This book focuses on the evolution of plant viruses, their molecular classification, epidemics and management, covering topics relating to evolutionary mechanisms, viral ecology and emergence, appropriate analysis methods, and the role of evolution in taxonomy. The currently emerging virus species are increasingly becoming a threat to our way of life, both economically and physically. Plant viruses are particularly significant as they affect our food supply and are capable of rapidly spreading to new plant species. In basic research, plant viruses have become useful models to analyze the molecular biology of plant gene regulation and cell-cell communication. The small size of DNA genome of viruses possesses minimal coding capacity and replicates in the host cell nucleus with the help of host plant cellular machinery. Thus, studying virus cellular processes provides a good basis for explaining DNA replication, transcription, mRNA processing, protein expression and gene silencing in plants. A better understanding of these cellular processes will help us design antiviral strategies for plants. The book provides in-depth information on plant virus gene interactions with hosts, localization and expression and the latest advances in our understanding of plant virus evolution, their responses and crop improvement. Combining characterization of plant viruses and disease management and presenting them together makes it easy to compare all aspects of resistance, tolerance and management strategies. As such, it is a useful resource for molecular biologists and plant virologists alike.