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1.
Abstract

Biological bacteria alleviate the adverse effects of osmotic stress under salinity conditions by different processes. In the present research, factorial test was performed based on complete randomized block design and the effect of two types of bacteria azotobacter and azospirillum and five salinity levels of 0, 4, 6, 8, 12 dS/m in nutrients, fresh and dry weights of the plants, amount of auxin, proline, tillering, and quality of tall fescue were studied. Results showed that the highest dry weight of shoots, dry, and fresh weights of the roots, tillering and nitrogen have been observed in 8 dS/m salinity?+?azotobacter treatment. The highest fresh weight of shoot was seen in 4 dS/m salinity treatment without bacteria. The highest quality of tall fescue was seen in 4 and 6 dS/m salinity treatments without bacteria, the highest amount of sodium was seen in 12 dS/m salinity?+?azospirillum treatment, and the highest amount of auxin contents of roots, stems and the highest amount of phosphorus were obtained in the control?+?azospirillum treatment. Also, the highest amount of potassium (K) and the lowest amount of nitrogen (N) and sodium (Na) were seen in the control treatment without bacteria. The lowest amount of potassium and the lowest fresh and dry weights of the roots were seen in 12 dS/m salinity?+?azotobacter treatment. The lowest fresh and dry weights of the shoots were seen in 4 dS/m salinity?+?azospirillum treatment and 6 dS/m salinity treatment without bacteria. The lowest amount of proline was obtained in control?+?azotobacter treatment. The lowest amount of phosphorus and stem’s auxin and also the highest amount of proline were obtained in 12 dS/m salinity treatment without bacteria. Generally, growth-inducing bacteria reduces the adverse effects of salinity stress and improves quality of tall fescue.  相似文献   

2.
The effects of five salinity levels and four copper levels on growth and chemical composition of ‘Ghazvini, pistachio seedlings were studied under greenhouse conditions in a completely randomized design with three replications. Leaf area, stem height, shoot and root dry weights were determined on 24th week after planting. Copper (Cu), phosphorus (P), sodium (Na), and chlorine (Cl) total uptake in shoot and root of plant were measured. The results showed that salinity decreased growth parameters. Low levels of Cu application had no significant effect on leaf area, shoot and root dry weights while decreased stem height. The highest level of Cu (7.5 mg Cu kg?1 soil) significantly increased leaf area and shoot dry weight but decreased stem height. Salinity decreased Cu and P uptake in the shoot and root, but increased total sodium and chloride uptake. Cu application increased shoot total P uptake and decreased root total Na uptake.  相似文献   

3.
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   

4.
The present research was conducted to study the responses of ‘Malas–e–Saveh’ (M) and ‘Shishe–Kab’ (Sh) Iranian pomegranates to sodium chloride (NaCl) stress under greenhouse and field conditions. Treatments included waters electrical conductivity (EC = 1.5, 3, 6, 9 and 12 dS m?1 for greenhouse) and (EC = 1.05 as control, 4.61 and 7.46 dS m?1 for field studies). Interactive effects of salinity × variety indicated the highest chlorophyll and leaf potassium concentration, and the lowest leaf chloride and sodium in control under greenhouse study. Non-photochemical quenching, effective quantum yield of photochemical energy conversion in PSII reduced under the highest salinity level in field, however, basal quantum yield of non-photochemical processes in PSII increased in the highest salinity. Sodium and chloride increased with increased in salinity. Calcium, magnesium and iron significantly decreased with increased in salinity. It seems that there are differences between pomegranate cultivars and Malas-e-Saveh is more tolerant compared with Shishe Kab.  相似文献   

5.
We investigated the effect of exogenously applied silicon (Si) on the growth and physiological attributes of wheat grown under sodium chloride salinity stress in two independent experiments. In the first experiment, two wheat genotypes SARC-3 (salt tolerant) and Auqab 2000 (salt sensitive) were grown in nutrient solution containing 0 and 100 mM sodium chloride supplemented with 2 mM Si or not. Salinity stress substantially reduced shoot and root dry matter in both genotypes; nonetheless, reduction in shoot dry weight was (2.6-fold) lower in SARC-3 than in Auqab 2000 (5-fold). Application of Si increased shoot and root dry weight and plant water contents in both normal and saline conditions. Shoot Na+ and Na+:K+ ratio also decreased with Si application under stress conditions. In the second experiment, both genotypes were grown in normal nutrient solution with and without 2 mM Si. After 12 days, seedlings were transferred to 1-l plastic pots and 150 mM sodium chloride salinity stress was imposed for 10 days to all pots. Shoot growth, chlorophyll content and membrane permeability were improved by Si application. Improved growth of salt-stressed wheat by Si application was mainly attributed to improved plant water contents in shoots, chlorophyll content, decreased Na+ and increased K+ concentrations in shoots as well as maintained membrane permeability.  相似文献   

6.
Banebaghi is considered a natural hybrid in Pistacia genus that can be used as rootstock for pistachio. In order to study the effects of salinity stress on growth indices, physiological parameters and element concentration in Banebaghi, an experiment was arranged as a factorial in completely randomized design (CRD). Factors were salinity of irrigation water (0, 60 and 120 mM of sodium chloride, calcium chloride, magnesium chloride, respectively), growth type (mutica growth type and pistachio growth type) and stem height (stem height lower half of the plant and stem height upper half of the plant) with four replications. Our results showed that salinity reduced vegetative parameters, SPAD index, leaf relative water content (RWC) and water use efficiency (WUE). Shoot dry weight of seedlings in both heights, decreased at the salinity level of 120 mM, at about 60% compared with control. At the highest level of salinity (120 mM), seedlings with a height lower half of the plant had lower reduction in the fresh and dry weight of the root and showed more resistance to the salinity stress because of maintaining RWC of leaves and high levels of potassium and calcium in the shoot. Salinity increased sodium (Na) concentration of shoot and root in both growth types: mutica and pistachio. Seedlings with pistachio growth type and a height upper half of the plant and seedlings with mutica growth type and a height lower half of the plant had more resistance to salinity stress.  相似文献   

7.
The effects of nutrient or sodium chloride (NaCl) salinity on pepper grown in closed soilless culture systems were studied. A control (2 dS m?1) and two saline nutrient solutions (4 dS m?1) differing in the salt sources (fertilizers or NaCl) were studied. Shoot biomass production as well as total and marketable yield were more affected by NaCl than nutrient salinity. Fruit dry matter and total soluble solids increased in both salinity treatments compared to the control. Total phenol content rose slightly (10%) with NaCl salinity, while the concentration of carotenoids was enhanced by 40% with NaCl compared to the control and nutrient salinity. The results showed that the response of pepper to salinity is both osmotic and ion specific, but a more negative effect was recorded under NaCl stress. Moreover, the highest content of antioxidant compounds in NaCl treated fruits may indicate that NaCl caused more stressful conditions than nutrient salinity.  相似文献   

8.
Strawberry is listed as the most salt sensitive fruit crop in comprehensive salt tolerance data bases. Recently, concerns have arisen regarding declining quality of irrigation waters available to coastal strawberry growers in southern and central California. Over time, the waters have become more saline, with increasing sodium (Na+) and chloride (Cl?). Due to the apparent extreme Cl? sensitivity of strawberry, the rising Cl? levels in the irrigation waters are of particular importance. In order to establish the specific ion causing yield reduction in strawberry, cultivars ‘Ventana’ and ‘Camarosa’ were grown in twenty-four outdoor sand tanks at the ARS-USDA U. S. Salinity Laboratory in Riverside, CA and irrigated with waters containing a complete nutrient solution plus Cl? salts of calcium (Ca2+), magnesium (Mg2+), Na+, and potassium (K+). Six salinity treatments were imposed with electric conductivities (EC) = 0.835, 1.05, 1.28, 1.48, 1.71, and 2.24 dS m?1, and were replicated four times. Fresh and dry weights of ‘Camarosa’ shoots and roots were significantly higher than those of ‘Ventana’ at all salinity levels. Marketable yield of ‘Camarosa’ fruit decreased from 770 to 360 g/plant as salinity increased and was lower at all salinity levels than the yield from the less vigorous ‘Ventana’ plants. ‘Ventana’ berry yield decreased from 925 to 705 g/plant as salinity increased from 0.835 to 2.24 dS m?1. Relative yield of ‘Camarosa’ decreased 43% for each unit increase in salinity once irrigation water salinity exceeded 0.80 dS m?1. Relative ‘Ventana’ yield was unaffected by irrigation water salinity up to 1.71 dS m?1, and thereafter, for each additional unit increase in salinity, yield was reduced 61%. Both cultivars appeared to possess an exclusion mechanism whereby Na+ was sequestered in the roots, and Na+ transport to blade, petiole and fruit tissues was limited. Chloride content of the plant organs increased as salinity increased to 2.24 dS m?1 and substrate Cl increased from 0.1 to13 mmolcL?1. Chloride was highest in the roots, followed by the leaves, petioles and fruit. Based on plant ion relations and relative fruit yield, we determined that, over the range of salinity levels studied, specific ion toxicity exists with respect to Cl?, rather than to Na+ ions, and, further, that the salt tolerance threshold is lower for ‘Camarosa’ than for ‘Ventana’.  相似文献   

9.
Salinity is one of the major environmental stressors which has deleterious effects on the growth, development, and yield of crops. Because of the gradual increase in soil and water salinity in the East Azarbaijan, Iran, Tanacetum balsamita L. cultivation in this region has always been associated with many problems. To study the effect of foliar spray of iron sulfate (FeSO4) (0, 750, and 1500 mg L?1) under sodium chloride (NaCl) salinity (0, 50, and 100 mM) on some physiological characteristics of Tanacetum balsamita L. plants, an experiment was conducted as a factorial based on complete randomized block design with three replications. Total soluble solids (TSS) and essential oil contents were significantly affected by the interaction effects of FeSO4 foliar application and salinity levels. The highest TSS and essential oil content were found in the plants under NaCl0 × FeSO4 1500 mg L?1 treatment combination. Leaf length, leaf fresh and dry weights were influenced by both Fe foliar application and salinity levels. Foliar application of iron (Fe) positively affected leaf length, leaves fresh and dry weights, root fresh and dry weights and peroxidase (POD) content, especially at 1500 mg L?1. Other traits such as leaf length, leaf fresh and dry weights, malondialdehyde (MDA), POD and catalase (CAT) contents were influenced by salinity levels. For POD, MDA, and CAT contents, the highest values were recorded with NaCl 50 and 100. The highest values of leaf length, leaf fresh and dry weights were found in the control plants.  相似文献   

10.
□ Growth and nutrient acquisition of tomato (Lycopersicon esculentum L.) cv ‘Amani’ were studied under induced salt stress in Hoagland's solution. The plants were treated for 37 days with salinity induced by incorporating different concentrations [0.0 (control), 50, 100, 150, or 200 mM] of sodium chloride (NaCl) to the nutrient solution. Slight reduction was obtained in growth represented by (shoot length and number, leaf number, and dry weight) when seedlings were directly exposed to NaCl stress from 0.0 to 100 mM. At higher concentrations (150 or 200 mM), growth parameters were adversely affected and seedlings died thereafter. Elevated salinity significantly reduced crude protein and fiber in shoots and roots. Tomato shoot and root contents of potassium (K), iron (Fe), and ash were reduced significantly in response to increased levels of salinity. Tissue contents of sodium (Na) and chloride (Cl) increased with elevated salinity treatments.  相似文献   

11.
□ Plants from 60-day-old Lime Thyme (Thymus citriodorus) cuttings were potted in a medium of coconut fiber and peat moss and were treated with three different nutrient solutions: T1, T2, and T3. T1 was a standard nutrient solution; T2 was incremented with macronutrients up to an electrical conductivity (EC) of 2.8 dS m?1; and T3 was the same as T1 but incremented up to an EC of 2.8 dS m?1 with sodium chloride. The plants were then grown for 90 days in a greenhouse with natural daylight in Almería, Spain. Root growth was not affected by the treatments. The dry weight of the leaves and the total dry weight of the plants benefited from the salinity. The specific salinity of the sodium chloride negatively affected growth compared to the same salinity in the complete nutrient solution.  相似文献   

12.
To determine the effects of irrigation water quality, plants were irrigated with normal potable water [0.25 dS m?1 electrical conductivity (EC), 25 mg L?1 sodium (Na), 55 mg L?1 chloride (Cl)], treated effluent (0.94 dS m?1 EC, 122 mg L?1 Na, 143 mg L?1 Cl) and saline water with low salinity (1.24 dS m?1 EC, 144 mg L?1 Na and 358 mg L?1 Cl) and high salinity (2.19 dS m?1 EC, 264 mg L ?1Na and 662 mg L?1 Cl) for snow peas, and high salinity (3.07 dS m?1 EC, 383 mg L?1 Na and 965 mg L?1 Cl) and very high salinity (5.83 dS m?1 EC, 741 mg L?1 Na and 1876 mg L?1 Cl) for celery. The greater salts build up in the soil and ion toxicity (Cl and Na) with saline water irrigation contributed to significantly greater reduction in root and shoot biomass, water use, yield and water productivity (yield kg kL?1 of water used) of snow peas and celery compared with treated effluent and potable water irrigation. There was 8%, 56% and 74% reduction in celery yield respectively with treated effluent, high salinity and very high salinity saline water irrigation compared with potable water irrigation. The Na concentration in snow peas shoots increased by 54%, 234% and 501% with treated effluent, low and high salinity saline water irrigation. Similarly, the increases in Na concentration in celery shoots were 19%, 35% and 82%. The treated effluent irrigation also resulted in a significant increase in soil EC, nitrogen (N) and phosphorus (P) content compared with potable water irrigation. The heavy metals besides salts build up appears to have contributed to yield reductions with treated effluent irrigation. The study reveals strong implications for the use of saline water and treated effluent for irrigation of snow peas and celery. The salt build up within the root zone and soil environment would be critical in the long-run with the use of saline water and treated effluent for irrigation of crops. To minimize the salinity level in rhizosphere, an alternate irrigation of potable water with treated effluent or low salinity level water may be better option.  相似文献   

13.
Cucumber (Cucumis sativus L. cv. Lvyuan4) seedlings were either noninoculated or inoculated with four bacteria to study the interactions of salinity in saline soil, cucumber, and bacteria. The seedlings were grown under controlled conditions in pots; the solutions of 100, 200, 400, and 600 mM sodium chloride (NaCl) and bacterial broth were added to the soils. Deionized water was used as control. There were nine treatments in the experiment. Each treatment contained three replications and each replication represented six plants. After 14 days of treatment, morphological characteristics, fresh and dry weights, chlorophyll, soluble sugar, malonaldehyde, proline, nutrient elements, and sodium (Na+) and chloride (Cl?) contents in plants and soils were calculated. Soil salinity inhibited seedlings growth, but low concentration of NaCl promoted plant growth. Soil microbial biomass decreased in saline soils and increased in inoculated treatments. Bacteria had the role of promoting growth and protecting plants against salinity. Bacteria accelerated Na+ and Cl? uptake markedly.  相似文献   

14.
Low organic matter and high salinity are widespread throughout all pistachio (Pistacia vera L.) growing areas of Iran. The objective of this study was conducted to investigate effect of pistachio waste (PW), salinity, and their interaction on growth and chemical composition of pistachio seedlings. The experiment was carried out based on factorial and completely randomized design (CRD) with four replications. The treatments contained salinity in three levels [0, 1000, and 2000 mg sodium chloride (NaCl) kg?1 soil] and PW in three levels (0, 3, and 6%). The results indicated that salinity application decreased leaf, stem, and root dry weights; leaf area; and length of stem, while this effect diminished with 3% PW application. Application of PW at the rate of 6% significantly reduced these parameters and accelerated effect of salinity levels. Leaf, stem, and root potassium (K) and phosphorus (P) concentrations were decreased by salinity application, while leaf, stem, and root sodium (Na) concentrations was increased. However, PW application increased these nutrient concentrations in the leaves, stem, and root, but significantly diminished the effect of salinity. The results showed that proline accumulation and reducing sugar content in the leaves were increased by salinity, PW, and their combination application. The results suggest that application of PW, especially at rate of 3%, can reduce some adverse effects of salinity on growth and chemical composition of pistachio seedlings.  相似文献   

15.
Application of plant growth regulator (PGR) may alleviate some negative effects of environmental stresses such as salinity. A controlled environment experiment was conducted to study barley (Hordeum vulgare L. cv. Reyhane) growth, yield, antioxidant enzymes and ions accumulation affected by PGRs under salinity stress conditions at Shiraz University during 2012. The treatments were PGRs at four levels—water (as control), cycocel (CCC, 19 mM), salicylic acid (SA, 1 mM), and jasmonic acid (JA, 0.5 mM)—and four salinity levels—no stress (0.67 dS m?1, as control), 5, 10, and 15 dS m?1, which were arranged in a factorial experiment based on completely randomized design with four replicates. The results showed that salinity stress significantly decreased plant height, peduncle length, leaf area, ear length, grain number, dry weight, grain yield, harvest index, potassium (K+) accumulation, and potassium/sodium (K+/Na+) concentration ratio, which were closely associated with stress severity. However, PGRs compensated some of these negative effects, so that SA foliar application had the most ameliorative effect. Salt stress also increased Na+ accumulation as well as the activity of peroxidase, catalase, and superoxide dismutase (SOD). Since ion discrimination and enhanced antioxidant enzymes are associated with salt tolerance, in this experiment PGRs application might have enhanced K+ accumulation and antioxidant enzyme activity. The activity of SOD and K+/Na+ ratio were found to be useful in salt tolerance manipulation in barley plants.  相似文献   

16.
Salinity is the major environmental stress that affects the growth and productivity of plants. The present study was conducted to determine the effect of salinity on growth and ions uptake by moringa (Moringa oleifera L.) plant. The experiment was carried out in two phases. Initially, a germination test was conducted in the laboratory under the different salinity levels (control, 5, 10, 15, and 20 dS m?1) and found that moringa seeds were germinated only at 5 and 10 dS m?1 salinity levels, and no germination occurred at higher salinity levels (15 and 20 dS m?1). The experiment was laid out in a completely randomized design (CRD) with five replications. In the second phase, three-week old nursery grown plants of moringa were shifted in pots under the five salinity levels (control, 5, 10, 15, and 20 dS m?1). The experiment was laid out in CRD and replicated four times. In pot experiment, the root, shoot length, and dry weights were significantly affected by increasing the salinity levels. The uptake of K+ and Ca2+ was highly affected at different salinity levels as compared to control and Na+ ions accumulation was higher in roots rather than shoot. The results reveal that moringa plant can germinate, survive, and can be cultivated in areas with moderate saline condition.  相似文献   

17.
A greenhouse study was conducted to evaluate effects of phosphorus (P) levels (0, 50 and 100 mg kg?1 soil) under saline (0, 1000 and 2000 mg sodium chloride (NaCl) kg?1 soil) conditions on growth and chemical composition of pistachio seedlings (Pistacia vera L.) cv. ‘Badami-zarand’ in a completely randomized design (CRD) with four replications. Results showed that salinity application decreased leaf, stem, and root dry weights, number of leaf, length of stem and leaf area, while this effect diminished with P fertilization. By increasing salinity levels, all of the nutrients concentration in leaf, stem and root except sodium (Na) content were reduced. P application increased P and potassium (K) concentrations in the leaves, stem and root, while decreased Na and Zinc (Zn) leaf, stem and root concentrations. However, the results indicated that proline accumulation and reducing sugar content were increased by salinity, P and their interaction application. The results suggest that fertilization of phosphorus can diminish some adverse effects of high salinity on growth and chemical composition of pistachio seedlings.  相似文献   

18.
Effect of water salinity was studied in different Matricaria recutita L. genotypes (Isfahan, Ahvaz, and Shiraz) to understand their protective mechanisms and agronomic performance. Based on a split-plot design arranged in a randomized complete-block consisted of four salinity levels as the main plot and three genotypes as the subplots with three replications this field experiment was conducted in 36 plots with 3 m2 space in the Isfahan Center for Research of Agricultural Science and Natural Resources during 2014–2015. The findings showed that the three genotypes differed in resistance to salinity and tolerance mechanisms. They have evolved different physiological, morphological, and biochemical adaptations to salt stress. The Ahvaz genotype in the absence of salt, the Isfahan genotype at 6, and the Shiraz genotype at 9 and 12 dS m?1 sodium chloride (NaCl) were desirable, taking both quantity and quality into consideration. While preserving shoot growth, the Isfahan genotype was more tolerant to 6 dS m?1 NaCl most likely due to peroxidase activity. The resistance of the Shiraz genotype is associated with root growth stimulation at 9 and Na compartmentation in root at 12 dS m?1 NaCl. The Isfahan genotype had the highest oil and chamazulene content, which was not affected by salinity. The Shiraz genotype in the control treatment, the Isfahan genotype at 6 and 9 and the Ahavaz genotype at 12 dS m?1 NaCl synthesized higher flavonoid compounds.  相似文献   

19.
Suaeda aegyptiaca is an important native annual halophyte in salt-affected soils around coastal areas of the Persian Gulf. In order to study the effects of different levels of saturation paste soil salinity (10, 20, 40, 60, and 80 dS m?1) and nitrogen supply (25, 50, and 75 mg kg?1 N as urea) on growth and physiological characteristic of S. aegyptiaca, a greenhouse factorial experiment in completely randomized design was conducted with three replications. Salinity treatments were established after early growth of plants and nitrogen was applied in two steps. Results showed that increasing salinity up to 20 dS m?1 led to increase in dry weight (DW) of plants and this decreased by increasing salinity. Also, DW of plants was significantly increased by application of 75 mg kg?1 nitrogen. Increasing salinity significantly decreased plant height, chlorophyll index, and total nitrogen content; while proline content and total soluble solids (TSS) were significantly increased. The electrolyte leakage (EL) and sodium concentration were increased under salinity stress. However, further increase in salinity decreased these two parameters. By increasing the nitrogen levels, relative water content (RWC), chlorophyll index, proline, and total nitrogen contents were increased, whereas EL was decreased.  相似文献   

20.
Arbuscular mycorrhizal (AM) fungi alleviate the unfavorable effects of salinity stress on plant growth. A pot study was conducted to determine the effects of AM fungi and salt on growth and some physiological parameters of Citrus jambheri rootstock. Four levels of salinity (2, 4, 6, and 8 dS m?1 as NaCl) and three mycorrhizal treatments (Glomus etunicatum, Glomus intraradices and non-mycorrhizal (NM) control) were used. As salinity increased, all measured characteristics of plants after 4.5-month growth except Na uptake, proline content, and electrolyte leakage decreased. Shoot dry weight and K uptake were significantly higher in G. intraradices-colonized seedlings than NM controls at all salinity levels. Root dry weight and shoot P uptake were significantly higher in G. etunicatum-colonized seedlings than NM controls at all salinity levels. G. intraradices-colonized seedlings had significantly higher proline content than NM controls and G. etunicatum-colonized seedlings at salinity levels of 4, 6 and 8 dS m?1. The electrolyte leakage percentage was significantly lower in G. intraradices-colonized seedlings than NM controls at all salinity levels. The data demonstrated that mycorrhizal citrus seedlings exhibited greater tolerance to salt stress than NM seedlings and the enhanced proline content seems to be one of the mechanisms involved.  相似文献   

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