of TiO2 Nanoparticles on Antioxidant Enzymes Activity and Biochemical Biomarkers in Pinto Bean (Phaseolus vulgaris L.)

Abstract

Tests were done on the effects of titanium dioxide spray on Pinto bean (Phaseolus vulgaris L. c.v ‘c.o.s.16’). The study was conducted as a factorial experiment in a randomized complete block design with four replications for two years (2014 - 2015). Treatments consisted of two factors; the first factor was stage of plant growth that spraying was applied (rapid vegetative growth, flowering and pod filling); and the second factor was that of different concentrations of titanium dioxide nanoparticles (TiO<sub>2</sub>) that consisted of spray with water (control), nano titanium dioxide at concentrations of 0.01%, 0.02%, 0.03% and 0.05%. Activity of guaiacol peroxidase (GPX), activity of superoxide dismutase (SOD), activity of catalase (CAT), activity of peroxidase (POD), malonyldialdehyde (MDA) Content and 8-deoxy-2-hydroxyguanosine (8-OHDG) content were assayed. Results showed that effect of nano TiO<sub>2</sub> was significant on activity of superoxide dismutase (SOD), activity of catalase (CAT), activity of peroxidase (POD), malonyldialdehyde (MDA) Content and 8-deoxy-2-hydroxyguanosine (8-OHDG) content. Results of combined analysis of variance showed that the effect year significantly affected on SOD and 8-OH-2-DG (P ≤ 0.05). The effect of different amounts of titanium dioxide nanoparticles (TiO<sub>2</sub>) significantly affected (P ≤ 0.05) on MDA and 8-OH-2-DG. The effects of different amounts of titanium dioxide nanoparticles and year were significant on SOD, POD, MDA and the amount of 8-deoxy-2-hydroxyguanosine in P ≤ 0.05. None of the physiological traits were affected by spraying of nano titanium dioxide. The effects of TiO<sub>2</sub> nanoparticles times of spraying and year were significant on SOD, CAT and 8-deoxy-2-hydroxyguanosine (P ≤ 0.05). Interaction effects of nano TiO<sub>2</sub> concentrations × nano TiO<sub>2</sub> spraying times did not have a significant impact on SOD, CAT, POD, GPX, MDA and 8-OH-2-DG. Although, all trait were affected by interaction effects of year × nano TiO<sub>2</sub> concentrations × nano TiO<sub>2</sub> spraying times with the exception of GPX (P ≤ 0.05).