Nowadays, viral diseases are considered one of the most serious economical problems to be solved worldwide. Unlike other pathogens and pests, viruses cannot be eradicated chemically. Induction of plant s natural defenses, such as systemic acquired resistance (SAR), is the way for management of plant viral diseases. This induction of resistance occurs through changes of some physiological mechanisms and controlling enzyme activities. Understanding the mechanisms responsible for these physiological alterations, which developed during virus infection or resistance induction, are the major current challenges in the study of plant viral disease. In the present time, host induced resistance is required to minimize the overloading economical problems occurred due to viral disease outbreaks. The findings presented in this book will provide new insights into the epidemiological benefits of commercial induced resistance against virus disease. These features have significant implications inenvironmental safety assessment.