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1.
The effects of salinity due to sodium chloride (NaCl) and nitrogen (N) concentration in the nutrient solution were studied with sweet pepper plants. Four saline treatments combined with two N fertilization were used. Nitrate‐nitrogen (NO3 ‐N) presence in the nutrient solution produced an increase of sodium (Na) and potassium (K) contents in leaves as well as N. Salinity promoted a reduction of K, phosphorus (P) and Ca and increased the Na concentration in leaves. Calcium (Ca) concentrations were lower in the higher NO3 ‐N treatment although N level was reached adding calcium nitrate and salinity increased P, K, Na, Ca, and magnesium (Mg) contents in fruits. Yield was increased in the highest N treatment.  相似文献   

2.
Alfalfa (Medicago sativa L.) yield and nutrient contents may be affected under salinity condition. Thus, this experiment was conducted to determine the effect of three salinity levels (60, 120, and 180 mM NaCl) on shoot and root dry weights, and mineral contents of three alfalfa cultivars. With the increasing salinity levels sodium (Na) and magnesium (Mg) contents increased; but potassium (K), nitrogen (N), phosphorous (P), calcium (Ca), zinc (Zn), and copper (Cu) contents and root and leaf weights decreased; however, changes in these traits depended on cultivar and salinity level. However, Rehnani, a tolerant cultivar, had the lowest Na and Mg contents and the highest K, N, P, Ca, Zn, and Cu contents and dry weights under all of the salinity levels. Moreover, leaf dry weight and leaf P content had the highest correlation with salt tolerance suggesting that these traits may be used as a marker for selecting salts that are tolerant among genotypes in alfalfa.  相似文献   

3.
Abstract

The compartmentation of ions in salinity‐stressed 6‐week‐old alfalfa seedlings was investigated in two cultivars, Batini (moderately salinity tolerant) and Hunter River (salinity sensitive). Both cultivars were grown under field conditions during the cool season (20–25°C) and the warm season (35–46°C). Two saline solutions (6.4 and 12.2 dS m‐1) were prepared by dissolving the required quantity of NaCl in half‐strength Hoagland solution. Tap water (0.8 dS m‐1) served as control. Plants were irrigated twice a week with saline solutions, commencing 3 weeks after seedling emergence. The seedlings were separated into leaf (including petiole), stem, and root after 6 weeks of growth and analysed for phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), chloride (Cl), and micronutrients [copper (Cu), boron (B), zinc (Zn), manganese (Mn), and iron (Fe)]. The concentration of P and K in the plant tissue increased with increase in temperature, while Ca and Mg concentrations were depressed. Increase in salinity, in general, resulted in decreased accumulation of all ions, including micronutrients. Hunter River maintained the same pattern of ion compartmentation (root<stem<leaf) for Na and Cl, whereas in Batini a different pattern was obtained for Na (stem<leaf<root). Since the compartmentation pattern of ions in Batini is different for Na and not Cl, it appears that compartmentation of Na may be an important factor in salt tolerance.  相似文献   

4.
The effects of different levels of arsenic (As) and salinity on bean plant (Phaseolus vulgaris L., cv. Buenos Aires) nutrition were investigated. We studied the processes of absorption and accumulation of chloride (Cl) and micronutrient elements: boron (B), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn). The experiment was performed in soilless culture at two levels of As: 2 and 5 mg As L‐1 [added as sodium arsenite (NaAsO2)], and three saline levels [only sodium chloride (NaCl) was added]: 1, 2, and 4 dSm‐1. Sodium arsenite and NaCl significantly affected micronutrients allocation within the bean plant at levels used in this study. Arsenite depressed Mn and Cl concentrations in the root, whereas root B, Cu, and Zn levels were increased. Boron, Cu, Fe, and Cl concentrations were significantly higher in As‐stressed plants compared with controls. The addition of NaCl increased the Cl and Mn concentrations in roots and Cl, Fe, and Mn in leaves.  相似文献   

5.
Poor quality of irrigation water (high salinity) has reduced the yields of pistachio over recent years, especially in Kerman. The effects of four salinity levels [0, 30, 60, and 90 mM sodium chloride (NaCl)] and three calcium (Ca) levels [0, 0.5, and 1 mM Ca as calcium nitrate (Ca(NO3)2.4H2O)] on growth and chemical composition of pistachio seedlings cv. ‘Badami’ were studied in sand culture under greenhouse conditions in completely randomized design (CRD) with four replications. After 170 days, leaf area, leaf number, shoot and root dry weights were determined. Also shoot and root sodium (Na), potassium (K), Ca, and magnesium (Mg) concentrations were measured. Results showed salinity decreased all growth parameters. Ca application increased shoot and root Ca concentrations and root K concentration, while Ca application decreased shoot K concentration and shoot and root Mg concentrations. Salinity decreased shoot Ca, root K, and root Mg concentrations, while salinity increased shoot and root total sodium uptake, and shoot and root Cl concentrations.  相似文献   

6.
The response of bean plants (Phaseolus vulgaris L.) to different levels of arsenic (As) and salinity was investigated, including the processes of uptake, distribution, and accumulation of As and the effect of arsenite and salinity on plant growth and fruit production. The experiment was performed in soilless culture at two levels of As: 2 and 5 mg As L‐1 [added as sodium arsenite (NaAsO2)], and three saline levels [only sodium chloride (NaCl) was added]: 1,000,2,000, and 4,000 μS#lbcM‐1. Arsenic uptake and concentration in root increased upon increased NaAsO2 concentration in the nutrient solution. However, the increase in the As root content was not proportional to the As level in the nutrient solution. High levels of salinity in solution decreased As uptake and the concentration of As in root, stem, and leaf. Upon uptake, As was readily translocated to the aerial organs and approximately half of the absorbed As was transported to the upper parts of the bean plants. The As concentration in fruit always remained below the recommended limit for As content in fruit and edible vegetal products. While salinity did not significantly affect plant growth, arsenite was found to be phytotoxic to the bean plants.  相似文献   

7.
The effect of salinity on growth response, nitrogen (N) fixation and tissue mineral content was investigated for four legumes: faba bean (Vicia faba L), pea (Pisum sativum L), soybean (Glycine max L), and common bean (Phaseolus vulgaris L). Plants were grown in a vermiculite culture system supplied with a N‐free nutrient solution with the addition of 0, 50, and 100 mM NaCl. Plants were harvested at the beginning of the flowering period and the dry weights of shoots and roots and acetylene reduction activity (ARA) were evaluated at the same time plant tissues were analysed for N, potassium (K), calcium (Ca), magnesium (Mg), and sodium (Na) contents.

The depressive effect of saline stress on ARA of nodules was directely related to the salt induced decline in dry weight and N content in shoots. Growth inhibition by NaCl treatments was greater for the pea than for other legumes, whereas the soybean was the most salt‐tolerant Saline stress also affected the N content in shoots and roots. In general the N content accumulated in the shoot and Na in the roots of the four legumes tested, while K accumulated both organs. The acquisition of other macronutrients differed according to the legume species. The legumes most sensitive were P. sativum and V. faba which accumulated Ca in shoot and Mg both in the shoot and the roots. On the contrary, in G. max and P. vulgaris, the two most salt tolerant legumes, accumulated Mg in the roots and Ca in both vegetative organs. Our results suggest a relationship between the salt‐tolerant range in legumes and the macronutrient accumulation in vegetative organs.  相似文献   

8.
Crop production in many parts of the world is increasingly affected by soil salinization, especially in the irrigated fields of arid and semi-arid regions. The effects of four magnesium levels [0, 0.5, 1, and 22 millliMolar (mM) magnesium as magnesium sulfate (MgSO4.5H2O)], and three salinity levels [0, 45 and 90 mM sodium chloride (NaCl)] on growth and the chemical composition of pistachio seedlings (Pistacia vera L.) cv. ‘Badami-e-Zarand’ was studied in sand culture under greenhouse conditions. The experiment was set up as a completely randomized design (CRD) with four replications. After 28 weeks the growth parameters of biomass, leaf number, leaf area and stem height were measured. The results demonstrated that salinity decreased biomass, leaf area and stem height; the application of 2 mM magnesium (Mg) significantly reduced biomass, leaf number, leaf area and stem height; salinity stress increased concentrations of sodium (Na) and potassium (K) in shoot as well as Na concentration in root; however, it decreased Mg and calcium (Ca) concentrations in shoot, as well as Mg, Ca, and K concentrations in root. The application of 2 mM Mg reduced K and Ca concentrations in shoot and Na and K concentrations in root.  相似文献   

9.
Abstract

Salinity affects plants by interaction between sodium (Na) and calcium (Ca). Two sorghum (Sorghum bicolor) genotypes ('Hegari’ and ‘NB‐9040') were studied for the Na x Ca interaction in a soil amended with 2% calcium carbonate (CaCO3) and with 0, 12.3, 24.6, and 36.9 mmol sodium chloride (NaCl)/kg soil. The two genotypes were similar in their response to soil NaCl in their shoot and root growth but differed in response to lime. The salinity‐tolerant Hegari was suppressed by high Ca concentration in the soil, mainly in the low‐NaCl treatments, and responded by a lower concentration of potassium (K) and magnesium (Mg) in the leaves, which was associated with leaf‐chlorosis. Since Na uptake was reduced by Ca, the main effect of salinity on plant growth was by the accumulation of chloride (Cl) in the leaves.  相似文献   

10.
Results of several studies show interactive effects of salinity and macronutrients on the growth of wheat plants. These effects may be associated with the nutrient status in plant tissues. The objective of this study was to investigate interactive effects of salinity and macronutrients on mineral element concentrations in leaves, stems, and grain of spring wheat (Triticum aestivum L. cv. Lona), grown in hydroponics, and the relation of these effects to yield components. Eight salinity levels were established from 0 to 150 mM NaCl, and 1, 0.2, and 0.04 strength Hoagland macronutrient solution (x HS) were used as the macronutrient levels. Sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), chlorine (Cl), and phosphorus (P) in leaves, stems, and grain, NO3 in leaves and stems, and total nitrogen (N) in grain were determined. Supplemental Ca, Mg, K, and NO3 added to 0.2 x HS increased mineral concentrations in leaves and stems, but did not improve growth or yield in salinized wheat plants except moderately at 100–150 mM NaCl. In contrast, growth or yield was improved significantly when the concentration of macronutrients was increased from 0.04 to 0.2 × HS. In contrast to leaves and stems, mineral concentrations in grain increased (Na, Cl) or decreased (Ca, Mg, K) only slightly or were not affected (K) by salinity except at high salinity and low macronutrient level. Nitrogen and P concentrations in grain were not affected by salinity. Sodium and Cl concentrations in leaves and stems increased significantly, whereas K and NO3 decreased significantly, with an increase in salinity regardless of the macronutrient level. The latter was also observed for Ca and Mg in leaves. Extreme Na/Ca ratios in plant tissues negatively affected grain yield production at high salinity with medium or high macronutrient levels and at low macronutrient level together with medium salinity. Even though strong and significant correlations between mineral concentration at grain maturity in leaves, stems, and grain and various yield parameters were observed, our results are inconclusive as to whether toxicity, nutrient imbalance, nutrient deficiency, or all of these factors had a strong influence on grain yield.  相似文献   

11.
Plants grown in salt‐affected soils may suffer from limited available water, ion toxicity, and essential plant nutrient deficiency, leading to reduced growth. The present experiment was initiated to evaluate how salinity and soil zinc (Zn) fertilization would affects growth and chemical and biochemical composition of broad bean grown in a calcareous soil low in available Zn. The broad bean was subjected to five sodium chloride (NaCl) levels (0, 10, 20, 30, and 40 m mol kg?1 soil) and three Zn rates [0, 5, and 10 mg kg?1 as Zn sulfate (ZnSO4) or Zn ethylenediaminetetraaceticacid (EDTA)] under greenhouse conditions. The experiment was arranged in a factorial manner in a completely randomized design with three replications. Sodium chloride significantly decreased shoot dry weight, leaf area, and chlorophyll concentration, whereas Zn treatment strongly increased these plant growth parameters. The suppressing effect of soil salinity on the shoot dry weight and leaf area were alleviated by soil Zn fertilization, but the stimulating effect became less pronounced at higher NaCl levels. Moreover, rice seedlings treated with ZnSO4 produced more shoot dry weight and had greater leaf area and chlorophyll concentration than those treated with Zn EDTA. In the present study, plant chloride and sodium accumulations were significantly increased and those of potassium (K), calcium (Ca), and magnesium (Mg) strongly decreased as NaCl concentrations in the soil were increased. Moreover, changes in rice shoot Cl?, Na+, and K+ concentrations were primarily affected by the changes in NaCl rate and to a lesser degree were related to Zn levels. The concentrations of Cl? and Na+ associated with 50% shoot growth suppression were greater with Zn‐treated plants than untreated ones, suggesting that Zn fertilization might increase the plant tolerance to high Cl? and Na+ accumulations in rice shoot. Zinc application markedly increased Zn concentration of broad bean shoots, whereas plants grown on NaCl‐treated soil contained significantly less Zn than those grown on NaCl‐untreated soil. Our study showed a consistent increase in praline content and a significant decrease in reducing sugar concentration with increasing salinity and Zn rates. However, Zn‐treated broad bean contained less proline and reducing sugars than Zn‐untreated plants, and the depressing impact of applied Zn as Zn EDTA on reducing sugar concentration was greater than that of ZnSO4. In conclusion, it appears that when broad bean is to be grown in salt‐affected soils, it is highly advisable to supply plants with adequate available Zn.  相似文献   

12.
To study the effect of nitrogen and salinity on growth and chemical composition of pistachio seedlings (cv. ‘Badami’), a greenhouse experiment was conducted. Treatments consisted of four salinity levels [0, 800, 1600, and 2400 mg sodium chloride (NaCl) kg?1 soil], and four nitrogen (N) levels (0, 60, 120, and 180 mg kg?1 soil as urea). Treatments were arranged in a factorial manner in a completely randomized design with three replications. The highest level of nitrogen and salinity decreased leaf and root dry weights. Nitrogen application significantly increased the concentration of shoot N and salinity suppressed shoot N concentration. Salinity and nitrogen fertilization increased shoot and root sodium (Na), calcium (Ca), and magnesium (Mg) concentrations. Nitrogen application increased proline concentration and reducing sugar content. Although salinity levels increased proline concentration a specific trend on reducing sugars content was not observed.  相似文献   

13.
The effects of the interaction between sodium chloride, nitrate, and concentrations on growth and internal ion content of faba bean (Vicia faba L.) plants were studied, to understand the relationship between the above parameters and salt tolerance. Increased salinity substantially reduced the dry weight of roots and shoots and increased the root/shoot biomass ratio. Additional nitrate‐N considerably moderated the salinity effects on these parameters. The promotive effects of nitrate‐N were more pronounced on shoot dry weight. These results suggest that an exogenous supply of nitrate‐N would improve the vegetative growth of V. faba plants by moderating the suppresive effects of salinity. The evolution of the root and shoot content in potassium (K), sodium (Na), magnesium (Mg), calcium (Ca), and nitrogen (N) was monitored during vegetative growth. A high correspondence between total N and Ca content was found. The acquisition of Ca and K in response to salt and nitrate was similar in shoots and roots, whereas Mg uptake showed notable differences in the two organs. In salt‐affected plants, the roots were found to be high in accumulated Na while the shoots exhibited the lowest Na concentration. Potassium accumulation was higher in the shoots. In this way, there was an antagonistic effect between Na and K uptake. Analyses of the nutrient contents in plant organs have provided a data base on salt‐tolerance mechanisms of V. faba plants.  相似文献   

14.
The purpose of this study was to determine the effects of irrigation water salinity on soil nutrient distribution, citrus leaf nutrition and root density. Irrigation water, salinized to an EC of about 0.3,1.6, or 2.5 dS/m using a 3:1 ratio of NaCl:CaCl2 plus uniform weekly applications of liquid fertilizer, was applied through a drip system. Soil samples were taken at depths of 0–15 and 15–30 cm, both directly under the drippers and 45 cm outward from the drippers, near 8‐year old ‘Valencia’ orange trees on either Carrizo citrange or Sour orange rootstocks growing in a Candler fine sand in lysimeter tanks.

In both undisturbed and uniformly mixed soil profiles, soil pH and concentrations of Na, Ca, and P were higher under the dripper than 45 cm outward from the dripper at both depths regardless of salinity level. Soil N and Cl tended to be higher outward from the drippers than near the drippers, except in undisturbed soil at the 0–15 cm depth. Increasing salinity levels in the mixed soil profile not only increased soil EC, Na, Cl, and Ca, but also increased the concentration of P and decreased the concentration of Mg.

Root density of both rootstocks were increased by high salinity. Root densities and organic matter percentages were higher in soil sampled under drippers than that sampled outward from drippers. Leaf nutritional values and responses to salinity were dependent on rootstock as trees on sour orange had higher K and Ca, but lower Mg and Cl than trees on Carrizo. Although there were no nutrient deficiencies, K of trees on Carrizo citrange and Mg of trees on sour orange were rereduced by high salinity. An increase in leaf Ca concentrations when irrigated with salinized irrigation water likely minimized the effects of salt stress.  相似文献   

15.
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.  相似文献   

16.
The effect of NaCl‐salinity on growth responses and tissue mineral content was investigated for two olive (Olea europaea L.) genotypes of different vigor, Leccino and Frantoio. Forty‐day‐old self‐rooted plants were grown for a 60‐day period in a sand culture system supplied with a 1/2 strength Hoagland solution with the addition of 0,12.5,25,50, and 100 mM NaCl. Plants were harvested at 12‐day intervals, and the dry weights of shoot, and principal and lateral roots were evaluated. Relative growth rate (RGR) was also estimated. At the same time, plant tissues were analysed for N, P, K, Ca, Mg, Na, and Cl content.

Growth inhibition by NaCl treatments was greater for Leccino than Frantoio plants. At the end of the experiment, 50 mM NaCl significantly reduced Leccino growth, while negative effects on Frantoio were detected only when using 100 mM NaCl. Leccino always accumulated more Na and Cl in the leaves than Frantoio. In a similar manner, Na/K ratio was always higher in the Leccino leaves compared to the Frantoio leaves. An inverse relationship between NaCl tolerance and vigor of the genotype emerged.  相似文献   

17.
We conducted a study to determine if inoculation with arbuscular mycorrhizal fungi (AMF) would enhance the tolerance of vinca [Catharanthus roseus (L.) G. Don] plants to sodium chloride (NaCl)-induced salinity in irrigation water. Vinca tolerated salinity levels up to 40 mM. Chlorophyll concentration, proline synthesis, and total antioxidant activity were increased with saline irrigation, while leaf potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), and boron (B) content decreased, suggesting a detrimental salinity effect. Despite the limited effect of increasing salinity on N content, NaCl-stressed vinca plants showed a marked decrease in nitrate reductase activity, which was associated with decreased leaf K and Fe total content. Mycorrhizal inoculation resulted in reduced growth when compared to non-AMF plants, regardless of salinity level. The K/sodium (Na) ratio decreased dramatically with increasing salinity regardless of AMF treatment. Suggesting, that the AMF isolate was not able to selectively uptake K and Ca, and avoid uptake of Na.  相似文献   

18.
Two lines of sunflower (Helianthrus annuus L.), a salt‐tolerant Euroflor and a salt‐sensitive SMH‐24, were grown for three weeks in sand culture containing 0 or 150 mol/m3 NaCl in full strength Hoagland nutrient solution. Distribution of cations in the leaves of varying ages was determined. The older leaves of SMH‐24 contained more sodium (Na) in the laminae than the younger leaves at the salt treatment, whereas laminae of leaves of varying ages of Euroflor maintained Na concentration almost uniform. Distribution of potassium (K), calcium (Ca), and magnesium (Mg) in the laminae was strongly age‐dependent in both lines, i.e., the older leaves contained greater concentrations of these cations than did the younger leaves. The lines did not differ in concentrations of the three cations. The older leaves of SMH‐24 had significantly lower K/Na ratios than those of Euroflor, but the lines did not differ in lamina Ca/Na ratios. It is concluded that distribution of K, Ca, and Mg in the leaf laminae is age‐dependent. Salt‐tolerance in sunflower is related to exclusion of Na in the leaf laminae and to maintenance of almost uniform concentrations of this ion in leaves of all ages.  相似文献   

19.
Two experiments were conducted to determine if improved nutrient uptake increases salinity tolerance of cotton (Gossypium hirsutum L.). A transgenic cotton line (CMO3) with increased salt tolerance and its wild line (SM3) were grown in pots containing substrate (peat:vermiculite = 1:1, v/v) in the first experiment, while cotton (‘SCRC 28’) was cultured in hydroponics with a split-root system in the second experiment. Contents of essential nutrient elements and Na+ in plant tissues, leaf photosynthesis (Pn) and chlorophyll (Chl) concentration and plant biomass were determined after salinity [sodium chloride (NaCl)] treatment in both experiments. In the first experiment, salinity stress with 150 mM NaCl reduced plant biomass and photosynthesis (Pn) of both SM3 and CMO3 compared with their non-stressed controls, but the CMO3 suffered significantly lower reductions than SM3, suggesting an increased salinity tolerance of CMO3 relative to SM3. Total uptake and contents of main nutrient elements [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn)] in CMO3 were higher than those in SM3. Also, less sodium (Na+) accumulation and lower extreme ratios of Na/N, Na/P, Na/K, Na/Ca, Na/Mg, Na/Fe, Na/Mn, Na/Cu, and Na/Zn were observed in CMO3 than in SM3. Increased salt tolerance in transgenic AhCMO cotton was probably attributed to its superior nutrient uptake compared with SM3. In the second experiment, the non-stressed root half fed with moderate level of nutrient solution and salt-stressed half fed with low level of nutrient solution (CMN/SLN) exhibited higher salinity tolerance than salt-stressed root half fed with moderate level of nutrient solution and non-stressed root half fed with low nutrient solution (CLN/SMN). Plants absorbed more nutrients but less Na+ under CMN/SLN than CLN/SMN. The overall results suggest that improved nutrient uptake played an important role in the enhanced salt tolerance of cotton.  相似文献   

20.
Diagnosing nutrient insufficiencies or toxicities in sorghum through foliar analysis is still unusual and mainly used for grain sorghum. The influences of the combinations of four nitrogen (N) rates with three sodium chloride (NaCl) rates on the leaf N, phosphorus (P), calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na) concentrations of sweet sorghum [Sorghum bicolor (L.) Moench ssp. saccharatum], cropped for ethanol production, and on biomass and sugar yields were evaluated in three consecutive years of an experiment established on a Eutric Fluvisol equipped with a trickle irrigation system (“triple emitter source”). The relationships among leaf nutrient concentrations, dry matter, and sugar yields were also examined. Nitrogen, much more than salinity, affected leaf nutrient concentration, stem dry weight, and sugar yield. Leaf N concentration was the best indicator for predicting sugar production of sweet sorghum.  相似文献   

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