Experiments with Arabidopsis mutants and sensitive and tolerant pairs in several other species have elucidated the molecular basis of plant ozone sensitivity and ozone lesion development. They have indicated an important role for hormonal signalling in determining the outcome of ozone challenge at the cellular level. The reactive oxygen species (ROS) from ozone degradation can cause either dire...

L.-S.P. Tran and S. Pal (eds.), Phytohormones: A Window to Metabolism, Signaling and Biotechnological Applications, DOI 10.1007/978-1-4939-0491-4_2, © Springer Science+Business Media New York 2014 Abstract Abscisic acid (ABA) is an important phytohormone regulating various physiological aspects in plants such as seed maturation, dormancy, seedling growth, and stomatal behaviour. In this chapter...

Effects of supplying K2O at 0, 12, 24 and 36 g m 2 soils on distribution of photosynthates (carbohydrates produced by photosynthesis) were studied in plants of Ipomoea batatas Lam (Beijing 553). Storage roots yield, photosynthate distribution, sucrose synthase and insoluble acid invertase activities, as well as abscisic acid content in storage roots were determined. The storage root yield firs...

The phytohormone abscisic acid (ABA) is crucial for plant growth and adaptive responses to various stress conditions. Plants continuously adjust the ABA level to meet physiological needs, but how ABA homeostasis occurs is not fully understood. This study provides evidence that UGT71B6, an ABA uridine diphosphate glucosyltransferase (UGT), and its two closely related homologs, UGT71B7 and UGT71B...

It has previously been shown that the abscisic acid (ABA)-deficient flacca and sitiens mutants of tomato are impaired in ABA-aldehyde oxidation and accumulate trans-ABA-alcohol as a result of the biosynthetic block (IB Taylor, RST Linforth, RJ Al-Naieb, WR Bowman, BA Marples [1988] Plant Cell Environ 11: 739-745). Here we report that the flacca and sitiens mutants accumulate trans-ABA and trans...

We report here the synthesis and biological activity of a new persistent abscisic acid (ABA) analog, 8[prime]-methylene ABA. This ABA analog has one additional carbon atom attached through a double bond to the 8[prime]-carbon of the ABA molecule. (+)-8[prime]-Methylene ABA is more active than the natural hormone (+)-ABA in inhibiting germination of cress seed and excised wheat embryos, in reduc...