Kinetin

About: Kinetin is a research topic. Over the lifetime, 7856 publications have been published within this topic receiving 135550 citations. The topic is also known as: Kinetin.

Cell culture of Taxus as a source of the antineoplastic drug taxol and related taxanes

Abstract: Callus cultures of Taxus cuspidata and Taxus canadensis were induced using different tissue explants including green and red arils, seed contents, young stems and needles. Callus derived from stem segments displayed the best growth in defined media. The culture medium was supplemented with reducing agents and phenolic-binding compounds to inhibit callus darkening and subsequent growth reduction. T. cuspidata explant growth was affected by different concentrations and ratios of 2,4-D and kinetin. Callus tissues of T. cuspidata were extracted for taxol after 2 months in culture and analysed by HPLC. The presence of taxol (0.020 +/- 0.005% of the extracted dry weight) was indicated based on retention time, U.V. spectra, peak purity as assessed by photo-diode array spectroscopy and compared with an authentic taxol standard, as well as by 1H-NMR analysis. Suspension cultures of T. cuspidata were established from the callus cultures, subsequently immobilized onto glass fiber mats, and maintained as immobilized cultures for 6 months. The immobilized cell cultures also produced taxol at levels up to 0.012 +/- 0.007% of the extracted dry weight.

Effect of AgNO3 and aminoethoxyvinylglycine on in vitro shoot and root organogenesis from seedling explants of recalcitrant Brassica genotypes.

Abstract: The presence of 1–10 μM aminoethoxyvinylglycine (AVG) or 5–30 μM AgNO3 markedly enhanced shoot regeneration from cotyledon and hypocotyl cultures of eight recalcitrant Brassica campestris and B. juncea genotypes tested. Expiants of B. campestris ssp. chinensis and ssp. parachinensis grown with a high AVG concentration (20 μM), regenerated poorly. All cytokinins tested were equally effective in promoting shoot formation, except that kinetin was inhibitory to shoot regeneration from hypocotyls of B. campestris ssp. pekinensis (cv. Wong Bok). Both AgNO3 and AVG had no effect on percent rooting and number of roots per rooted cutting of Wong Bok, White Sun and Leaf Heading, but AgNO3 was inhibitory to rooting of India Mustard. However, root elongation of all cuttings was markedly inhibited by AVG at concentrations of 5 and 10 μM.

Regulation of organogenesis in small explants of superficial tissue of Nicotiana tabacum L.

Abstract: Small explants composed of 3-6 layers of epidermal and subepidermal cells excised from floral branches of Nicotiana tabacum are capable of de novo organogenesis. Continuous mitoses without organogenesis, or mitoses followed by the formation of floral buds, vegetative buds or roots can be obtained by varying the auxin-cytokinin-sucrose ratio in the medium. The physiological stage of the floral branches, and light and darkness had also an influence on the de novo organogenesis. Best floral-bud formation was obtained when explants were taken from plants in which the terminal bud was in the green-fruit stage, and were cultured on a medium with indole-3-acetic acid and kinetin both at 10(-6) M and with 3% sucrose, in the light. For differentiation of vegetative buds, the optimal auxin/cytokinin ratio was one tenth of that for floral-bud formation, while the sucrose concentration was the same. Optimal conditions for root formation were: explants from plants in which the terminal bud carried a mature fruit; 10(-7) M kinetin, 10(-5) M indole-3-butyric acid, and 1% sucrose in the medium; and culture in darkness. The optimal medium for callus formation contained 5×10(-6)M 2,4-dichlorophenoxyacetic acid, 10(-7) M kinetin and 3% sucrose.

The effects of seed soaking with plant growth regulators on seedling vigor of wheat under salinity stress

Abstract: Effects of seed soaking with plant growth regulators (IAA, GA3, kinetin or prostart) on wheat (Triticum aestivum cv. Auqab-2000) emergence and seedling growth under normal (4 dS/cm) and saline (15 dS/cm) conditions were studied to determine their usefulness in increasing relative salt-tolerance. During emergence test, emergence percentage and mean emergence time (MET) were significantly affected by most of priming treatments, however, root and shoot length, fresh and dry weight of seedlings were significantly increased by 25 ppm kinetin followed by 1% prostart for 2 h treatments under both normal and saline conditions. All pre-sowing seed treatments decreased the electrolyte leakage of steep water as compared to that of non-primed seeds even after 12 h of soaking. Seed soaking with 25 ppm kinetin induced maximum decrease in electrolyte leakage while an increase in electrolyte leakage was observed by 25, 50 or 100 ppm IAA treatments. It is concluded that priming has reduced the severity of the effect of salinity but the amelioration was better due to 25 ppm kinetin and 1% prostart (2 h) treatments as these showed best results on seedling growth, fresh and dry weights under non-saline and saline conditions whereas seed soaking with IAA and GA3 were not effective in inducing salt tolerance under present experimental material and conditions.