Nitric oxide reverses glucose-mediated photosynthetic repression in wheat (Triticum aestivum L.) under salt stress

The involvement of nitric oxide (as sodium nitroprusside, SNP) in the reversal of glucose (Glu)-inhibited photosynthetic characteristics in the presence or absence of salt stress (100 mM NaCl) was studied in wheat (Triticum aestivum L.). The plants treated with either NaCl or 6% Glu exhibited reduced photosynthesis due to higher oxidative stress. The increased content of Na+ and Cl-, and lipid peroxidation in plants grown under salt stress were reduced with the application of 50 mu M SNP. The SNP- treated plants with or without 6% Glu exhibited reduced Glu and ethylene sensitivity and oxidative stress, resulting in improved photosynthesis under salt stress through upregulation of antioxidant system, proline accumulation and N assimilation. The results show that SNP improves photosynthetic performance of plants in the absence of salt stress, and also reduces glucose-mediated repression of photosynthesis under salt stress.