Metabolism and Physiology of Abscisic Acid

INTRODUCTION 440 TECHNIQUES 440 Quantification of ABA . ...... . . ...... . 440 Separation of Sand R-Abscisic Acid 441 Stable Isotopes and Mass Spectrometry 442 Extraction and Quantification of Xanthoxin 442 METABOLISM 443 Biosynthesis in Fungi 443 Biosynthesis in Higher Plants 444 Catabolism . . . . . . . . . .. . .... . . . . . . . . . . . . . . .. . . ..... . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... ..... . . . . . . . 453 Compartmentation 454 EFFECTS OF ABSCISIC ACID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456 Physiological Responses 456 Biochemical Responses..... . ...... . 461 CONCLUDING REMARKS 463