Journal of Experimental Botany, Vol 49, 1329-1337, Copyright © 1998 by Oxford University Press
M Soussi, A Ocana and C Lluch
Plants of chick-pea (Cicer arietinum L. cv. ILC1919)
inoculated with Mesorhizobium ciceri strain ch-191
were grown in a controlled environmental chamber, and were administered
salt (0, 50, 75, and 100 mM NaCl) during the vegetative period. Four
harvests (4, 7, 11, and 14d after treatment) were analysed. The aim was to
ascertain whether the negative effect of saline stress on nitrogen fixation
is due to a limitation on the photosynthate supply to the nodule or a
limitation on the nodular metabolism which sustains nitrogenase
activity.Plant growth was affected only by the highest NaCl concentration,
whereas nitrogenase activity was affected from 50 mM. At the first harvest,
Rubisco, PEPC and MDH activities in leaves rose with salt, but fell during
the following harvests. The increase of PEPC and MDH in nodules at the two
first samplings was clearly related to salt concentration. While 50 mM NaCl
increased GS and GOGAT in nodules at some harvests, 100 mM strongly
inhibited these activities at all the harvests. The accumulation of
proline, amino acids and carbohydrates was clearly related to salt
especially in the leaves, whereas in the nodules the protein content was
boosted by salt. Although photosynthesis declined with NaCl, the response
of nitrogen fixation to salt was more pronounced. This situation, together
with carbohydrate accumulation, suggests that the lack of photosynthate
does not cause the inhibition of nitrogenase activity under this type of
stress. The similar trend observed for the PEPC-MDH pathway and the ARA
support the hypothesis concerning the limitation in the supply of energy
substrate, mainly malate, to the bacteroids. The accumulation of compatible
solutes is more a consequence of damage produced by salt stress than of a
protective strategy.Keywords: Chick-pea, salt stress,
nitrogen fixation, photosynthesis, ammonium assimilation
ARTICLES
Effects of salt stress on growth, photosynthesis and nitrogen fixation in chick-pea (Cicer arietinum L.)
Departamento de Biología Vegetal, Facultad de Ciencias, Universidad de Granada, E-18071 Granada, Spain; Corresponding author
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  G. S. SCIPPA, M. DI MICHELE, A. DI IORIO, A. COSTA, B. LASSERRE, and D. CHIATANTE The Response of Spartium junceum Roots to Slope: Anchorage and Gene Factors Ann. Bot., May 1, 2006; 97(5): 857 - 866. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. TEZARA, D. MARTINEZ, E. RENGIFO, and A. HERRERA Photosynthetic Responses of the Tropical Spiny Shrub Lycium nodosum (Solanaceae) to Drought, Soil Salinity and Saline Spray Ann. Bot., December 1, 2003; 92(6): 757 - 765. [Abstract] [Full Text] [PDF]
|
|