The study of genes, variation and heredity explored under the fields of genetics and genomics has wide applications in crop science. Crop breeding is used for improving the quality of food for humans and animals. It is accomplished using techniques of classical plant breeding and complex molecular techniques. New varieties of crops that are more productive, have higher climatic adaptability and disease resistance are being developed to optimize agricultural productivity. Modern biotechnological tools of marker-assisted selection, double haploids, reverse breeding and genetic modification are evolving methodologies of crop breeding. This book is a compilation of chapters that discuss the most vital concepts and emerging trends in the science of crop breeding, especially from the perspective of genetic and genomic studies. Multiple approaches, evaluations and methodologies have been included in this book to cover the recent advances in this field. It will be beneficial to experts and students seeking detailed information in this domain.