In the present study, both Salicylic (SA) acid and nitric oxide (NO) were proven as signaling molecules in regulating a serial of physiological processes in plants. Using pharmacological and biochemical approaches, we evaluated the protective effect of exogenous salicylic acid against salt-induced oxidative damage in the roots of wheat seedling. Plants exposed to salt (150mmol/L NaCl) exhibited the significant increase of lipid peroxidation as well as the inhibition of root growth. However, SA (100μmol/L) supplementation to NaCl (150mmol/L) treated plants effectively not only reduced the lipid peroxidation and partially increased the root growth, but also activated anti-oxidant enzyme, including superoxide dismutase (SOD), activities.guaiocol peroxidase (POD) and ascorbate peroxidase (APX), which was also mimicked by the application of the nitric oxide (NO) donor sodium nitroprusside (SNP). Further analyses showed that the above ameliorating effects of SA were specific and related to NO, because the specific scavenger of NO 4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt (cPTIO) differentially blocked the above effects. Additionally, SA was able to mimic the effect of SNP by strongly increasing NO release in the roots after daily treatment. Taken together, above results suggest that SA might confer an increased tolerance to salinity stress by enhancing antioxidant defense in wheat seedling roots, which were partially mediated by NO signal.
Key words
wheat seedling;salicylic acid;nitric oxide;antioxidant defense
{{custom_keyword}} /
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1]孙兰菊,岳国峰.植物耐盐机制的研究进展.海洋科学,2001,25(4):28-31.
[2]陈德明.盐渍环境中的植物耐盐性及其影响因素.土壤学进展,1994,22(5):22-29.
[3]Beligni M V, Lamattina L. Nitric oxide stimulates seed germination and de-etiolation,and inhibits hypocotyl elongation,three light-inducible responses in plants. Planta, 2000, 210(2):215-221.
[4]Ruan H H, Shen W B, Ye M B, et al. Protective effects of nitric oxide on salt stress-induced oxidative damages to wheat (Triticum aestivum) leaves. Chin Sci Bull, 2002, 47(23):677-681.
[5]Beauchamp C, Fridovich I. Superoxide dismutase: improved assays and an assay applicable to acrylamide gels. Anal Biochem, 1971, 44(1):276-287.
[6]Hammerschmidt R, Nuckles E M, Kuc J. Association of enhanced peroxidase activity with induced systemic resistance of cucumber to Colletotrchum lagenarium. Physiol Plant Pathol, 1982, 20:73-82.
[7]Nakano Y, Asada K. Hydrogen peroxide is scavenged by ascorbate-specific peroxidase in spinach chloroplasts. Plant Cell Physiol, 1981, 22(5):867-880.
[8]Zhang H, Shen W B, Xu L L. Effects of nitric oxide on the germination of wheat seeds and its reactive oxygen species metabolism under osmotic stress. Acta Bot Sin, 2003, 45(8):901-905.
[9]Bradford M M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem, 1976, 72(1-2):248-254.
[10]Zhou B, Guo Z, Xing J, et al. Nitric oxide is involved in abscisic acid-induced antioxidant activities in Stylosanthes guianensis. J Exp Bot, 2005, 56(422):3223-3228.
[11]Uchida A, Jagendorf A T, Hibino T, et al. Effects of hydrogen peroxide and nitric oxide on both salt and heat stress tolerance in rice. Plant Sci, 2002, 163(3):515-523.
[12]Tanaka Y, Hibino T, Hayashi Y, et al. Salt tolerance of transgenic rice overexpressing yeast mitochondrial Mn-SOD in chloroplasts. Plant Sci, 1999, 148(2):131-138.
[13]Yang Z M, Wang J, et al. Salicylic acid-induced alumimum tolerance by modulation of citrate efflux from toots of Cassia tora L. Planta, 2003, 217(1):168-174.
[14]尹玲莉,侯晓杰.植物抗性信号分子—水杨酸研究进展.中国农学通报,2007,3(1):338-342.
[15]Neill S J, Desikan R, Clarke A, et al. Nitric oxide is a novel componenet of abscisic acid signalling in stomatal guard cells. Plant Physiol, 2002, 128(1):13-16.
{{custom_fnGroup.title_en}}
Footnotes
{{custom_fn.content}}
