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.

In vitro Plant Regeneration System for Two Middle East Cultivars of Chickpea (Cicer arietinum L.)

Abstract: This study surveyed a rapid, efficient and reproducible protocol for in vitro shoot regeneration and rooting of two Middle East chickpea cultivars (Balila and Wady). Organogenic ability of various explants (decapitated embryo axes, fragments of embryo axes, fragments of embryo axes with basal part of cotyledons, entire and half of cotyledons) was tested on MS media containing different concentrations and nature of cytokinins (BAP and zeatin) or compound with cytokinin-like activity (TDZ). The highest level of shoot regeneration was achieved in Balila genotype using embryo axes fragments including the basal part of cotyledon on medium with 0.25 mg/L BAP. Higher BAP concentrations than 0.25 mg/L for Balila and 0.5 mg/L for Wady caused a decrease of shoot regeneration. On MS media supplemented with zeatin (1, 3 and 5 mg/L) and thidiazuron (1, 3 and 5 mg/L), the highest level of shoot differentiation was obtained from calli derived from fragments of embryo axes. Organogenic ability of calli from Wady genotype was enhanced by increasing zeatin and TDZ concentrations, up to 5 mg/L. Conversely, a progressive decrease of shoot frequency for Balila and root development for both genotypes, were observed with increasing concentrations of BAP, zeatin and TDZ.

Liquid culture and transformation of hinoki cypress ( Chamaecyparis obtusa Sieb. et Zucc.)

Abstract: Hinoki cypress (Chamaecyparis obtusa) is one of the most important timber resource forest trees in Japan. Because seed production from a seed orchard of hinoki cypress is not constant every year, micropropagation from a limited amount of material is useful. Up to now, the conventional tissue culture method using solid medium has been used. Here a new method using liquid culture in tubes rotated vertically is described. Shoot primordium of hinoki cypress was inoculated in Campbell and Durzan’s (CD) liquid medium containing different cytokinins (6-benzylaminopurine (BAP), Zeatin, thidiazurone (TDZ)), and the container tubes were rotated vertically around the axis at 2 times / min. Culture room temperature was 25°C and light condition was 16 h photoperiod per day of fluorescent lamps. Zeatin at 1μM concentration was the best for maintaining the shoot primordium production and TDZ induced callus on the surface of the shoot primordia. After shoot primordium multiplication in the liquid culture, they were transplanted to agar medium for shoot elongation. A high concentration of agar (up to 16 g/L) or AVF (anti vitrification factor from Dr. Nairn, 1995) was effective to prevent vitrification of the shoots. Transformation of shoot primordium was done using particle bombardment with vectors containingβ-glucuronidase (GUS) gene or herbicide resistance gene (bar). Positive result for transient transformation was observed with the histo-chemical study for transformation with GUS. Integration of a useful herbicidebar gene into the shoot primordium culture system was also tried and stably transformed plants were obtained. This is the first report of stable transformation of Japanese conifer using practically useful gene.

Naturally occurring cytokinins in aonla (emblica officinalis gaertn.) fruit

Abstract: SUMMARY The fruit of Emblica officinalis remains dormant for a period of 31/2 months after setting. Studies on endogenous cytokinin activity of the fruit including exogenous applications of cytokinin suggest that dormancy may not be due to cytokinin deficiency. Fruit making rapid growth following dormancy was found to contain six cytokinin-like substances, active in the soybean cotyledon callus test. Three of these were tentatively identified as zeatin, zeatin riboside and zeatin nucleotide. The authors are grateful to Dr K. Koshimitzu, Kyoto University, Japan, for the gift of an authentic sample of dihydrozeatin and to the Council of Scientific and Industrial Research, New Delhi, for the award of Senior Research Fellowship to one of them (S.R.).

Shoot proliferation of Euphorbia fulgens in vitro affected by medium components

Abstract: Effects of trans-zeatin, sucrose, myo-inositol, and medium pH on shoot proliferation of Euphorbia fulgens Karw, ex Klostch were studied in vitro. Maximum shoot production occurred on media supplemented with 5 μM zeatin, but maximun shoot length with 5 to 15 μM. Shoot production increased with sucrose concentration, and was maximal at 131.5 mM. myo-Inositol concentration up to 0.6 mM did not have a significant effect on shoot production, but > 1.1 mM reduced it. The optimal medium pH was 5.3 for shoot proliferation, but lower pH values stimulated shoot growth (...)