Salinity affects indirectly nitrate acquisition associated with glutamine accumulation in cowpea roots

• Published in: Biologia plantarum Vol. 56; no. 3; pp. 575 - 580
• Main Authors: Silveira, J. A. G, Melo, A. R. B, Martins, M. O, Ferreira-Silva, S. L, Aragão, R. M, Silva, E. N, Viégas, R. A
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer-Verlag 01.09.2012; Springer Netherlands; Institute of Experimental Botany of the Czech Academy of Sciences
• Subjects: Biomedical and Life Sciences; Brief Communication; calcium; cowpeas; glutamate-ammonia ligase; glutamine; glutamine synthetase; Life Sciences; nacl stress; nitrate reductase; nitrate uptake; nitrates; Plant Sciences; protein content; roots; salinity; sodium chloride; vigna unguiculata; nitrate reductase; glutamine synthetase; nitrate uptake; NaCl stress
• ISSN: 0006-3134; 1573-8264
• DOI: 10.1007/s10535-012-0065-7

The aim of this study was to test the hypothesis that salinity can affect indirectly the nitrate acquisition by a negative modulation triggered by glutamine accumulation. Cowpea plants were exposed to a mild NaCl concentration (50 mM) in order to restrict growth and N-demand. After 21 d, pretreated plants and control plants were supplied with 0, 5 and 10 mM of Ca(NO3)2 for 3 d in absence of NaCl. Salt pretreated plants showed a great limitation in acquisition of NO3 −, indicated by decline in the nitrate uptake rate, NO3 − accumulation, nitrate reductase activity and protein content. The restriction of NO3 − utilization was positively associated with increased glutamine synthetase activity and glutamine accumulation, especially in roots.