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Two field experiments were carried out to investigate the role of seed soaking with spermine (Spm, 10 mg/l) and the foliar application of mineral nutrients (K and Zn), alone or in combination, in improving the tolerance of sunflower ( Helianthus annuus L.) to calcareous and salinity stress conditions. Both the individual treatments and the interaction increased the stem diameter, shoot fresh and dry weights, yield, yield components and oil yield, as well as the concentrations of K, Ca, P and Zn and the K/Na ratio, whereas they decreased the Na concentration in the two growing seasons. The best results were obtained with the K+Zn+Spm treatment in both seasons.It could be concluded that seed soaking with Spm and the foliar application of K and Zn might alleviate the harmful effects of calcareous and salinity stress and enhance the ability of sunflower plants to tolerate these adverse conditions.

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abundant PAs in plants including diamine putrescine (Put), triamine spermidine (Spd), and tetraamine spermine (Spm) are small ubiquitous polycationic nitrogenous compounds, which are present in the free forms, soluble conjugated to small molecules, and

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spermine reveals enhanced anabolic and nitrogen-carbon interactions . Plant Physiol. 142 : 1759 – 1770 . McKenzie , H.A. , Wallace , H.S. 1954 . The Kjeldahl determination

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235 269 Feuerstein, B. G., Pattabiraman, N., Marton, L. C. (1989) Molecular dynamics of spermine-DNA interactions: sequence specifity and DNA bending for a simple ligand

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Ha, H. C., Sirisoma, N. S., Kuppusamy, P., Zweiler, J. L., Woster, P. M., Casero, R. A. Jr. (1998): The natural polyamine spermine functions directly as a free scavenger. PNAS , 95 , 11140–11145. Casero R. A

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1620 1635 Durmus N., Kadioğlu, A. (2005) Spermine and putrescine enhance oxidative stress tolerance in maize leaves. Acta Physi. Plant. 27, 515

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The biologically active amines of grapes, aszú-grapes, aszú-wines of Tokaj region were analysed to study the effect of Botrytis cinerea on the grapes. It was established that grapes contained mainly spermidine, putrescine and spermine, however, in the aszú-grapes new amine compounds such as agmatine, phenethylamine, butylamine and pentylamine isomers appeared. The spermine content showed an increase in all aszú-grape varieties compared to the grapes. During winemaking processes, spermine disappeared and the concentration of tyramine increased in the aszú-wines. The concentration of spermidine decreased during the ageing of the product. The ratio of tyramine and amine content of the samples were found to be within a limited interval.

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Morphological and biochemical changes in plant cells are known as important events for adaptation to stress. In this study, in Ctenanthe setosa leaves to which polyamines were applied during drought stress, changes in the activity of peroxidase, reducing sugar, proline and soluble protein levels were investigated. The three common polyamines, putrescine, spermidine and spermine were exogenously treated through the leaves. The polyamines were sprayed onto the leaves at 5×10−5 M. In the leaves to which polyamines were applied the peroxidase activity decreased, soluble protein increased. Also, it was determined that putrescine and spermidine caused an increase in the amount of proline and in reducing sugar. However, increase was not observed in the leaves to which spermine was applied. In addition, we observed an increase in the activity of peroxidase, proline and reducing sugar levels, and a decrease in soluble protein level in the control ones and the leaves to which polyamines were applied during drought stress. As a result, the effect of polyamine on leaf rolling may be explained through the contribution to osmotic adjustment of the increase in proline, reducing sugar and soluble protein contents.

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The effectiveness of Cu 2+ accumulation was investigated in three wheat cultivars with different copper sensitivity ( Triticum aestivum cv. GK Tiszatáj, GK Kata and GK Öthalom). Supraoptimal Cu 2+ concentrations result in toxicity symptoms in the sensitive genotype and increase the production of the stress hormone, ethylene both in the leaves and root tissues of wheat seedlings. The sensitive cultivar, cv. Öthalom produced less ethylene than the tolerant genotypes (cvs Tiszatáj and Kata) in the roots whether the ethylene measurements were done over the 6-h period after Cu 2+ exposure. Levels of 1-aminocyclopropane-1-carboxylic acid (ACC), the immediate precursor of ethylene, did not change characteristically during this period in either the tolerant or sensitive seedlings. The biosynthesis of ethylene has a common intermediate, S-adenosylmethionine (SAM) with the synthesis of the polyamine spermidine and 2-deoxymugineic acid, a Fe 3+ -solubilizing and transporting wheat phytosiderophore. These chelating substances also mediate the transport of different bivalent cations, such as Cu 2+ . The biosynthetic pathways of ethylene and polyamines, spermidine and spermine may compete for SAM with the phytosiderophore synthesis. Simultaneous inhibition of SAM decarboxylase by 0.5 M methylglyoxal bis (guanylhydrazone) (MGBG), and 1-aminocyclopropane-1-carboxylic acid synthase by 10 μM (2-aminoethoxy-vinyl)glycine (AVG), significantly increased the Cu 2+ accumulation in root tissues of the wheat cultivars independently of their sensitivities. MGBG alone resulted in an enhanced copper content but AVG proved to be ineffective. This suggests that the amount of SAM allocated for polyamine formation may limit the phytosiderophore synthesis or spermidine (spermine) in itself may control the uptake of Cu 2+ .

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Authors: Irena Baranowska, Piotr Markowski, Andrzej Wilczek, Magdalena Szostek and Marlena Stadniczuk

Simple, rapid and selective NP-TLC and RP-TLC methods are described for analysis of l -arginine, its primary metabolites (l -citrulline, l -glutamine, l -ornithine, asymmetric N G , N G -dimethyl-l -arginine, symmetric N G , N G ′-dimethyl-l -arginine, N G -nitro-l -arginine, N G -hydroxy-l -arginine, N G -monomethyl-l -arginine, agmatine, putrescine, spermidine, spermine, and creatine) and selected drugs (dexamethasone, prednisolone, furosemide, vancomycin, amikacin, fluconazole, digoxin, captopril, dipyrone, metoprolol, and sildenafil), in different therapeutic groups, in model solutions and in spiked human urine. NP-TLC and RP-TLC methods have been used to study the retention of the substances. A variety of mobile phase systems were evaluated for separation of ARG and its metabolites — methanol-50% acetic acid 3:1 ( v/v ) on silica gel and 5% acetic acid-methanol-acetonitrile 50:35:15 ( v/v ) on RP-18 — and for separation of the drugs — acetonitrile-water 2:3 ( v/v ) on silica gel. The effects on selectivity of the polar modifier of mobile phases were also studied.

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