CONTENTS

THE THEORETICAL PRINCIPLES OF VERNALIZATION 9
  Introduction 9
  The History of the Problem of Vernalization 13
  The Development of a Seed Plant and Its Growth Are Not Identical Phenomena 27
  Phases in the Development of Plants 33
  Significance of the Individual Factors in the Set of External Conditions Plants Need for Traversing the Vernalization Phase 41
  Sequence of Phases in the Development of Plants 45
  Phasic Changes in Plants Take Place at the Growing Points of the Stems 51
  The Localization of Phasic Changes 58
  Brief Conclusions Concerning the Phasic Development of Annual Seed Plants 62
PLANT BREEDING AND THE THEORY OF PHASIC DEVELOPMENT OF PLANTS 65
The Individual Development of the Hereditary Foundation of Plants 65
  The Choice of Parental Pairs, the Law of Dominance, and the Nature of Heterosis as Expressed in Duration of Vegetative Periods 78
  Practical Methods of Selection Work Based on the Theory of Development   96