Rice genotypes differing in salt tolerance II. Short‐term kinetics of NaCl absorption and translocation in intact plants

Two pairs of contrasting rice genotypes, each pair having similar general characteristics but differing in their tolerance to salt, were compared in short‐term experiments of NaCl absorption and translocation in intact plants. At low external NaCl concentration (0.1 mM), the absorption of Na was passive with a constant net influx rate (I_n), while the absorption of Cl was an active process obeying Michaelis‐Menten kinetics. At both low and high external NaCl concentrations (0.1 and 50 mM), salt‐tolerant ‘Pokkali’ had significantly lower rates of Na and Cl absorption than did salt‐sensitive ‘Peta’, although another moderately salt‐tolerant genotype, ‘IR 29725–25–22–3‐3–3’, did not differ from its salt‐sensitive counterpart, ‘IR 5’. For both pairs of the plants, translocation rates of Na and Cl were significantly lower in the salt‐tolerant genotypes than in the salt‐sensitive ones. It was concluded that exclusion of Na and/or Cl from the shoots may involve both absorption and translocation components of regulation. For relatively salt‐tolerant genotypes, a better regulation of either or both of the two components results in lower Na and/or Cl contents in the shoots, leading to a higher degree of salt tolerance.     

Response of three Sesbania species to salinity when grown hydroponically

The shoot and root growth response of three species of Sesbania to 0, 50 and 100 mM NaCl in a hydroponic culture was studied. Absorption and translocation of Na and Cl in 15 day old seedlings were studied using ²²Na and ³⁶Cl labelled NaCl. Shoot growth was significantly reduced at 100 mM NaCl in the nutrient solution for all three species. The salt tolerance of the three species was in the order S. rostrata > S. aculeata > S. speciosa. The transport of Na to stem and leaf was less compared to uptake in S. rostrata but greater proportion of the absorbed Cl was translocated to the shoot. Salinity reduced the nitrogen content in root and stem significantly.     

Growth,water use efficiency,and sodium and potassium acquisition by tomato cultivars grown under salt stress

Three cultivars of tomato (Lycopersicon esculentum Mill., cvs. Sera, 898, Rohaba) were grown under different levels of NaCl in nutrient solution to determine effects of salt stress on shoot and root dry matter (DM), plant height, water use efficiency (WUE, g DM kg^‐1 water evapotranspired), shoot sodium (Na) and potassium (K) concentrations, and K versus Na selectivity (S_K,Na). Increasing NaCl concentration in nutrient solution adversely affected shoot and root DM, plant height, WUE, K concentration, and K/Na ratio of all cultivars. Shoot Na concentrations increased with increasing NaCl concentration in the nutrient solution. Although increasing salt concentration in the solution adversely affected growth of all cultivars, the cultivar Sera had the highest shoot and root DM than the other two cultivars (898 and Rohaba). Shoot and root DM of cultivar 898 was most affected by salt, while cultivar Rohaba had an intermediate salt sensitivity. The cultivar Sera generally had higher WUE values, shoot K concentrations, and S_K,Na, but had lower shoot Na concentrations than the other two cultivars when plants were grown under different salt levels. Greater Na exclusion, higher K uptake and shoot S_K,Na are suggested as being plant strategies for salt tolerance.     

Effects of Salinity and Nitrogen on Growth,Contents of Pigments,and Ion Accumulation of a Euhalophyte Suaeda Salsa in an Intertidal Zone and on Saline Inland

The different responses of two populations of Suaeda salsa (Linn.) Pall. (saline seepweed) from an intertidal zone and a saline inland zone to salinity [1 or 500 mM sodium chloride (NaCl)] and nitrogen [N; 0.05, 1, or 10 mM nitrate (NO₃ ^?)‐N] were investigated. Greater NO₃ ^?‐N supply (10 mM) increased shoot dry weight for the two populations of S. salsa, especially for S. salsa from the saline inland zone. Greater NO₃ ^?‐N supply (10 mM) increased the concentrations of chlorophyll and carotenoid in leaves and the NO₃ ^? and potassium (K⁺) concentrations in shoots for both populations. Greater NO₃ ^?‐N supply (10 mM) increased shoot Na⁺ in S. salsa from the intertidal zone. In conclusion, S. salsa from the saline inland zone is more responsive to NO₃ ^?‐N supply than the intertidal population. Greater NO₃ ^?‐N supply can help the species, especially the intertidal population, to grow and to mediate ion homeostasis under high salinity.     

Salt tolerance and mineral relations for celery

To invertigate the relationship between salt tolerance and plant mineral status in celery (Apium graveolens L.) growth and the concentration of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sodium (Na), and chloride (Cl) in different tissues were determined in plants grown in hydroculture with nutrient solutions containing 5 (control), 50,100, and 300 mM sodium chloride (NaCl) for four weeks. At salinity levels of 50 and 100 mM NaCl, there was a moderate, albeit significantly, reduction of growth, while a drastic decrease in both fresh and dry weight was obtained at 300 mM NaCl. Regardless of the salinity level, growth resumed promptly and completely once the stress was ceased. Sodium chloride stress reduced the accumulation of nitrate (NO₃)‐N in all plant tissues, but there were no relevant effects on the concentration of reduced N and P. The concentration of K in roots and leaf petioles was unaffected by NaCl treatment, but it gradually declined with increasing salinity in leaf blades. This reduction was less pronounced in the young leaves as compared to the mature ones. Increasing the NaCl concentration decreased the concentration of Ca in all tissues, but it prevented the occurrence of black‐heart, a typical Ca‐related physiological disorder which affected severely the controls. Salt‐stressed plants absorbed large amounts of Na and Cl which accumulated in the mature leaves, particularly in the oldest leaves. These findings suggest that the relatively high salt tolerance of celery relies on the ability to maintain an adequate nutritional status and to protect the shoot meristem from salt toxicity.     

Significance of salt transport patterns in rice varieties differing in salt tolerance

Abstract

The absorption mechanisms for Na, K, SO₄ and Cl were tested in a salt tolerant (PVR 1) and a salt sensitive (GEB 24) rice varieties. The salt tolerant variety accumulated significantly larger amounts of Na than the salt sensitive variety. Further, PVR 1 absorbed SO₄ from Na₂SO₄ in preference to that from K₂SO₄. The absorption patterns for K and Cl were similar in both the varieties. It is concluded that the capacity of plant species to accumulate greater amounts of Na is a reflection of their halophytic feature.     

Effects of NaHCO3 on photosynthetic characteristics,and iron and sodium transfer in pomegranate

In order to study effects of sodium bicarbonate (NaHCO₃) stress in irrigation water on photosynthetic characteristics and iron (Fe) and sodium (Na⁺) translocation content of pomegranate plants, a factorial experiment was conducted based on completely randomized design with three cultivars of pomegranate (“Gorch-e-Dadashi,” “Zagh-e-Yazdi,” and “Ghermez-e-Aliaghai”) and four concentrations of NaHCO₃ (0, 5, 10, and 15 mM), with three replications. The results of plant analysis indicated that NaHCO₃ affected chlorophyll index, F_v/F_m, and performance index (PI) in upper and lower leaves of shoots and also the translocation of Na⁺ and Fe. The results also showed that Fe translocation from root to shoot reduced at 15 mM level of NaHCO₃. The highest Na translocation and the lowest Fe translocation were observed in Zagh-e-Yazdi and Ghermez-e-Aliaghai cultivars, respectively. The ratio of sodium/potassium (Na⁺/K⁺) in stems was higher than that in roots and leaves, and the observed chlorophyll content of upper leaves was also lower than that of lower leaves. Based on the measured parameters Gorch-e-Dadashi cultivar showed less relative sensitivity than other cultivars to NaHCO₃ of irrigation water through maintaining the lower Na⁺ transport to the shoots, and improvement of Fe transport to shoots.     

Is the salt tolerance of maize related to sodium exclusion? I. Preliminary screening of seven cultivars

Maize (Zea mays L.) plants in the early stage of development were treated with 80 mM sodium chloride (NaCl) with or without supplemental calcium (Ca²⁺) (8.75 mM) for a seven day period. The effects of salinity on dry matter production and shoot and root concentrations of sodium (Na⁺), Ca²⁺, and potassium (K⁺) were measured for seven Pioneer maize cultivars. Salinity significantly reduced total dry weight, leaf area, and shoot and root dry weight below control levels. For all seven cultivars, Na⁺concentrations were reduced and leaf area was significantly increased by supplementing salinized nutrient solutions with 8.75 mM calcium chloride (CaCl₂). The two cultivars with the lowest shoot and root Na⁺ concentrations under NaCl‐salinity showed the greatest increases in total, shoot and root dry weights with the addition of supplemental Ca. Shoot fresh weight/dry weight ratios for all cultivars were decreased significantly by both salinity treatments, but supplemental Ca²⁺ increased the ratio relative to salinity treatments without supplemental Ca. Root fresh weight/dry weight ratios were decreased only by salinity treatments with supplemental Ca. With NaCl‐salinity, cultivars which had lower shoot and root Na⁺ concentrations were found to be more salt sensitive and had significantly lower amounts of dry matter production than those cultivars which had higher shoot and root Na⁺ concentrations. It was concluded that Na⁺ exclusion from the shoot was not correlated with and was an unreliable indicator of salt tolerance for maize.     

Ammonium increases the net rate of sodium influx and partitioning to the leaf of muskmelon

The influx and partitioning of sodium (Na) is controlled by potassium (K)/Na selectivity/exchange mechanisms. Since ammonium‐nitrogen (NH₄‐N) has been shown to inhibit K absorption and K/Na selectivity/exchange mechanisms control Na influx and partitioning, our objective was to observe if NH₄‐N affects Na influx and partitioning in muskmelon. Muskmelon (Cucumis melo L.) were grown in a pH controlled nutrient solution with 100 mM NaCl in a complete nutrient solution containing either 10 mM nitrate‐nitrogen (NO₃‐N) or NH₄‐N. With NH₄‐N, Na accumulation and partitioning to the leaf blade increased while K absorption was almost completely inhibited. A second study omitted K to simulate the inhibition of K absorption by NH₄‐N and monitored Na accumulation and partitioning as K was depleted in the plant. Sodium accumulation and partitioning to the leaf increased as K decreased in the plant, mirroring the effect of NH₄‐N. Roots appeared healthy in both studies. Our work indicates that at a given level of NaCl stress, NO₃‐N reduces the level of stress experienced by muskmelon plants through reducing the net rate of Na influx and transport to the sensitive leaf blade, not by reducing chloride (Cl) absorption, thereby permitting these plants to “avoid”; this stress.     

Effects of Potassium Sulfate on Adaptability of Sugarcane Cultivars to Salt Stress under Hydroponic Conditions

The effect of potassium sulfate (K₂SO₄) on adaptability of sugarcane to sodium chloride (NaCl) stress was investigated under hydroponic conditions. Two sugarcane cultivars, differing in salinity tolerance, were grown in half strength Johnson's solution at 80 mM NaCl with 0, 2.5 and 5.0 mM potassium (K) as K₂SO₄. Salinity disturbed above and below-ground dry matter production in both sugarcane cultivars. However, salt sensitive cultivar showed more reduction in shoot dry matter and higher root:shoot ratio compare to the salt tolerant cultivar under. Application of K significantly (p < 0.05) improved dry matter production in both sugarcane cultivars. The concentration of Na was markedly increased with increasing salinity; however, the application of K reduced its uptake, accumulation and distribution in plant tissues. Salinity induced reduction in K concentration, K-uptake, K utilization efficiency (KUE) and K:Na ratio in both sugarcane cultivars was significantly improved with the addition of K to the saline growth medium.     

Growth Responses and Nitrogen-15 Absorption of Desert Saltgrass Under Salt Stress

Abstract

Saltgrass [Distichlis spicata (L.) Greene var. stricta (Gray) Beetle], accession WA-12, collected from a salt playa in Wilcox, AZ, was studied in a greenhouse to evaluate its growth responses in terms of shoot and root lengths, shoot dry-matter yield, and nitrogen (N) (regular and ¹⁵N) absorption rates under control and salt (sodium chloride, NaCl) stress conditions. Plants were grown under a control (no salt) and three levels of salt stress (100, 200, and 400 mM NaCl, equivalent to 5850, 11700, and 23400 mg L^{? 1} sodium chloride, respectively), using Hoagland solution in a hydroponics system. Ammonium sulfate [(¹⁵NH₄)₂SO₄], 53% ¹⁵N (atom percent ¹⁵N) was used to enrich the plants. Plant shoots were harvested weekly, oven-dried at 60°C, and the dry weights measured. At each harvest, both shoot and root lengths were also measured. During the last harvest, plant roots were also harvested and oven-dried, and dry weights were determined and recorded. All harvested plant materials were analyzed for total N and ¹⁵N. The results showed that shoot and root lengths decreased under increasing salinity levels. However, both shoot fresh and dry weights significantly increased at 200 mM NaCl salinity relative to the control or to the 400 mM NaCl level. Shoot succulence (fresh weight/dry weight) also increased from the control (no salt) to 200 mM NaCl, then declined. The root dry weights at both 200 mM and 400 mM NaCl salinity levels were significantly higher than under the control. Concentrations of both total-N and ¹⁵N in the shoots were higher in NaCl-treated plants relative to those under the control. Shoot total-N and ¹⁵N contents were highest in 200 mM NaCl-treated plants relative to those under the control and 400 mM salinity.     

Use of IR thermography in screening wheat (Triticum aestivum L.) cultivars for salt tolerance

Thermography is proposed to be an alternative non-destructive and rapid technique for the study and diagnosing of salt tolerance in plants. In a pot experiment, 30 cultivars of wheat (Triticum aestivum L.) were evaluated in terms of their leaf temperature and shoot growth and their ion distribution responses to NaCl salinity at two concentration levels: the control with electrical conductivity (EC) of 1 dS m^?1 and salinity treatment with EC of 16 dS m^?1 (150 mM). A completely randomized block design with factorial treatments was employed with three replications. The results indicated that thermography may accurately reflect the physiological status of salt-stressed wheat plants. The salt stress-based increase in leaf temperature of wheat cultivars grown at 150 mM NaCl reached 1.34°C compared to the control. According to the results obtained, it appears that thermography has the capability of discerning differences of salinity tolerance between the cultivars. Three salt-tolerant wheat cultivars, namely Roshan, Kharchia and Sholeh, had higher mean shoot dry matter (0.039 g plant^?1) and higher mean ratio of leaf K⁺/Na⁺ (14.06) and showed lower increase in the mean leaf temperature (0.37°C) by thermography compared to the control. This was while nine salt-sensitive cultivars, namely Kavir, Ghods, Atrak, Parsi, Bahar, Pishtaz, Falat, Gaspard and Tajan, had lower mean plant dry matter production (0.027 g plant^?1), lower mean ratio of K⁺/Na⁺ (9.49) and higher mean increases in leaf temperature (1.24°C).     

Influence of extreme K:Na ratios and high substrate salinity on plant metabolism of crops differing in salt tolerance

Mineral regulation of two soybean varieties Jackson and Lee was investigated in long term water culture experiments using saline solutions. The effects of extreme K:Na ratios using chloride and sulfate as counterions were studied in the early stages of salinity.

The growth rates of both varieties were not affected by salinization. A K⁺ stimulated, intensive acropetal Cl^‐ translocation was observed in the salt sensitive variety Jackson. The varieties did not differ in Na⁺ translocation and in the suppression of Ca²⁺ and Mg²⁺ in the leaves. But the effect of the nature of salinization indicates already differences in Na uptake and translocation of the cultivars.

The avoidance of Cl^‐, but also of Ha⁺, in connection with influences of the resulting ionic imbalance on metabolic pathways are probably the most causative factors for the different tolerance to salinity of the two soybean varieties.     

Salt stress effects on enzymes activities involved in carbon metabolism and nitrogen availability of two Tunisian durum wheat varieties

Two varieties of durum wheat (Om Rabiaa and Karim), were analyzed and evaluated in the presence of increasing doses of NaCl (0, 100, 200 and 300?mM) in which we added different concentrations of nitrate (0.1, 3, 10?mM). The data obtained showed that presence of NaCl in the culture medium induces the increase of the salt accumulation levels (Na⁺, Cl^?) and reduces the levels of K⁺ and NO₃^? in the cultivar Om Rabiaa. In Karim variety, ions that have been heavily accumulated following exposure to NaCl are Na⁺ and K⁺ while low levels of NO₃^? and Cl^? have been detected. Those findings highlight the difference in the salinity tolerance of durum wheat cultivars also depending on nitrogen (N) availability, Karim cultivar being less sensitive to NaCl treatment than Om Rabiaa. These data also suggested a relationship between salt tolerance capacity and enhancement of nitrogen and carbon metabolisms enzyme activity.     

Effect of nitrogen nutrition on salt tolerance of Pisum sativum during vegetative growth

The influence of different nitrogen (N) forms on salt tolerance of Pisum sativum L. was investigated. Plants of the pea cultivar “Resal” were subjected to 0 (control) or 90 mM NaCl and one of the following nitrogen forms: 5 mM mineral N supplied as either NO , NH , or NH₄NO₃ or N supplied by biological N₂ fixation (inoculated with Rhizobium leguminosarum bv. viciae). Root and shoot biomass were determined 15, 30, 45, and 60 d after emergence, and Na⁺, K⁺, and Cl^– concentrations were determined by capillary electrophoresis. Nitrogen sources induced significant differences in plant growth and in ion accumulation and distribution and in differentially affected salt tolerance. In the absence of salt, the largest biomass accumulation was obtained with NH₄NO₃. In the presence of NaCl, NO ‐fed plants experienced less salt toxicity than plants supplied with other N sources, as indicated by lower Na⁺ and Cl^– and higher K⁺ concentrations in the shoot. The results also suggest that it is possible to establish an effective symbiosis under saline conditions, provided that a salt‐tolerant Rhizobium isolate with good N₂‐fixing ability is used. The use of the appropriate N‐fertilizer source can enhance the growth of Pisum sativum. Hence, NH₄NO₃ may be preferably used under non‐saline and NO under moderately saline conditions.     

Barley response to salt stress at varied levels of phosphorus

Increasing plant phosphorus (P) supply can increase or decrease salt tolerance of many plants. Barley (Hordeum vulgare L., cv. ACSAD 176) was grown in nutrient solution under controlled conditions to determine effects of P level on detrimental effects of sodium chloride (NaCl). Increasing level of P improved tolerance of barley to NaCl. At 3, 30, and 60 μM P, the NaCl concentrations to reduce shoot dry matter (DM) by 50% were 158, 193, and 260 mM, respectively. Increased NaCl levels reduced shoot P concentrations. Plants grown with NaCl had higher Internal P requirements. When NaCl in solution was 10, 150, and 300 mM, the corresponding concentrations of P in shoots required to obtain 50% DM were 1.6, 4.2, and 4.7 mg‐g^‐1 dry weight, respectively. Increasing solution P level from 3 to 60 μM P decreased sodium (Na) and increased potassium (K) concentrations in shoots. Accumulation of mineral ions for osmotic adjustment and restriction of Na accumulation in shoots was involved in P enhancement of salt tolerance of barley.     

Differentiation of chloride and sulphate salinity on the basis of ionic distribution in genetically diverse cultivars of wheat

Sulphate (SO₄) salinity, in general, was found to be more injurious than chloride (Cl) salinity in all the four genetically diverse wheat cultivars—Triticum monococcum (Cl), T. aestivum cv. Chinese spring (C2), T. turgidum cv. langdon (C3) and amphidiploid (C4) obtained by a cross between T. aestivum cv. Chinese spring x Thinopyrum bessarabicum grown in hydroponic cultures containing iso‐osmotic saline treatments T1 (90 mM NaCl), T2 (45 mM NaCl+22.5 mM Na₂SO₄), T3 (15 mM NaCl + 37.5 mM Na₂SO₄), and T4 (45 mM Na₂SO₄). Among the cultivars, C4 followed by C2 and C3 appeared to be more salt resistant and Cl the most salt sensitive as far as various observations on osmotic potential and internal ion accumulation were concerned. Salt resistance could be ascribed to more exclusion of Na and Cl ions. Sulphate injury might be due to less effective sequestration or mobility of this ion towards some innocuous centres of plant tissues. Most of the interactive effects of cultivar versus salinity were prominently higher in cultivar C4 in treatment T1.     

Genotype-Dependent Differential Responses of Three Forage Species to Calcium Supplement in Saline Conditions

Salt toxicity comprises of osmotic and ionic components both of which can severely affect root and shoot growth. In many crop species, supplemental calcium (Ca) reduces the inhibition of growth typical of exposure to salt stress. The objective of this study was to compare whole plant growth and physiological responses to interactive effect of salinity and Ca level on three forage species [African millet (AM), tall wheat grass (TW), and perennial ryegrass (PR)] differing in tolerance to sodium chloride (NaCl) salinity. Plants were grown under glasshouse condition and supplied with nutrient solution containing 0, 100, and 250 mM NaCl supplemented with 0.5, 5, or 10 mM calcium chloride (CaCl₂). Plant growth, ionic concentration, water relations, and solute (proline and glycinebetaine) concentrations of the plants were determined two weeks after the salinity treatments. At 100 mM NaCl, there was a moderate reduction in dry matter (DM) production of all three species. A drastic decrease in DM occurred at 250 mM NaCl. Supplemental Ca reduced the adverse effects of salinity on all three species. The TW showed higher shoot and root growth in 100 and 250 mM NaCl than AM and PR. It also showed the highest DM at 5 and 10 mM Ca supplement. The shoot and root DM of TW increased by about 45 and 15%, respectively compared to the control. Chemical analysis indicated that in TW, Ca restricted both uptake and transport of sodium (Na) from root to shoot. It also increased Ca and potassium (K) concentrations in both organs. The transport of K and Ca from root to shoot of AM and PR were decreased by NaCl, but were restored with increasing Ca in the medium. The opposite occurred for Na. In PR, more K uptake was observed in shoot at 250 mM NaCl with 10 mM Ca supplement. The sap osmotic potential (Ψ_S) was the highest in TW at 10 mM Ca in the presence of 250 mM NaCl. Contribution of various solutes to the difference in Ψ_S among the species from the control and 250 mM salt treatment differed greatly. Supplemental Ca induced decline in the leaf Ψ_S of TW which was predominately due to K, glycinebetaine, Na and proline accumulation. Addition of 10 mM Ca to the growth medium maintained a low Na and a high K level. Accumulation of glycinebetaine and proline in leaf contributed the NaCl tolerance of TW. The presented results suggest that supplement Ca, not only improved ionic relations but also induced plant ability in production of compatible solutes (glycinebetaine and proline) and osmotic adjustment. Accordingly, genotype dependent capacity could be found using supplemental Ca.     

H+‐atpase and H+‐transport activities in tonoplast vesicles from barley roots under salt stress and influence of calcium and abscisic acid 1

Seedlings of two barley cultivars differing in NaCl sensitivity were treated with low (100 mM) or high (400 mM) concentration of NaCl for 6 days. Tonoplast vesicles were prepared from roots, and H⁺‐ATPase and H⁺‐transport activities associated with tonoplast were assayed. Both H⁺‐ATPase and H⁺‐transport activities in the two cultivars were increased at 100 mM NaCl. These activities also increased in the salt‐tolerant cultivar at 400 mM NaCl, but in salt‐sensitive cultivar were decreased. In vivo treatment with 10 mM Ca²⁺ stimulated H⁺‐ATPase and H⁺‐transport activities at two levels of NaCl, however, treatment with 10⁵M (±) abscisic acid (ABA) inhibited these activities. From these results we propose that the increase of the vacuolar H⁺ pumps in barley roots reflects an adaptation to salt stress. The stimulation of HVATPase and H⁺‐transport activities by calcium (Ca) depends mainly on its effect in maintaining stability of membrane under salt stress.     

Growth response of Suaeda salsa (L.) Pall to graded NaCl concentrations and the role of chlorine in growth stimulation

Abstract

Growth response of a halophyte species, Suaeda salsa (L.) Pall, to graded NaCl concentrations was examined under water culture conditions. Growth increased with increasing NaCl concentration from 2 to 200 mol m^?3, but decreased at NaCl concentrations above 200 mol m^?3. Maximum growth was attained at 50 to 200 mol m^?3. The role of Na and Cl in the growth stimulation by NaCl was examined by growing S. salsa in nutrient solutions with or without Na and Cl separately at 5 and 50 mol m^?3. The growth stimulation induced by Cl was greater than that induced by Na, and Na did not significantly induce growth stimulation. The effect of Na or Cl on O₂ evolution from leaves was examined under 5 and 50 mol m^?3 concentrations using an oxygen electrode. Oxygen evolution from leaves in –Cl treatments was smaller than that in +Cl treatments both at 5 and 50 mol m^?3. The O₂ evolution in Na treatments with Cl was similar to that at NaCl. These results indicated that the mechanism of growth stimulation induced by Cl was mainly an increased photosystem II of photosynthesis in leaves. The contribution of Na on the growth stimulation of S. salsa by NaCl was smaller than Cl.