Effect of osmotic stress and sodium nitroprusside pretreatment on proline metabolism of wheat seedlings
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Effect of osmotic stress and sodium nitroprusside (SNP, NO donor) pretreatment on growth and proline metabolism of wheat seedlings was investigated. Polyethylene glycol 6000 treatment for 2, 4 and 6 d could be termed as mild, moderate and severe stress, respectively, according to decrease in the relative water content. Severe osmotic stress significantly decreased the growth and photochemical efficiency, and increased proline content due to activation of its synthesis. 0.2 mM SNP pretreatment enhanced growth of wheat seedlings, increased variable to maximum fluorescence ratio (Fv/Fm) and fluorescence yield, while decreased proline content. However, 2 mM SNP retarded the seedlings growth and chlorophyll a fluorescence, and increased proline accumulation. Our results showed that NO might be involved in the regulation of osmotic stress in a concentration-dependent manner.
Additional key wordschlorophyll a fluorescence exogenous nitric oxide Triticum aestivum L
relative water content
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- Dallier, K.A., Stewart, C.R.: Effect of exogenous abscisic acid on proline dehydrogenase activity in maize (Zea mays L.).-Plant Physiol. 99: 762–764, 1992.Google Scholar
- Igarashi, Y., Yoshiba, Y., Sanada, Y., Yamaguchi-Shinozaki, K., Wada, K., Shinozaki, K.: Characterization of the gene for Δ1-pyrronline-5-carboxylate synthetase and correlation between the expression of the gene and salt tolerance in Oryza sativa L.-Plant mol. Biol. 33: 857–865, 1997.PubMedCrossRefGoogle Scholar
- Ruan, H., Shen, W., Xu, L.: Nitric oxide involved in the abscisic acid induced proline accumulation in wheat seedling leaves under salt stress.-Acta bot. sin. 46: 1307–1315, 2004.Google Scholar
- Schreiber, U., Bilger, W., Neubauer, C.: Chlorophyll fluorescence as a nonintrusive indicator for rapid assessment of in vivo photosynthesis.-In: Schulze, E.D., Martyn, M., Caldwell, M.M. (ed.): Ecophysiology of Photosynthesis. Pp. 49–70, Springer-Verlag, Berlin 1994.Google Scholar
- Tu, J., Shen, W., Xu, L.: Regulation of nitric acid on the aging process of wheat leaves.-Acta bot. sin. 45: 1055–1062, 2003.Google Scholar
- Zhao, F., Liu, Y.: [The biosynthesis of polyamines is more sensitive than that of proline to salt stress in barley seedlings.]-Acta phytophysiol. sin. 26: 343–349, 2000. [In Chinese.]Google Scholar
- Zhao, Z., Chen, G., Zhang, C.: Interaction between reactive oxygen species and nitric oxide in drought-induced abscisic acid synthesis in root tips of wheat seedlings.-Aust. J. Plant Physiol. 28: 1055–1061, 2001.Google Scholar