The Book “The basics of Plant Breeding” has been prepared for Students of M.Sc. IV Sem (CBCS), Department of Botany, DDU Gorakhpur University, Gorakhpur. It is a part of paper III (Unit 2 and 3) some of its part has been recently introduced in course of CBCS system (in 2021). This book covers Unit 2 and 3 of paper III (M.Sc. IV Sem, Botany). In this book an attempt has been made to present the gist of the subject in a simple language and with suitable diagrams and it is hoped that this would be of some help to the students. The e-book contents are extracted/modified/compiled from various sources like research articles and freely available internet websites. It is organized for students to provide them the total content of unit 2 and 3 in one place. I acknowledge all the authors whose contents has been helpful in some or other ways in formation of this book. At last, but with deepest gratitude, I am thankful to the almighty God and deep, unfailing, supportive affection of my husband “Sri Abhai Kumar Srivastava” so that I was able to compile this work.