The cause of the permanent wilted state of some mutant tomato (Lycopersicon esculentum Mill.) strains has been shown to be an insufficiency of abscisic acid (ABA). The mutants contain larger than normal amounts of a C10 dienoic dicarboxylic acid (2,7-dimethylocta-2,4-dienoic acid (ODA) whose structure suggests that it is the central residue of a carotenoid from which two potential carbon skeletons of ABA have been removed. When tomato plants were supplied with 2H2O for 6 days the ABA was found to be labelled with up to 11 deuterium atoms while the ODA was unlabelled. ODA, therefore, cannot be a by-product of the biosynthesis of ABA.
- abscisic acid
- dimethyloctadienedioic acid