The dynamic and ever-expanding knowledge of environmental stresses and their effects on plants and crops has resulted in the compilation of a large volume of information since the third edition of the Handbook of Plant and Crop Stress was prepared and presented to scientists and professionals. This fact necessitated that this unique comprehensive source of information be revised again and all the new findings in this field be included in the new edition of this book. Like the first, second, and third editions, the new edition of the Handbook of Plant and Crop Stress is also a unique, most comprehensive, and complete collection of the issues of stress imposed on plants/crops. More than 80% of the materials of the new edition of the Handbook of Plant and Crop Stress are entirely new, and these are included in this volume under new titles. The other 20% of the old materials have been updated. Therefore, overall, over 90% of this book is new, and it appears that a totally new volume has emerged.