This fourth edition of the successful textbook provides an updated introduction to the science and technology of seeds. It presents a straightforward exploration of the seed as a biological system, from its origin and examines the fundamentals of how seeds are produced, conditioned, evaluated, and distributed in modern agriculture. This edition has been thoroughly revised and contains new chapters on seed ecology and seed drying. Special care has been taken to incorporate new genetic testing procedures made possible by the biotechnology revolution that is occurring throughout agriculture. Principles of Seed Science and Technology, Fourth edition gives advanced undergraduate students the current state of the art and future trends in seed technology. Newcomers to the field will also benefit from this volume's straightforward style and in-depth treatment of the subject.