Physiological effects of TiO2 nanoparticles on wheat (Triticum aestivum)

Nanoparticles (NP) are introduced in a growing number of commercial products and their production may lead to their release in the environment. Plants may be a potential entry point for NP in the food chain. Up to now, results describing NP phytotoxical effects and plant accumulation are scarce and contradictory. To increase knowledge on titanium dioxide NP (TiO2-NPs) accumulation and impact on plants, we designed a study on wheat (Triticum aestivum). This plant was exposed to TiO2-NPs, with diameter 20 nm, either anatase or rutile. Green house trials were conducted to evaluate the influence of TiO2 on physiological characters. Seven parameters are examined in this study: shoot and root length, fresh and dry biomass of shoot and root and leaf chlorophyll content. The results showed that there is no significant effect on shoot and root length of wheat under nano-TiO2 spraying, however nano- TiO2 is observed to have detrimental effects on wheat shoot and root biomass.TiO2 nanoparticles has no effect on chlorophyll content compare to control except treatment of 1000 mgL-1.This study shows that direct exposure to specific types of nanoparticles causes significant phytotoxicity, emphasizes the need for ecologically responsible disposal of wastes containing nanoparticles and also highlights the necessity for further study on the impacts of nanoparticles on agricultural and environmental systems.