As a part of agriculture, man started rearing plants and animals to meet his requirements. This is when humans started to learn how to influence the process of natural evolution so as to breed plant or animals. Slowly and gradually, this process of expedited evolution, through selection and cultivation of plants, acquired the form of a routine endeavour—what we today call 'plant breeding'. In this, heredity, which refers to the passage of various characteristic features from the main plant (the parent) to the plantlets (the progeny), plays an important role. The effects of heredity had been apparent to early man and he had taken advantage of them ever since the advent of agriculture. Various methods have evolved in plant breeding. This book has been intended as a manual for students of this subject.