This book looks at the interaction between plants and nanomaterials/nanocomposites, and their effects ecology, the food chain and human health. It focuses on nanomaterials/nanocomposites phytotoxicity, which is an important precondition to promote the application of nanotechnology and to avoid the potential ecological risks. It describes the influencing factors of nanotoxicity of nanomaterials and the mechanisms of these toxic effects and defense mechanisms in plants. The chapters in this book are written by internationally renowned researchers and professionals and provides exciting and remarkable information (on the above-mentioned topics) to the scientist, researcher and student working field of plant biology, agricultural science, nanobiotechnology, plant biochemistry, plant physiology, plant biotechnology and many other interdisciplinary subjects.