Chapter 15 - Seed priming with engineered nanomaterials for mitigating abiotic stress in plants

Abstract

Listen

Translate article

In the era of global climate change, agricultural production is facing numerous abiotic challenges such as salinity, heavy metals contamination, drought, heat, cold, and ultraviolet radiation. In addition, increasing population pressure and shrinking land resources are also imposing an additional load on agricultural systems for food security and sustainability. Seed priming with nanomaterials known as nano-priming has emerged as innovative priming technology as it is more efficient as compared to other seed priming methods. Nano-priming not only helps to improve seed germination, seedling growth, and yield but also have the potential to mitigate various biotic and abiotic stresses in plants. The mechanistic features of nanoparticles (NPs) in seed priming are to develop electron exchange and enhanced surface reaction capabilities associated with various components of plant cells and tissues. Nano-priming improves uptake of water absorption through formation of nanopores and induction of the expression of aquaporin genes, helps in maintaining cellular homeostasis through activating reactive oxygen species (ROS) and antioxidant systems in seeds, and forms hydroxyl radicals and activates cell wall degradation enzymes to loosen the walls of the cells. Moreover, nano-priming mediates ROS, dispersed over biological membranes and enhances the hydrolysis of starch and proteins by activating the hydrolyzing enzymes. The stimulation of amylase activity by nano-priming enhances starch degradation, which improves seed germination. Nano-priming produces a mild ROS activity, which acts as a primary signaling cue for various signaling cascade events involved in secondary metabolite production and stress tolerance. This chapter summarizes recent attempts and possible mechanisms of nanomaterial-based seed priming for mitigating abiotic stresses in crop plants.