The domain of agricultural science which uses scientific techniques and tools for the modification of living organisms like plants, animals and microorganisms, is referred to as agricultural biotechnology. Some of the tools and techniques used in this field are genetic engineering, molecular markers, vaccines, molecular diagnostics and tissue culture. One of its major applications is in the field of crop science where desired characteristics are transferred from a particular species of crop to a different species. These desired traits could be related to flavor, resistance to diseases and pests, flower color, size of harvested products and growth rate. The important crop modification techniques include traditional breeding, mutagenesis, RNA interference, transgenics, genome editing and polyploidy. This book is a valuable compilation of topics, ranging from the basic to the most complex theories and principles in the field of agricultural biotechnology. It aims to shed light on some of the unexplored aspects of this field. This textbook will provide comprehensive knowledge to the readers.