Topic
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.
Papers published on a yearly basis
Papers
More filters
TL;DR: Excised embrya and subsequently divided embrya of Podophyllum peltatum were cultured on the Murashige and Skoog medium supplemented with different growth regulators, because traditional methods of breaking seed dormancy failed.
Abstract: Excised embrya and subsequently divided embrya of Podophyllum peltatum were cultured on the Murashige and Skoog medium supplemented with different growth regulators, because traditional methods of breaking seed dormancy failed. The growth of excised embrya was stimulated by 1 or 0.1 mg dm-3gibberellic acid (GA3), 0.1 mg dm-3 GA3 + 0.2 mg dm-3 kinetin (kin), or 0.2mg dm-3 kin. GA3 (1 mg dm-3) showed the best effect; after 5 weeks the plantlets had 1.5 - 2 cm long cotyledons, 5 - 6 cm long roots, 88 % of embrya germinated and developed further. The addition of 0.5 mg dm-3 zeatin + 0.2 mg dm-3 naphtaleneacetic acid (NAA), 0.2 mg dm-3 NAA, and 1 mg dm-3 kinetin inhibited the growth of embrya. 1 mg dm-3 kinetin + 0.1 mg dm-3 NAA, 0.1 mg dm-3 zeatin and 0.2 mg dm-3 6-benzylaminopurine resulted in a compact appearance of plantlets and a lower germination rate. Divided embryo cultures produced plantlets via somatic embryogenesis which occurred only on the 2,4-dichlorophenoxyacetic acid containing media. The maturation of somatic embrya was observed on media without any auxin.
10 citations
TL;DR: In this paper, the results showed that all concentrations of the test material caused a decreasing mitotic index, genomic template stability (GTS), and soluble protein levels, but increased RAPDs profile changes (DNA damage) and DNA hypermethylation.
Abstract: In this research we aimed to evaluate DNA damage levels, DNA methylation, and protein and pytohormone level changes in corn seedlings (Zea mays L.) exposed to 5, 10, 20, and 40 mM concentrations of lead sulfate solution (PbSO4). The results showed that all concentrations of the test material caused a decreasing mitotic index, genomic template stability (GTS), and soluble protein levels, but increased RAPDs profile changes (DNA damage) and DNA hypermethylation. Moreover, in the HPLC (high-pressure liquid chromatography) analyses, it was also observed that Pb contamination caused a decrease in the growth-promoting hormones including gibberellic acid (GA), zeatin (ZA), and indole acetic acid (IAA) levels, in contrast to increasing the absisic acid (ABA) level. The results of this experiment have clearly shown that Pb has a significant impact on the epigenetic mechanisms as well as its genotoxic effects. Some of phytohormone decreases (GA, ZA and IAA) and especially increasing ABA levels under Pb stress may be a part of the defense system against stress.
10 citations
TL;DR: In this system, the time required for shoot regeneration was 2 weeks, which was shorter by two weeks than that of previous reports, and the regeneration system did not involve the callus phase and thus was less prone to somaclonal variation.
Abstract: Plant regeneration from 9 clones ofPopulus tremula representing diverse genotypes originated from Turkey, has been studied in different media, such as Murashige and Skoog’s Medium (MS), Aspen Culture Medium (ACM) and Woody Plant Medium (WPM) with appropriate supplements of growth regulators. Regeneration efficiency on WPM containing 1 mg/l zeatin using stem explantsin vitro, was higher than on MS and ACM. In this system, the time required for shoot regeneration was 2 weeks, which was shorter by two weeks than that of previous reports. A strong genotype dependence was observed among the tested nine clones. The regeneration system, we describe here, did not involve the callus phase and thus was less prone to somaclonal variation. When adventitious microshoots were cultured on WPM supplemented with 0.5 mg/l or 2 mg/l indole-3-butyric acid (IBA), root formation was obtained after 1 week of culture. Adaptation of regenerated plantletsin vivo was 100%. This system for micropropagation ofPopulus tremula is expected to be suitable for studies on transformation of genes involved in lignin biosynthesis via modification of lignin content.
10 citations
TL;DR: It would appear as if the buds and sprouts do not synthesize cytokinin, and initial bud growth may be dependent on the supply of cytokinins within the mother tubers, while the increase in the sprouts could be the result of root development at their basal ends.
Abstract: In an attempt to determine whether potato buds synthesize cytokinins, tubers and potato pieces were subjected to conditions which both retard and accelerate bud development. Cytokinin activity was recorded in the tubers and sprouts under different experimental conditions. Most of the com pounds detected had chromatographic properties resembling those of zeatin, zeatin riboside, and zeatin glucoside. It would appear as if the buds and sprouts do not synthesize cytokinins. Initial bud growth may be dependent on the supply of cytokinins within the mother tubers, while the increase in the sprouts could be the result of root development at their basal ends.
10 citations
TL;DR: Cytokinin-like activity at the infection site/green islands increased with the period of incubation of the host as compared to the surrounding tissue or tissue under water drops, by virtue of which carbohydrates accumulate at these sites ensuring a continuous supply to the growing pathogen.
Abstract: Significant stimulation of the number of appressoria, penetration and colonization by conidia ofHelminthosporium carbonum occurred on decolorized maize leaves when exogenous carbohydrates and leaf leachates were added. Germination and germ tube length, however, did not exhibit appreciable differences on decolorized or non-decolorized maize leaves. Lower germination was recorded by leached conidia on decolorized leaves; while appressoria, penetration and colonization were absent. Addition of exogenous nutrients (sucrose>leaf leachates>yeast extract>glucose) enabled conidia to accomplish appressoria, penetration and colonization. Optimum levels for various nutrients observed were 2% (w/v) sucrose/glucose or 0.1% (w/v) yeast extract. Higher concentrations inhibited the infection stages of the pathogen. Depletion of host carbohydrates from green islands/infection sites adversely affect appressoria formation, penetration and colonization; and the loss of carbohydrates from the spore affects germination. Cytokinin-like activity at the infection site/green islands increased with the period of incubation of the host as compared to the surrounding tissue or tissue under water drops. The culture filtrate extracts ofH. carbonum recorded cytokinin-like activity which increased with growth of the fungus. TLC (thin layer chromatography) of cytokinin-like substances (tissue extract and culture filtrate) revealed major activity was confined to Rf zones 0.6 to 0.8 which co-chromatographed with zeatin and zeatin riboside. These substances increase at infection sites by virtue of which carbohydrates accumulate at these sites ensuring a continuous supply to the growing pathogen.
10 citations