Impact of Nanoparticles on Oxidative Stress and Responsive Antioxidative Defense in Plants

Nanotechnology has emerged as a multidisciplinary field with a wide range of potential applications including agriculture, where nanoparticles (NPs) are making a mark in improving the efficiency of fertilizers and pesticides. Though the main aim of usage of NPs is enhanced crop growth and yield improvements, contemporary reports have indicated both positive as well as negative impacts of NPs on plants. Certain reports have postulated that NPs can induce phytotoxicity and have negative impacts on overall plant metabolism, but simultaneously the exclusive properties of NPs can be used to improve crop performance as well. Nevertheless, unspecified release of NPs into the ecosystem has raised global concern about their potential phytotoxic effects, which needs to be fixed for commercial and large-scale use of NPs for the betterment of crop production. One of the prime detrimental effects of NP release in the environment is induction of oxidative stress, which is a complex physiological, biochemical, and molecular phenomenon that accompanies virtually all biotic and abiotic stresses in higher plants and develops as a result of overproduction and accumulation of reactive oxygen species (ROS). Engineered NPs, whether carbon or metal based, have been reported to impart oxidative stress and ROS generation in many plants. In this chapter we discuss the oxidative stress induced by different NPs in plants as well as responsive antioxidant machinery including enzymatic and nonenzymatic antioxidative components in stressed plants.