Chapter 5 - Mechanisms Involved in Stimulatory and Toxicity Effects of Nanomaterials on Seed Germination and Early Seedling Growth

Abstract

Recently, the application of nanomaterials has increased in modern agriculture, causing increased concentrations of nanomaterials in the environment. Because of the unique characteristics of nanomaterials, they can enter plant cells and interact with intracellular structures and affect seed germination, plant growth, cell structure, and function. Based on their concentration and type, engineered nanomaterials can have different biological impacts on various plant species. This can positively or negatively affect the photosynthesis, photochemical fluorescence, and quantum yield as well as the photosynthetic pigment status of the plants. That exposure of plants, especially plants that are food and or industrial crops, to various ENMs cause both up- and downregulation of primary metabolites, such as proteins and carbohydrates has been confirmed. The close relationship of ENMs activation and biosynthesis of the key enzymes is responsible for their potential capacity of changing the rate of primary metabolites. With the objective to ensure the safe use of nanomaterials in modern agriculture, detailed studies on the impact of various types of nanomaterials on seed germination, development of seedlings, and metabolism of valuable agricultural plant species are needed. This chapter surveys the reports of recent investigations of ENMs’ effects on seed germination, growth, and the mechanism involved in terrestrial plants.