Effects of salt stress on growth, photosynthesis and nitrogen fixation in chick-pea (Cicer arietinum L.)

Abstract

utes is more a consequence of damage produced by salt stress than of a protective strategy. Plants of chick-pea (Cicer arietinum L. cv. ILC1919) inoculated with Mesorhizobium ciceri strain ch-191 Key words: Chick-pea, salt stress, nitrogen fixation, photowere grown in a controlled environmental chamber, synthesis, ammonium assimilation. and were administered salt (0, 50, 75, and 100 mM NaCl) during the vegetative period. Four harvests (4, 7, 11, and 14 d after treatment) were analysed. The

Nitrogen fixation is synchronized with carbon metabolism inLotus japonicusandMedicago truncatulanodules under salt stress

“…A strong correlation between sugar accumulation and osmotic stress tolerance has been widely reported (Gilmour et al 2000;Streeter et al 2001;Taji et al 2002), which support a higher tolerance of L. japonicus nodules to salt stress. M. truncatula nodules did not show nodule carbohydrate accumulation; however, amino acids accumulated in these nodules by NaCl, which could be explained as a consequence of damage produced by saline stress, in accordance with results of Gordon et al (1997), Soussi et al (1998) and Khadri et al (2007) in nodules of soybean, chickpea and common bean, respectively.…”

“…Shoot growth was more extensively affected than root growth in L. japonicus plants, consequently increases of root to shoot ratio with NaCl in L. japonicus plants are observed. Similar results have been detected in other legumes such as Cicer arietinum (Soussi et al 1998) and Phaseolus vulgaris (Khadri et al 2006), where the authors considered this behaviour profitable since it could improve plant water status by increasing the root requirements to explore a higher soil volume. The specific nitrogenase activity (mmol H 2 g (1 ) decreased from the vegetative (0 DAT) to the fructification stage (28 DAT) in nodules of both legumes; however, the nodular mass (data not shown) augmented in this period, by which the total nitrogenase activity (mmol H 2 plant (1 ) did not decrease in the same extend, supplying fixed nitrogen for the plant growth.…”

“…4.1.1.31) and malate dehydrogenase (E.C. 1.1.1.37) activity assays were optimiced from the Soussi et al (1998) method. Activity was followed by oxidation of NADH at 340 nm.…”

“…Symbiotic nitrogen fixation in legume nodules is extremely sensitive to environmental stresses such as salinity, which seriously limit legume yields. Salt stress affects several physiological processes in root nodules, such as the range of carbon substrate available to the bacteroids (Delgado et al 1993;Soussi et al 1998) and the activity of enzymes related to carbon metabolism (Khadri et al 2001;Serraj 2002). Nitrogen-fixing plants are more sensitive to salinity than N-fertilized plants (Gonza´lez et al 2001).…”

Rhizosphere and endophytic bacteria for induction of salt tolerance in gladiolus grown in sodic soils

“…In the present study, other than floral characters, higher corm weight and corm diameter were observed in the bio-primed corms, whereas a decreased corm weight and corm diameter were found in untreated control. An overall reduction in control under salt stress was earlier observed by Soussi et al (1998). This reduction in weight of plants under stress may be due to the inhibition or hydrolysis of reserved food and its translocation to growing shoot portion (Singh et al 2008).…”