little is known about the levels and physiological role of endogenous abscisic acid (aba) during after-ripening and germination. genetic variants for aba content were investigated to account for the role of aba in the persistence of seed dormancy. in this study, genotypic variation in aba contents at zadok’s growth stage 92 (zgs 92), temporal changes in aba during two physiological stages (...

trichosanthes kirilowii, an important economic plant in china, is sensitive to chilling. to investigate the effect of abscisic acid (aba) treatment on the chilling tolerance of trichosanthes kirilowii maxim, different concentrations of aba were sprayed on trichosanthes kirilowii leaves and the resulting catalase (cat) and superoxide dismutase (sod) activities and the malondialdehyde (mda) conte...

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...

Nitrate has profound effects on plant growth and development. Adequate nitrate levels inhibit lateral root growth, as the plant senses it has all the nitrate it needs. Conversely, a patch of nitrate in poor soil triggers the initiation or elongation of lateral roots, a remarkably plastic process that requires the interplay of nitrate sensing and auxin signaling pathways (Krouk et al., 2010). Th...

Changes in gene expression produced by the application of (+)-abscisic acid (ABA) to Arabidopsis thaliana plants were compared with changes produced by the ABA structural analogs (-)-ABA, (+)-8'-acetylene ABA and (-)-2',3'-dihydroacetylenic abscisyl alcohol. The maximum expression of many rapidly (+)-ABA-induced genes occurred prior to peak hormone accumulation, suggesting negative feedback reg...

A protein designated ABAP1 and encoded by a novel gene (GenBank accession number AF127388) was purified and shown to specifically bind abscisic acid (ABA). ABAP1 protein is a 472-amino acid polypeptide containing a WW protein interaction domain and is induced by ABA in barley aleurone layers. Polyclonal antiidiotypic antibodies (AB2) cross-reacted with purified ABAP1 and with a corresponding 52...

The plant hormone abscisic acid (ABA) accumulates in plant tissues which experience water deficit (stress ABA). This study analysed its accumulation as a function of both synthesis and catabolism in maize tissues. By following the disappearance of the stress ABA when ABA synthesis was blocked by nordihydroguaiaretic acid (NDGA), the rate of the catabolism of stress ABA was determined. When comp...

Abscisic acid (ABA) plays a key role in plant growth and development. The effect of ABA in plants mainly depends on its concentration, which is determined by a balance between biosynthesis and catabolism of ABA. In this study, we characterize a unique UDP-glucosyltransferase (UGT), UGT71C5, which plays an important role in ABA homeostasis by glucosylating ABA to abscisic acid -: glucose ester (...