RELATIONSHIP BETWEEN SALT STRESS AND NITRIC OXIDE IN GLYCINE MAX L. (SOYBEAN)

摘要

Regarded to be a messenger molecule in recent years, effects of nitric oxide (NO) have been revealed under biotic and abiotic stress conditions. This study explores a possible relationship between salt stress and NO in Glycine max L. (soybean). The 6-days-old G. max seedlings were pre-treated with sodium nitroprusside (SNP), used as NO donor at different concentrations, and carboxy-2-phenyl-4,4,5,5-tetramethyl-imidazoline-l-oxyl-3-oxide(c- PTIO), a synthesized NO scavenger, for 2 days. Afterwards, the seedlings were taken into hydroponic culture containing 100 mM NaCl prepared in 1/2 Hoagland solution. At the end of the experiment, relative water content (RWC), chlorophyll and carotenoid amounts, peroxidase (POD) activity and proline accumulation were determined on different parts (cotyle-done and leaves) of the 19-days-old seedlings. Recovered RWC, chlorophyll and carotenoid destruction, reduced POD activity and increased proline accumulation were observed in the seedlings pre-treated with NO and exposed to salt. One can put forward as a result that certain negative effects were partly avoided by the exogenous application of SNP, and that c-PTIO abated the effects of NO. In addition, NO may play a role in the salt tolerance of G. max seedlings, with the concentration of SNP being quite important.