TABLE OF CONTENTS 



PAGE 



ACKNOWLEDGEMENTS 1 1 1 



ABSTRACT v1 1 



INTRODUCTION 1 



LITERATURE REVIEW 4 



Gibberellic Acid 4 



Hi story 4 



Chemical and Physical Characteristics 5 



Relative Potency of Gibberellins 8 



Toxicology 9 



Biosynthesis and Metabolism 10 



Sites of Synthesis 11 



Transport 12 



Mode of Action 13 



Interaction with Other Plant Growth Substances 20 



Commercial Applications 22 



Effects on Waterhyaci nths 24 



2,4-Dichlorophenoxyacetic Acid 25 



History 25 



Physical and Chemical Characteristics 27 



Toxicology 28 



Persistence in the Environment 29 



Mode of Action - 31 



Translocation 35 



Metabolism by Plants 36 



Efficacy of 2,4-D on Waterhyaci nths 37 



PART 1. SMALL PLOT EVALUATIONS 40 



Introduction 40 



Materi al s and Methods 41 



Results and Discussion 43 



Summary 53 



PART 2. TRANSLOCATION EVALUATIONS 54 



Introduction 54 



Materi al s and Methods 54 



Results and Discussion 57 



Summary 70 



