Recent Progress of Nanotoxicology in Plants

Nanoparticles (NPs) have various considerable implications, especially in agriculture, biomedical engineering, and environmental remediation techniques, making it critical to evaluate their role in the environment and plant species. NPs are extensively being used widely in many industries because of their unique properties. However, this leads to their discharge into the surrounding environments and absorption by plants. The quality of foodstuff obtained from NP-enriched plants is questionable and current research is focused on this environmental problem. This chapter addresses the role of NPs in agriculture, and their toxic effects on different physiological, biochemical, and quality parameters of plants. Moreover, types and characteristics of NPs are also discussed in this chapter. There are different types of NPs such as graphene, nanoscale zero-valent iron, NiO, fullerene, CuO, ZnO, SiO 2, carbon nanotube, Ag, and CeO 2. The use, functions, and potential toxic effects of NPs depend upon their physicochemical properties, concentration, and interaction with plant species. The toxic effects of NPs can be avoided by controlling various factors such as diameter, surface area, and appropriate route selection. It is widely accepted that phytotoxicity of NPs is evidenced by genotoxicity, increase in reactive oxygen species (ROS) and reduction in antioxidative enzymes. NPs first interact with the cell walls. After entering the cells, they may aggravate alterations of membranes, molecules, and cell organelles, increasing solubilization of harmful NPs and ROS production. In addition, there is an intrinsic plant detoxification mechanism of NPs when exposed to nanotoxicity. Free metal radicals, which are produced during oxidative stress, work as signaling molecules, hence activating the ROS detoxification and antioxidant defense mechanism in plants to cope with NP toxicity. In the future, a closer view of nanomaterial-driven phytotoxicity is required to specify how these NPs affect plant biota.