effects of gibberellic acid (ga) and abscisic acid (aba) on dormant and after-ripened wheat seed, cultivar rl4137, were studied. the aim of the study was to evaluate the effects of seed after-ripening in comparison with gibberellin application on breaking of seed dormancy. moreover, the effect of abscisic acid on dormancy induction was also evaluated. acid and alkaline posphatase activity of se...

Of nine plant growth regulators (indoleacetic acid, 1-naphthalene acetic acid, gibberellic acid, giberellin 4/7, 6-benzylaminopurine, 6-furfurylaminopurine, abscisic acid, and 1-aminocyclopropane carboxylic acid) tested, only 6-benzylaminopurine and abscisic acid affected (14)C-photosynthate unloading from excised seed coats of Phaseolus vulgaris L. Unloading, in the presence of KCl, was stimul...

Potamogeton nodosus tubers produce floating-type instead of submersed-type leaves when exposed to 10(-5) molar synthetic abscisic acid. Abscisic acid-induced leaves have stomata on upper leaf surfaces and higher width/length ratios than controls. These effects are wholly or partially overcome by simultaneous exposure to abscisic acid combined with gibberellic acid, kinetin, or benzyladenine.

The effect of the abiotic stress hormone abscisic acid on plant disease resistance is a neglected field of research. With few exceptions, abscisic acid has been considered a negative regulator of disease resistance. This negative effect appears to be due to the interference of abscisic acid with biotic stress signaling that is regulated by salicylic acid, jasmonic acid and ethylene, and to an a...

Short and high-yielding syntheses of enantiomerically pure (S)-(+) and (R)-(-)-abscisic acid are described. The syntheses proceed through key intermediates that preferentially recrystallise as single diastereoisomers for each enantiomer. This route allows the preparation of either enantiomer of abscisic acid in ca. 30% overall yield, and as demonstrated, gives access to an enantiomerically pure...

This paper describes a new method for qualitative and quantitative assay of abscisic acid and other acidic plant hormones, such as indoleacetic acid and the gibberellins, by the gas-liquid chromatography of their trimethylsilyl derivatives. Interfering substances in plant extracts were largely removed by preliminary column chromatography with carbon-celite and elution of the abscisic acid with ...

We previously demonstrated that the oxylipin 12-oxo-phytodienoic acid (OPDA) acts along with abscisic acid to regulate seed germination in Arabidopsis thaliana, but the mechanistic details of this synergistic interaction remain to be elucidated. Here, we show that OPDA acts through the germination inhibition effects of abscisic acid, the abscisic acid-sensing ABI5 protein, and the gibberellin-s...

We found that appropriate treatment with a highly potent and long-lasting abscisic acid analog enhanced the tissue expansion of scutellum during early seedling development of rice, accompanied by increases of protein and starch accumulation in the tissue. A comparative display of the protein expression patterns in the abscisic acid analog-treated and non-treated tissues on two dimensional gel e...

Abscisic acid hastened senescence of carnation flowers and this was preceded by stimulation of accelerated ethylene production. Carbon dioxide delayed the onset of autocatalytic ethylene production in flowers regardless of treatment with abscisic acid. Flowers exhibited a low and transient climacteric of ethylene production without wilting while in 4% carbon dioxide and underwent accelerated et...

The concentrations of abscisic acid in Grand Rapids lettuce (Lactuca sativa L.) seeds imbibed under conditions which promote or inhibit germination were determined by electron capture-gas chromatography. The concentration of abscisic acid in dry seeds was 12 to 14 nanograms per 100 milligrams. During 24-hour imbibition, the abscisic acid content diminished more rapidly during conditions which a...