Mineral Nutrient Acquisition by Cotton Cultivars Grown under Salt Stress

Physiological responses were investigated in two cotton cultivars grown at various concentrations of sodium chloride (NaCl) in order to determine the degree of the tolerance of the cultivars to salt stress and understand the physiological responses with respect to utilization of mineral nutrients. After germination of the seeds of cotton cultivars, they were transferred into standard pots with 210 g sterilized compost and watered with 30 ml Hoagland’s solution containing different concentrations (0, 50, 100, 200, and 400 mM) of NaCl at two-day intervals for 3 months. Growth parameters were measured and the mineral nutrient analyses were done using inductively coupled plasma optical emission spectrometry (ICP-OES, Thermo Fisher Scientific, Waltman, MA). It was observed that plant growth and mineral nutritional status of both cultivars were altered extensively in those grown with NaCl. Excess NaCl reduces the concentrations of certain mineral nutrients and increases that of others, the patterns depending on the mineral nutrient and the plant part and varieties being compared to the control.     

多效唑和氯化胆碱对香蕉试管苗生长的影响

以香蕉威廉斯（Ｗｉｌｉａｍｓ）无根的试管芽为材料,分别在附加不同浓度的多效唑（ＭＥＴ）及氯化胆碱（ＣＣ）的ＭＳ培养基上进行培养。结果表明：ＭＥＴ对香蕉试管苗具有明显的抑制纵向伸长,促进横生生长的作用。当处理的ＭＥＴ浓度为１ｍｇ·Ｌ－１时,试管苗矮化适中,叶片变短增厚挺立,叶色深绿,根系粗短,整株与对照相比显得十分茁壮鲜绿。以５００ｍｇ·Ｌ－１浓度的ＣＣ处理时,可显著提高植株高度,刺激发根和增加鲜重。     

Sodium Chloride Effects on Water and Nutrient Uptake Efficiency in Sarcocornia fruticosa Containerized Production

The ability to produce native plants well adapted to the saline conditions without the production of nutrient-rich runoff will be a boon to nurseries hoping to reduce their environmental contamination impact and water use while at the same time producing quality plants to be used in the restoration of saline lands. Sarcocornia fruticosa plants were grown for 8 weeks in plastic containers with a source of sphagnum peat moss and perlite (80:20 v/v) to evaluate the effect of two salinity levels (2.0 (low-salinity treatment) and 7.5 dS m^?1 (high-salinity treatment)) on plant growth, nutrient concentration in leachate and water and nutrient uptake efficiency and their losses. Leachate was collected to determine the runoff volume and composition, which included nitrate-nitrogen (NO₃^–N), phosphate-phosphorus (PO₄^3–P) and potassium (K⁺) concentrations. Plant dry weight (DW) and nutrient content were determined in plants at the beginning and at the end of the experiment to establish the nutrient balance. Increasing salinity levels of irrigation water did not reduce either the plant DW or the water-use efficiency (WUE), but increased the volume of leachate per plant. The nutrient concentrations in leachates without significant differences between salt treatments exceeded the thresholds established by environmental guidelines, leading to a great risk of pollution. Based on nutrient balance, the irrigation with a higher salinity level reduced the plant nutrient uptake efficiency (10%, 18% and 12% for nitrogen (N), phosphorus (P) and potassium (K), respectively) and increased the nutrient losses (6% N, 7% P and 8% K), resulting in the recommendation to grow this species with the low salinity level based on the highest nutrient-use efficiency and the lowest levels of nutrient losses.     

Effect of Sodium Chloride on Growth,Nutrient Accumulation,and Nitrogen Fixation of Common Bean Plants in Symbiosis with Isogenic Strains

The effect of sodium chloride (NaCl)-salinity on growth responses and tissues organic solutes and mineral content was investigated in common bean plants inoculated with salt-tolerant Rhizobium tropici wild-type strain CIAT899 and four mutant derivatives having decreased salt-tolerance (DST). Under non-saline conditions two mutants formed partially effective (HB10, HB12) and another two almost ineffective (HB8, HB13) nodules. A great variation of NaCl tolerance in the different symbiosis tested was observed at harvest, 32 day after planting. Common bean plant responded to salinity by decreasing the content of dry plant biomass, nodule number and the nitrogen fixation, and increasing the root to shoot ratio. The salt dose of 25 mM produced an increase of total soluble sugar and free amino acids content. This result suggest that these metabolites might be related with a nodule osmotic adjustment response under saline conditions, however cannot be excluded that the increase of amino acids content could be a consequence of protein degradation. In the other hand, sodium, calcium and phosphorus contents in shoot increased under the saline treatments. Potassium (K) and calcium (Ca) contents, unlike phosphorus (P) content, in shoot were not related with the symbiotic efficiency of mutant, however the decrease of P content suggest that these symbioses have limited their P absorption process independently of the saline treatment. NaCl tolerance associated with a retention of sodium and maintenance of potassium selectivity seem to be a strategy used for the salt stressed common bean plants in symbiosis assayed here.     

盐分胁迫对菠菜生长和吸氮量的影响

为了研究盐分胁迫对菠菜生长和吸氮量的交互影响,在光培养室内开展了土柱栽培试验。试验设置3个灌溉水含盐量水平:0.87dSm-(1淡水,S0)、2.0dSm-(1盐分胁迫,S1)和5.0dSm-(1盐分胁迫,S2),2个氮肥水平:100kg Nhm-2(N1)和300kgNhm-(2N2)。本试验条件下,菠菜生育期为54天。在前44天,随着盐分胁迫程度增加,菠菜相对生长速率(relative growth rate,RGR)降低,其中在33~44天时,N1水平下,S0处理的RGR最大,为1.30×10-1gg-1day-1;在生育期的后10天,随着盐分胁迫增加,RGR升高。盐分胁迫导致菠菜吸氮量和干物质重下降。盐分胁迫和氮肥的交互影响使菠菜吸氮量降低47.02mgpot-1。菠菜吸氮量是其生长时间的二次函数。该研究表明,S2水平下,菠菜生育前期施肥量高,抑制作物生长。     

Effect of Sodium Chloride Salinity on Growth and Ion Accumulation in Some Halophytes

Abstract

Effects of salinity on biomass production, water content, and ion accumulation pattern in Atriplex amnicola P. G. Wilson, Atriplex calotheca L., Atriplex hortensis L., Chenopodium album L., Salsola kali L., and Suaeda nudiflora Moq. (all Chenopodiaceae) have been studied. The plants survived and exhibited no toxicity symptoms up to 6000 mg L^?1 NaCl treatment. Ion composition was variable in plants grown under different salinity treatments. Salinity, except in Suaeda nudiflora where the least biomass was produced in control, affected all other species negatively, and they produced the least biomass at high salinity treatment. Shoot water content of Suaeda nudiflora and Chenopodium album increased significantly in response to salinity. Among all the species examined here, maximum sodium (Na⁺) accumulation was recorded for Suaeda nudiflora, and it increased with the increasing salinity. This study concluded that among all the species tested, Suaeda nudiflora was most suitable plant for bioremediation of salt‐contaminated soils.     

Growth,Chlorophyll, and Cation Concentration of Tetraploid Wheat on a Solution High in Sodium Chloride Salt: Hulled Versus Free-Threshing Genotypes

Based on the literature, under-utilized hulled wheats could be tolerant to some harsh environmental conditions. The effect of salt stress on chlorophyll content, leaf area, dry weight, and ion concentrations in eight genotypes of tetraploid wheat (Triticum turgidum) using a three-replicate completely random design indoor experiment was studied. These genotypes included six hulled wheat (HW), T. turgidum subspp. Dicoccum, and two free-threshing wheat (FTW), T. turgidum subspp. durum. Salt stress was induced by adding sodium chloride (NaCl) to a hydroponic medium to 40, 80, and 120 mM, in addition to control. Salinity reduced leaf content of chlorophyll a (chl-a) at 120 mM but had not significant effect on chlorophyll b (chl-b) content. Salt stress decreased plant leaf area by nearly 63%. Plant top dry weight declined by 52% with increasing salinity to 120 mM level. Plant top calcium (Ca²⁺) content was not affected, whereas plant top sodium (Na⁺) concentration increased and potassium (K⁺) and magnesium (Mg⁺) concentration decreased with increasing salinity, averaged over genotypes. No significant interaction of genotype × salinity was detected for traits studied in this experiment. When contrasted as two groups of genotypes, i.e., HW vs. FTW, the former group suffered more severe decreases in terms of chl-a, chl-b, leaf area, dry weight, and Mg²⁺ concentration and a more pronounced increase in Na⁺ compared to the FTW. Overall, no evidence of salt tolerance was found for hulled tetraploid wheats of central Iran.     

Sodium Chloride Timing and Length of Exposure Affect Onion Growth and Flavor

ABSTRACT

This study investigated how sequentially exposing plants to sodium chloride (NaCl) would affect growth and the flavor quality of onion (Allium cepaL.) bulbs at harvest. In a greenhouse experiment beginning 74 d before harvest, 100 mM concentrations of NaCl were applied at biweekly intervals to onions growing in nutrient solutions. At harvest, fresh weights (FW) were measured and the bulbs were analyzed for soluble solids content (SSC), bulb pungency as measured by total pyruvate (TPY), bulb sulfur (S) and sulfate (SO₄ ^?2) accumulation, flavor precursors, and their biosynthetic intermediates. Bulb and leaf FW decreased linearly the earlier NaCl was added during plant growth and development. While total bulb S was significantly affected by sequential addition of NaCl, bulb SO₄ ^?2 was unaffected. Bulb pungency was significantly reduced by NaCl, especially when NaCl was introduced during early bulb development. NaCl generally reduced flavor precursor accumulation in a quadratic response, with the greatest depression occurring when plants were exposed to NaCl beginning in the early stages of bulbing. Significant reductions in plant growth and changes in the S-compounds associated with flavor suggested that the duration and timing of NaCl exposure are important in onion.     

种子引发剂氯化胆碱和吲哚丁酸钾对盐胁迫下水稻幼苗生长和生理特性的影响

为探讨种子引发剂对盐胁迫下水稻幼苗生长及生理特性的影响机制,以杂交稻湘两优900和常规稻黄华占为材料,研究引发剂氯化胆碱(CC)和吲哚丁酸钾(IBAK)对盐胁迫下水稻幼苗生长、光合特性、抗氧化代谢及渗透调节的影响。结果表明,盐胁迫抑制水稻幼苗生长,3.0 mg·L^-1CC和1.0 mg·L^-1IBAK为缓解盐胁迫对水稻幼苗生长抑制的适宜引发浓度,添加引发剂CC的湘两优900根干重显著增加9.64%,而添加引发剂CC和IBAK的黄华占根系总长度、叶面积、地上干重、根干重、壮苗指数分别显著增加24.78%和14.39%、43.06%和36.33%、11.45%和7.43%、34.60%和28.62%、41.89%和33.55%。引发剂CC和IBAK处理可显著提高盐胁迫下两品种水稻叶片的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)和叶绿素含量;激活超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性;同时增加抗坏血酸(AsA)、谷胱甘肽(GSH)、可溶性蛋白和脯氨酸含量;抑制活性氧积累,降...     

Effect of Salt Stress and Manganese Supply on Growth of Barley Seedlings

Abstract

Effect of supplemental manganese (Mn) on the growth of salt-stressed barley (Hordeum vulgare L.) was assessed to determine if a salinity-induced Mn deficiency was limiting plant growth. Sodium chloride (NaCl) was added to the black-cotton soil and salinity was maintained at 0.3, 4, 8, 12, and 16 dS m^?1. A negative relationship between percent seed germination and increasing salt concentration was obtained, however, results suggested that barley is salt tolerant at seed germination stage. Increasing concentration of NaCl significantly reduced plant growth. Also, salinity induced a Mn deficiency in shoots of plants. Manganese was added to the soil at control and at 8 dS m^?1 salinity. Supplemental Mn improved the growth of salt-stressed plants to a limited extent, but it did not improve the growth of control plants. Further, supplemental Mn increased the relative growth rate of salt-stressed plants and this increase was attributed to an increase in the net assimilation rate of salt-stressed plants and not to leaf area ratio. Salt concentration adversely affected the uptake of nitrogen and phosphorus by plants, which resulted in imbalance of nutrients in salt-stressed plants. It appears that factors other than Mn, such as ionic, water- and nutrient-stresses can limit the growth of salt-stressed plants and supplemental Mn has only a limited role in mitigation of adverse effect of salinity.     

Influence of Salt Stress on the Nutritional State of Cordyline fruticosa var. Red Edge: Chloride,Nitrogen, and Phosphorus

This trial was carried out to study the nutritional and productive behavior generated by modifications in the salt concentration in the nutrient solution for Cordyline fruticosa var. Red Edge plants. The anions studied were chloride (Cl), nitrogen (N), and phosphorus (P). Four treatments were tested: T₁ [control, 1.5 dS m^?1, 14.3 mmol L^?1 sodium chloride (NaCl)], T₂ (2.5 dS m^?1, 22.2 mmol L^?1 NaCl), T₃ (3.5 dS m^?1, 32.7 mmol L^?1 NaCl), and T₄ (4.5 dS m^?1, 38.2 mmol L^?1 NaCl). At the end of the cultivation, leaf, petiole, shoot and root fresh and dry weights, elemental extractions, and elemental concentrations were determined. Nutrient concentrations and total plant uptake (extraction) were calculated from the dry matter. The treatment T₂ induces a blade protection mechanism, which consists on the accumulation of chloride (Cl^?) in root and vessels; so, leaf storage is reduced, avoiding damages. Petiole also contributes to this protection, acting as a salt pool. As NaCl concentration in the nutritive solution arises, N plant concentration increases significantly although there are no significant differences between T₁ and T₂. With high salinity levels, P in vessels is reduced, whereas root extraction and concentration increases. The greatest N and P extractions are observed in T₂, which is due to its higher dry matter. Chloride extractions are lower in T₁ than in the other treatments.     

盐胁迫对番茄根形态和幼苗生长的影响

通过水培和培养基试验,研究了番茄幼苗生长和根构型在盐胁迫下的变化.结果表明,番茄幼苗地上部干、鲜重随着盐浓度增加而减小,根生物量受其影响相对较小;幼苗叶片叶绿素含量显著降低.50mmol/L NaCl显著抑制了侧根发育,侧根数显著降低,而100 mmol/L NaCl则显著抑制了主根和侧根伸长,由此可见,番茄根构型对盐胁迫响应比较敏感.     

Effect of Sodium Chloride Levels on Growth,Water Status,Uptake, Transport,and Accumulation Pattern of Sodium and Chloride Ions in Young Sunflower Plants

There is a paucity of information on the critical content, threshold levels, uptake, transport, and accumulation of sodium (Na⁺) and chloride (Cl^?) ions in young sunflower plants. Effect of salinity was analyzed in root, stem, leaves, and buds by raising plants in fine sand irrigated with Hoagland's solution and supplemented with 10–160 mM sodium chloride (NaCl) for 30 days. Maximum sensitivity index, reduction in growth, and water content were observed in buds. Maximum Na⁺ and Cl^? contents were obtained in old leaves and stems under low salinity but in roots at high salinity. Uptake, transport, and accumulation rate of Cl^? were more than those of Na⁺, and for both ions they increased with increasing NaCl concentration but decreased with increasing exposure time. Growth reduction at low salinity seems to be because of Cl^? toxicity, but Na⁺ toxicity and water deficiency could also be the causes at high salinity.     

Effect of Nitrogen Nutrition on Solute Accumulation and Ion Contents of Maize under Sodium Chloride Stress

Salinity is a major abiotic stress that limits the productivity of crops, particularly cereal crops, while decreasing nutrient availability, especially of nitrogen. An experiment was conducted to study the effects of salt stress [i.e., S₀, S₁, and S₂ (control, 1.09; 5; and 10 dS m^?1)] and four different nitrogen (N) levels [i.e., N₀, N₁, N₂, and N₃ (control, 175, 225, and 275 kg N ha^?1)] on two maize hybrids, Pioneer 32B33 (salt tolerant) and Dekalb 979 (salt sensitive). The experiment was conducted in a wire house. The experiment was laid out with three factors in a completely randomized design. The plant tissue was analyzed for solute and ion contents. With the increase in salt stress and N rate, solute (i.e., glycinebetaine), protein, total soluble sugar, and total free amino acids accumulated in both hybrids. Nitrate (NO₃) and nitrite (NO₂) reductase activity decreased sharply at 10 dS m^?1 compared to lower levels of salinity but it increased significantly with the addition of N. The uptake of potassium (K⁺), calcium (Ca²⁺), magnesium (Mg²⁺), N, and phosphorus (P) reduced significantly in shoots with increased salinity while the sodium (Na⁺) and chloride (Cl) contents were increased. It is concluded from the present study that at greater salinity level, hybrid Pioneer32B33 maintained statistically greater solute and ion contents excluding Na⁺ and Cl ions and significantly decreased enzyme activity. However, these parameters were increased by N rate.     

盐胁迫对银水牛果幼苗生长和生理特性的影响

通过盆栽试验,采用人为加入NaCl的方法以控制土壤含盐量(0.40%,0.60%,0.80%),研究盐胁迫对2年生银水牛果(Shepherdia argentea)幼苗叶片生长和生理特性的影响,结果表明:(1)随着土壤含盐量的增加,银水牛果幼苗的生长明显受到抑制,株高、生物积累量降低,单株总叶面积、叶片相对含水量减少,净光合速率下降;(2)随胁迫时间的延长,银水牛果幼苗叶片净光合速率在含盐量低于0.60%的土壤中先降低后升高,表明植物幼苗已适应了该盐分的土壤,银水牛果具有较强的耐盐性,本试验条件下以净光合速率下降50%为标准求得银水牛果的耐盐阈值为0.63%;(3)在相同含盐量的土壤中,与对照相比,Ca~(2+)的降幅小于K~+,表明银水牛果幼苗叶片以维持较高的Ca~(2+)含量,保证自身代谢的正常进行,通过提高Mg~(2+)含量以维持自身正常的光合作用,从而适应盐胁迫。     

Effects of Sodium Chloride Applications and Different Growth Media on Ionic Composition in Strawberry Plant

Abstract

The effects of salt (NaCl) applications of various concentrations (0, 500, 1000, and 2000 mg/L) for 10 weeks (69 days) on the morphologic properties and ionic composition of the “Camarosa” strawberry variety grown in perlite and perlite : zeolite (1:1) media were investigated. Injuries of varying severity appeared in the plants depending on the increase of NaCl concentration. At the end of the salt applications, in the aerial part of the plants, the amounts of sodium (Na), chlorine (Cl), calcium (Ca), and magnesium (Mg) had generally increased, while the amount of potassium (K) and phosphorus (P) had decreased. In the roots of the plants, salt applications increased the amount of Na and Cl and decreased the amount of K and Mg; however, they did not change the amount of Ca and P. In addition, in the aerial parts of the plant, the amounts of Ca and Mg were higher in the perlite : zeolite (1:1) medium than in the perlite medium generally. It was observed that in the roots, the amount of K was higher in the perlite medium, whereas the amount of Mg was higher in the perlite : zeolite (1:1) medium. It was determined that 500, 1000, and 2000 mg/L NaCl levels caused osmotic effects in the “Camarosa” strawberry variety. Moreover, they possess the ability to bring about osmotic regulation.     

硅对盐胁迫下黄瓜幼苗生长和矿质元素吸收的影响

采用幼苗水培实验,研究外源硅对盐胁迫下黄瓜幼苗生长过程中吸收某些矿质元素的影响。对植株地上部和地下部各元素的分析表明,盐胁迫条件下,外源硅有效调节了黄瓜根系对Na+、Ca2+、K+的吸收以及向地上部的转运。适量的硅降低了黄瓜根系从介质中吸收Na+量,并减少其向地上部的运输,而增加了植株体对K+、Ca2+的吸收和转运量,有效缓解了Na+对黄瓜植株体造成的盐胁迫伤害,保证了黄瓜幼苗的正常生长。在相同的处理条件下,盐分敏感品种的Na+在根系和地上部累积量都要比耐盐品种高,而K+的积累量却正好相反,这可能是耐盐品种减轻盐害的主要方式。对其它营养元素的研究表明,施硅抑制了对N素的吸收,对P素的吸收则影响不大。     

Silicon Effect on Nutrient Acquisition of Peanut (Arachis hypogaea L.) Under Aluminum Stress

Aluminum (Al) toxicity represents one of the main yield-limiting factors for crops in acid soils. Silicon (Si) is known to increase tolerance in higher plants. This study was conducted to determine whether treatment with Si could improve nutrient uptake by peanut under Al stress. Peanut (Arachis hypogaea L. cv Zhonghua 4) was raised with or without Si (1.5 mM) in the growth chamber under 0 and toxic Al (0.3 mM) levels. Aluminum stress significantly decreased the root- and total-dry weight by 52.4% and 32.0%, respectively. The content of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) was significantly decreased, but that of Al increased markedly in shoots and roots after Al exposure at seedling, flower-needle, and pod-setting stage. Silicon alleviates Al toxicity in peanut plants in relation to Al distribution and allocation of tissue P, K, Ca, and Mg by favoring the partitioning of dry mass to roots.     

Long-Term Influence of Nutrient Management on Carbon and Nutrients In Typic-Ustochrept Soils

ABSTRACT

Continuous incorporation of green manure (GM) and rice straw residue (RSR) over a long period of time generally improved soil physico-chemical properties. To generate this information, laboratory studies were conducted during 2014 on the soil samples collected from an on-going long-term experiment on rice–wheat sequence in progress since 2001. The results of the study reported improvement in bulk density, water holding capacity, and total porosity with green manuring. The maximum organic carbon build up was recorded in manure @ 15 t ha^?1 which was applied through GM. The application of fertilizers, GM and RSR incorporation improved the buildup of the available and total N, P, and K contents of surface soil. The data further indicated that the DTPA-extractable and total Zn, Cu, Fe, and Mn in soil increased significantly in all the fertilizer and manurial treatments over recommended practice. The integrated use of GM and RSR in combination with chemical fertilizers improved the soil fertility status, as well as its physical environment. To sustain the soil health of rice–wheat system in loamy sand soil, it is imperative to apply GM and RSR in combination with chemical fertilizers. Also the increase in DTPA-extractable and total Zn, Cu, Fe, and Mn may be attributed to chelating action of organic compounds released from manures applied in the form of GM and RSR under rice–wheat system.     

Effect of Enhanced Nickel Levels on Wheat Plant Growth and Physiology under Salt Stress

A pot experiment was conducted to study the response of wheat to concurrent stresses of salinity and nickel (Ni)-toxicity. Soil was spiked with Ni (0, 20 and 40 mg kg^?1) combined with two levels of salinity (control and 10 dS m^?1) using Ni(ii) nitrate hexahydrate (Ni(NO₃)₂.6H₂O) and sodium chloride (NaCl), respectively, in a completely randomized design with four replicates. Plants were harvested at the tailoring stage and the results showed that wheat growth was positively affected by Ni at 20 mg kg^?1, and negatively at 40 mg kg^?1 concentration both in control and at 10 dS m^?1. Ni (20 mg kg^?1) had a nonsignificant positive effect on tissue potassium (K⁺) and a significant negative effect on Na⁺ concentration. Moreover, Ni translocation from root to shoot and accumulation decreased by increasing the levels of Ni in both control and salinity treatments. It can be concluded that Ni at 20 mg kg^?1 increased wheat growth by alleviating salinity stress; however, at 40 mg kg^?1 it aggravated the plant stress and decreased the plant growth.