Zeatin

About: Zeatin is a research topic. Over the lifetime, 2467 publications have been published within this topic receiving 64092 citations. The topic is also known as: Zeatin & (E/Z)-zeatin.

Effect of increased irradiance on the hormone content, water relations, and leaf elongation in wheat seedlings

Abstract: In wheat (Triticum durum Desf., cv. Bezenchukskaya 139) seedlings, an increase in irradiance from 20 to 400 μmol/(m2 s) PAR enhanced transpiration and increased stomatal conductance by three times on the background of reduced relative water content (RWC). After this treatment, leaves quickly ceased to grow and became even shrunk later. In 40 or 50 min, leaf growth was resumed. At this period, we observed an increase in hydraulic conductivity and RWC and also in leaf extensibility. As soon as 10 min after treatment, some changes in hormone content were noted. In the zones of leaf growth and its mature part, zeatin and zeatin riboside were accumulated, whereas ABA accumulation was observed in the zone of leaf growth and in the roots. The results obtained indicate that leaf expansion at increased irradiance was related to changes in cell-wall extensibility and hydraulic conductivity. The first effect could be due to cytokinin accumulation, whereas the second one, to ABA accumulation.

In vitro propagation of Moroccan carob (Ceratonia siliqua L.)

Abstract: An efficient and rapid method is described for the in vitro propagation of the Moroccan carob (Ceratonia siliqua L.) from nodal segments obtained by in vitro germination using MS (Murashige and Skoog) medium. Various concentrations of different growth regulators were examined for the multiplication and rooting phases. In shoot multiplication, the best effects of cytokinins were obtained with 2 mg/l of zeatin and 2 mg/l of BAP (6-benzylaminopurine). The best effect of the combination of auxins and BAP was obtained with 0.5 mg/l of BAP and 0.5 mg/l of each auxin IBA (indole-3-butyric acid), NAA (2-naphthaleneacetic acid), and IAA (indole-3-acetic acid)). Nevertheless, the combination of 1.5 mg/l of BAP, 0.5 mg/l of IBA and 0.5 mg/l of GA3 (gibberellic acid) induced shoot multiplication and also provided rooting of shoots. Microshoots obtained from in vitro multiplication were best rotted in half-strength MS medium containing 2 mg/l of IBA. Acclimatization of vitroplantlets was relatively successful, 5 of plantlets transferred to potting mixture survived after 2 months.

Comparison of Zeatin Indoleacetate with Zeatin and Indoleacetic Acid in the Tobacco Bioassay

Abstract: Zeatin indole-3-acetate, 6-[4-(indole-3-acetoxy)-3-methyl-trans-2-butenylamino]purine, is at least as effective as zeatin on a molar basis in satisfying the cytokinin requirement for growth and bud formation in tobacco bioassays It is less effective than indole-3-acetic acid and is needed as a variable function of the cytokinin concentration for satisfying the optimal requirement of an auxin Comparisons of the types of growth and yield of tissue obtained with serial concentration of the ester and with equimolar mixtures of its free base and acid indicate that the relative requirement for auxin changes with the concentration of cytokinin and is related to the types of callus growth and differentiation which occur The results also suggest that the ester serves as a source of auxin only after modification, presumably by hydrolysis to indoleacetic acid