Influence of Nanomaterials on Physiology and Antioxidant Defense Activities in Plants Under Abiotic Stress Conditions

Abiotic stressAbiotic stress causes a major loss in crop productivityProductivity; therefore, approaches to counteract stressStress repercussions are needed. The recent advancement in nanotechnologyNanotechnology has paved the way for agricultureAgriculture, and researchers are formulating nano-fertilizers, nanocarbons, etc. that should reduce the abiotic stress caused to plants. NanomaterialsNanomaterial (NM) (NMs) are colloidal solid particles composed of carbon, metalMetal, metal oxides, or organic matter, and their size range is between 1 and 100 nm. NMs are known to possess unique general properties (physical, biological, and chemical), particularly shape, size, charge, surface area, and surface reactivity, compared to their particles at larger sizes. NMs consist of 3 layers: (a) the surface layer: this layer can be made to work with several small molecules, polymers, metal ions, and surfactants; (b) the shell layer: it differs from the core layer chemically; and (c) the core layer: the central region of NMs. Due to their special characteristics the nanomaterialsNanomaterial (NM) (NMs) have a regulatory role in the physiology and biochemistry of crop plants, as they enhance the production of various enzymatic antioxidants (catalase: CAT, glutathione-S-transferaseGlutathione-S-transferase (GST): GST, superoxide dismutaseSuperoxide dismutase (SOD): SOD, and peroxidasePeroxidase (POD): POD), non-enzymatic antioxidants (ascorbateAscorbate: AsA, glutathioneGlutathione: GSH), secondary metabolitesSecondary metabolites (phenols, flavonoidsFlavonoid, and anthocyanins), and other macromolecules like carbohydrates and proteins, which can bring the plants back to a salubrious condition. Moreover, NMs also have a role in instigating various secondary messengers and defense responsesResponse by regulating stressStress-responsive genes. Looking at the role of NMs in regulating abiotic stressAbiotic stress the present chapter discusses the role of NMs under abiotic stressStress conditions in plants.