Metal oxide nanoparticles and plants

Phytosynthesis is one of the popular methods used to synthesize metal oxide nanoparticles, in which plant extracts are used as ecofriendly reducing and stabilizing agents. Nanoparticles have the tendency to be bioaccumulated and transported to the edible parts of the plants, eventually causing health hazards. Herein, we have considered selected metal oxide nanoparticles frequently synthesized through biogenic approaches and reviewed their potential implications on the growth and physiology of plants. The literature review suggested that the toxicity of metal or metal oxide nanoparticles varies relative to the plant species and the nanoparticles used. Mostly, the toxicity is dose-dependent and varies with the nature of the nanoparticles. The toxicity of nanomaterials is manifested in plants through different mechanisms such as blocking nutrient uptake and transport, photosynthetic stress, enzymatic disruption, ROS generation, DNA damage, etc. Although green synthesis results in relatively compatible nanoparticles, however, a holistic approach needs to be adopted to investigate its interaction with plants.