Levels Of NaCl Concentration Research Articles

Germination of Primed Seed under NaCl Stress in Wheat

Soil salinity affects a large and increasing amount of arable land worldwide, and genetic and agronomic solutions to increasing salt tolerance are urgently needed. Experiments were conducted to improve wheat seed performance under salinity stress conditions after priming. An experiment was conducted using a completely randomized design of four replications for germination indices in wheat (Triticum aestivumL. cv. Caxton). Normal and primed seed with PEG6000at MPa and five concentrations of NaCl (0, 50, 100, 150, and 200 mM) were tested. Results indicate that priming seed significantly () increased germination percentage at first count and final count, coefficient of velocity of germination, germination rate index, and mean germination time, while increasing of NaCl concentration significantly reduced it. Priming seed improved germination attributes at all NaCl concentration levels. The priming appeared to be able to overcome the effect of salt stress at 50 to 100 mM and reduce the effect of NaCl at higher concentrations up to 200 mM. The primed seed gave both faster germination and led to higher germination when under salt stress. We conclude that using priming techniques can effectively enhance the germination seed under saline condition.

Sodium Chloride Effects on Seed Germination, Growth and Ion Concentration in Chamomile (Matricaria Chamomilla)

Matricaria chamomilla is a medicinal plant that is widely cultivated in salt affected soils. This investigation was undertaken to study the effect of NaCl concentration on germination, and the physiological, biochemical and growth characteristics of chamomile. Seed germination and growth were studied at five NaCl concentration levels (0, 40, 80, 120 and 190 mM NaCl concentration). Increasing the level caused significant reduction in seed germination. Salt concentration up to 40 mM led to higher growth, but more than 40mM of NaCl caused significant growth limitation. Chloride and sodium ions increased significantly in various parts of the plant with salinity. Specifically, chloride ions were predominantly concentrated in the shoots whereas sodium ions were concentrated mostly in the roots. With increasing salinity rate, K and Ca concentration s significantly decreased in the shoot and root of M. chamomilla as compared to the control. There was a consistent decrease in K + /Na + and Ca 2+ /Na + ratios in the shoots and roots of M. chamomilla. Plants maintained considerably higher K + /Na + and Ca 2+ /Na + ratios in the shoots than the roots, and the former ratio was significantly higher than 1 in a 40mM salinity level. No change in leaf proline concentration was observed up to 80 mM, but a sharp rise at higher salt levels occurred. Overall, based on the results, M. Chamomilla is a tolerant to moderately salt tolerant crop during its growth, and its response to salinity is associated with the maintenance of high K + /Na + and Ca 2+ /Na + ratios in shoots, the accumulation of Na + in roots, and

Role of salt stress on seed germination and growth of jojoba plant Simmondsia chinensis (Link) Schneider

An extensive problem in agriculture is the accumulation of salts from irrigation water. Evaporation and transpiration remove pure water from the soil. This water loss concentrates solutes in the soil. When irrigation water contains a high concentration of solutes, salts can reach rapidly injurious levels vis-a-vis salt-sensitive species. One factor limiting jojoba plant ( Simmondsia chinensis (Link) Schneider) domestication in the oriental areas of Morocco is the damage caused by salt effect since irrigation enhances salinity in plantation soils. The objectives of this study were to define the effect of various NaCl concentration levels on plant growth and seed germination. The tolerance to salinity of jojoba seed and seedlings was assessed at NaCl concentrations of 0, 1, 2, 3, 5, and 7 g l −1 and the experiment was undertaken in the laboratory under greenhouse conditions. Results obtained show that more than half of the seeds germinated in the presence of 7g/l of NaCl; whereas 5g/l of NaCl inhibited completely the emergence of plumules. Concerning jojoba seedlings, 3 g/l of NaCl marked the start of negative affect on the growth.

Prediction of the partitioning behaviour of proteins in aqueous two-phase systems using only their amino acid composition

The prediction of the partition behaviour of proteins in aqueous two-phase systems (ATPS) using mathematical models based on their amino acid composition was investigated. The predictive models are based on the average surface hydrophobicity (ASH). The ASH was estimated by means of models that use the three-dimensional structure of proteins and by models that use only the amino acid composition of proteins. These models were evaluated for a set of 11 proteins with known experimental partition coefficient in four-phase systems: polyethylene glycol (PEG) 4000/phospate, sulfate, citrate and dextran and considering three levels of NaCl concentration (0.0% w/w, 0.6% w/w and 8.8% w/w). The results indicate that such prediction is feasible even though the quality of the prediction depends strongly on the ATPS and its operational conditions such as the NaCl concentration. The ATPS 0 model which use the three-dimensional structure obtains similar results to those given by previous models based on variables measured in the laboratory. In addition it maintains the main characteristics of the hydrophobic resolution and intrinsic hydrophobicity reported before. Three mathematical models, ATPS I–III, based only on the amino acid composition were evaluated. The best results were obtained by the ATPS I model which assumes that all of the amino acids are completely exposed. The performance of the ATPS I model follows the behaviour reported previously, i.e. its correlation coefficients improve as the NaCl concentration increases in the system and, therefore, the effect of the protein hydrophobicity prevails over other effects such as charge or size. Its best predictive performance was obtained for the PEG/dextran system at high NaCl concentration. An increase in the predictive capacity of at least 54.4% with respect to the models which use the three-dimensional structure of the protein was obtained for that system. In addition, the ATPS I model exhibits high correlation coefficients in that system being higher than 0.88 on average. The ATPS I model exhibited correlation coefficients higher than 0.67 for the rest of the ATPS at high NaCl concentration. Finally, we tested our best model, the ATPS I model, on the prediction of the partition coefficient of the protein invertase. We found that the predictive capacities of the ATPS I model are better in PEG/dextran systems, where the relative error of the prediction with respect to the experimental value is 15.6%.

Ultrasound-Induced Aqueous Removal of Nitric Oxide from Flue Gases: Effects of Sulfur Dioxide, Chloride, and Chemical Oxidant

The effects of sulfur dioxide (SO(2)), sodium chloride (NaCl), and peroxymonosulfate or oxone (2KHSO(5).KHSO(4).K(2)SO(4) with active ingredient, HSO(5)(-)) on the sonochemical removal of nitric oxide (NO) have been studied in a bubble column reactor. The initial concentration of NO studied ranged from about 500 to 1040 ppm. NaCl in the concentration range of 0.01-0.5 M was used as the electrolyte to study the effect of ionic strength. At the low NaCl concentration (0.01 M), the percent fractional removal of NO with initial concentration of 1040 ppm was enhanced significantly, while as the NaCl concentration increased, the positive effects were less pronounced. The presence of approximately 2520 ppm SO(2) in combination with 0.01 M NaCl further enhanced NO removal. However, with a NO initial concentration of 490 ppm, the addition of NaCl was detrimental to NO removal at all NaCl concentration levels. The combinative effect of sonication and chemical oxidation using 0.005-0.05 M oxone was also studied. While the lower concentrations of HSO(5)(-) enhanced NO removal efficiency, higher concentrations were detrimental depending on the initial concentration of NO. It was also demonstrated that in the presence of ultrasound, the smallest concentration of oxone was needed to obtain optimal fractional conversion of NO.

Sorghum and Salinity

Photosynthetic activity decreases when plants are grown under saline conditions leading to reduced growth and productivity. Leaf growth, gas exchange, and chlorophyll fluorescence of two sorghum [Sorghum bicolor (L.) Moench] varieties, Serena and Seredo, were measured in response to increasing NaCl concentration. Sorghum plants were grown in sand culture under controlled greenhouse conditions. The NaCl concentrations in complete nutrient solution were 0 (control), 50, 100, 150, 200, and 250 mM Salinity significantly (P ≤ 0.01) reduced leaf area by about 86% for both varieties of sorghum. Chlorophyll a and b, net CO2 assimilation, stomatal conductance, and transpiration rate decreased significantly (P ≤ 0.01) with the increase in salinity, and these decreases were similar for the two sorghum varieties. Salt induced decreases for these physiological traits ranged from 75 to 94%. Photochemical efficiency of PSII (Fv/Fm) and photochemical quenching coefficient (qP) decreased by about 9 and 10%, respectively, for both varieties, and electron transport rate (ETR) decreased by 20 and 25% for Serena and Seredo. In contrast, non‐photochemical quenching (NPQ) significantly (P ≤ 0.01) increased by 44 and 50% for Serena and Seredo. The results indicate that salinity affected photosynthesis per unit leaf area indirectly through stomatal closure, and to a smaller extent through direct interference with the photosynthetic apparatus. In addition, salinity decreases whole plant photosynthesis by restricting leaf area expansion. This effect starts from low levels of salinity, in contrast to that of net photosynthesis per unit leaf area, which occurs at higher levels of NaCl concentration.

Growth kinetics of Vibrio parahaemolyticus O3:K6 under varying conditions of pH, NaCl concentration and temperature.

The growth responses of Vibrio parahamolyticus to pH, NaCl concentration and temperature changes were studied using serotype O3:K6 and other strains. Growth curves were obtained for 27 different sets of conditions, comprised of three levels of NaCl concentration, pH and temperature. The temperature, pH and NaCl concentrations most favorable for growth were in the order of 25 degrees C, 20 degrees C and 15 degrees C, pH 8, 7 and 5.8, and 1%, 3% and 7%, respectively. The bacteria grew most rapidly at 25 degrees C, at a pH of 7 or 8 in the presence of 1% or 3% NaCl, with the population (initial, ca. 2.5 log CFU/mL) reaching a level log 7 CFU/mL at 12 h. A growth predictive model using the Gompertz equation was generated from the experimental data for any combination of NaCl concentration, pH and temperature within the range used in this study.

Oxidation of diazinon by anodic Fenton treatment

Anodic Fenton treatment (AFT) is a new technology that has several advantages over classic Fenton treatment and electrochemical Fenton treatment. The oxidation of diazinon by AFT using different electrolytes has been investigated. NaCl, KCl and Na 2SO 4 show similar effects on the extent and rate of oxidation, and the data can be fitted quite well by the AFT kinetics model. Use of NaNO 3 as the electrolyte causes low-efficiency electrolysis and a subsequent low oxidation rate for diazinon. The NaCl concentration level in the anodic half-cell and the concentration ratio between the two half-cells is optimized at 0.04 M and 4:1 (cathodic/anodic), respectively. The activation energy of diazinon oxidation by anodic Fenton treatment is estimated to be 12.6±0.6 kJ mol −1, which is less than half of that for aqueous chlorine treatment. Diazoxon is the intermediary oxidation product. The oxidation of diazinon as a formulated product has also been investigated. Its dissipation kinetics can also be fitted quite well by the AFT model. Compared with the oxidation of pure diazinon, the oxidation rate of formulated diazinon is much lower, an indication that many formulation ingredients compete with diazinon for reaction with the hydroxyl radical.

CRESCIMENTO E RELAÇÕES HÍDRICAS EM PLANTAS DE GOIABEIRA SUBMETIDAS A ESTRESSE SALINO COM NaCl

Tendo como objetivo determinar os efeitos do estresse salino sobre o crescimento e as relações hídricas de plantas de goiabeira (Psidium guajava L), conduziu-se um experimento em casa de vegetação, em solução nutritiva, na Universidade Federal do Ceará, no período de setembro a dezembro de 1997. Os tratamentos consistiram de sete níveis de NaCl (0; 25; 50; 75; 100; 125 e 150 mmol L-1). Avaliaram-se, aos 50 dias após o estresse salino (DAE): altura da planta, número de folhas e área foliar unitária e por planta. A taxa de crescimento relativo (TCR) foi determinada entre 30 e 50 DAE. Aos 20; 30; 40 e 50 DAE, foram determinadas condutâncias estomáticas, transpiração, potencial hídrico e teor relativo de água (TRA). Dentre as variáveis estudadas, a área foliar por planta foi a mais afetada, com uma redução de 92% quando submetida ao nível mais elevado de salinidade (150 mmol L-1). A condutância estomática, a transpiração, o potencial hídrico foliar (psiwf) e o teor relativo de água (TRA) decresceram com o aumento dos níveis e do tempo de exposição ao NaCl. As plantas jovens de goiabeira são sensíveis à salinidade, com uma salinidade limiar de 1,2 dSm-1. A taxa de sobrevivência foi reduzida em 75% quando as plantas foram submetidas a 150 mmol L-1 até 50 dias após o estresse.

Influence of pH and sodium chloride on selected functional and physical properties of African breadfruit (Treculia africana Decne) kernel flour.

African breadfruit seeds were cleaned, parboiled (98 degrees C) for 15 min, drained and dehulled. The kernels were sun-dried, then milled and sieved into flour. Nitrogen solubility (NS), water absorption capacity (WAC), emulsion activity (EA), viscosity, foaming and emulsifying properties of the flour were determined as functions of pH and NaCl concentration. The NS was pH dependent with a minimum at pH 4 and maximum at pH 10. The flour also exhibited minimum and maximum foam capacity at pH 4 and 10, respectively. The minimum emulsion activity was at pH 4, a value which increased from 7-16% at pH 12. The addition of NaCl at concentrations of 0.2 to 0.4 M improved WAC, NS, foaming and emulsion properties of the flour. Sodium chloride enhanced NS of the flour at pH 4-6 and EA at pH 2-8. The EA at pH 2, 10 and 12 correlated negatively (r = -0.30) with NaCl concentration levels; however, the correlation was not significant (p > 0.05). The flour dispersions had lower viscosities at acid pH and in the presence of NaCl than at neutral and alkaline pH values. Results indicated the flour could be used in food product supplementation.

Distribuição da matéria seca e composição química das raízes, caule e folhas de goiabeira submetida a estresse salino

Um experimento em casa de vegetação foi conduzido com o objetivo de estudar a resposta de plantas de goiabeira (Psidium guajavaL.) a diferentes concentrações de NaCl. As plantas foram cultivadas em solução nutritiva, com 0, 25, 50, 75, 100, 125 e 150 mM de NaCl, e colhidas com 30 e 50 dias após estresse, num delineamento inteiramente casualizado. Foram determinadas: matéria seca das raízes e parte aérea; e porcentagens de Na, Cl, K, Ca e Mg nas raízes, caule e folhas. O estresse salino reduziu a matéria seca total, e a relação parte aérea/raiz foi reduzida. O estresse causou um aumento nos níveis dos íons Na+ e Cl-, com maior acúmulo nas folhas, seguido das raízes. Os teores de Ca foram estáveis nas raízes, mas decresceram no caule e folhas. Os teores de K foram reduzidos, particularmente nas folhas. Ao contrário, os teores de Mg não foram afetados pela salinidade no caule e nas raízes, havendo, entretanto, redução nas folhas. O teor de Na apresentou relação direta com o de Cl e inversa com o de K nas raízes e folhas. O teor de Ca não variou com o de Na nas folhas, mas apresentou uma relação inversa nas raízes. O teor de Mg não variou com o de Na nas raízes e folhas.

Effect of soil type, salinity, and allelochemicals on germination and seedling growth of a medicinal plant Lepidium sativum L.

SummaryThe present work was conducted to elucidate the effect of soil type, salinity stress and allelochemicals from alfalfa on the germination efficiency, seedling growth and photosynthetic pigments of Medicago sativa L. The highest germination rate (69.9%) was recorded for seeds cultivated in sandy soil followed by that of clay soil (42%) and then loamy soil (19%).The maximum germination rate was attained at 50 mM NaCl concentration level, after that the values were decreased as the salinity levels increased. The maximum lengths (cm) of plumule and radicle and their growth rates (cm/day) were obtained at control level and found to decline significantly as the salinity increased.Aqueous extracts of alfalfa reduced the germination rate, radicle and plumule growth and seedling dry weight of L. sativum. However, chlorophyll and carotenoid content was increased, their maxima were recorded at 50% concentration level. The chlorophyll a/b ratio attained its maximum at the full strength concentration level.

A new isolate of Hydrogenobacter, an obligately chemolithoautotrophic, thermophilic, halophilic and aerobic hydrogen-oxidizing bacterium from seaside saline hot spring

An obligately chemolithoautotrophic and aerobic hydrogen-oxidizing bacterium was isolated from a seaside saline hot spring in Izu Peninsula, Japan. The isolate was a Gram-negative, non-motile, non-spore-forming rod cell measuring 0.3 to 0.5 by 1.0 to 2.5 μm. The optimal temperature for growth was around 70°C, and no growth was observed at 40°C or 80°C. Elemental sulfur or thiosulfate could be an alternative to molecular hydrogen as the sole energy source. The DNA base composition of the isolate was 46.0 mol% G+C. 2-Methylthio-3-VI,VII-tetrahydromultiprenyl7-1,4-naphthoquinone (methionaquinone) was the major component of the quinone system. C18:0, C18:1 and C20:1 were the major components of the cellular fatty acids. These properties clearly indicate that the isolate belongs to genus Hydrogenobacter, but differed from H. thermophilus in some respects. Specifically, the isolate was a halophile which grew optimally at around 0.3–0.5 M NaCl, while H. thermophilus could not grow at such NaCl concentration levels. A new species name H. halophilus is proposed for this new halophilic isolate.

Minerals in plasma and urine and gustatory function tests for salt in a group of healthy young men.

Detection threshold for salt (NaCl) and discrimination between two levels of NaCl concentration (0.6 and 0.7%) in foods, and their relation to some selected biochemical parameters in plasma and urine (Zn, Na, K, Mg, Ca, Se for plasma and urine, Cu and retinol binding protein for plasma) were investigated in 15 healthy male college students. No subject failed to discriminate the NaCl concentrations in more than 50% of the tests. The rate of correct discrimination (RCD) was not associated with plasma Zn (P-Zn), plasma retinol binding protein (P-RBP), urinary potassium (U-K) or urinary sodium (U-Na), which significantly correlated with RCD in our previous study, while the detection threshold was significantly correlated with urinary Ca-Mg ratio (U-Ca/Mg), urinary Ca (U-Ca), U-Na, and urinary Mg. In the stepwise multiple regression analysis, U-Ca/Mg, plasma Ca, plasma Na, and RCD were selected as significant independent variables. These indicate that the status of minerals such as Na, Ca, and Mg is related to the gustatory function. One possible explanation for the discrepancy between the present and previous results is the elevated P-Zn and P-RBP levels in the present subjects.

Skin conductance recordings and the NaCl concentration of the electrolyte.

ABSTRACTThis study examined the effects of four levels of NaCl concentration (0.1–0.7%) on skin conductance responses (SCRs) and levels (SCLs) to deep breaths and loud noise. Twenty‐four subjects of both sexes took part in two identical experimental sessions, 7 days apart. All subjects encountered all four electrolyte concentrations. The results showed no effects of electrolyte concentration on SCLs or on the SCRs to the deep breaths, but indicated larger SCRs to the loud noise with the highest NaCl concentration.

Salt tolerance of Rhizobium species in broth cultures

Salt tolerance of five rhizobia strains was examined in broth cultures. Five levels of NaCl concentration were used and the optical density was taken as a measure for the vigour of bacterial growth. Rhizobium leguminosarum and R. meliloti were tolerant to high levels of salinity and growth curves in saline broth showed a similar pattern to the control level. Rhizobium japonicum, cowpea Rhizobium, and R. trifolii were intolerant to salt and showed a strong growth retardation with increasing salt concentration. Growth was inhibited at high levels of salinity. It is suggested that rhizobia sensitivity to salts may be partly responsible to the inhibition of nitrogen fixation by legumes growing under salt stress.

Identification of salt tolerant barley genotypes for coastal region of Bangladesh

Identification of salt tolerant barley (Hordeum vulgare L.) genotypes and effects of different levels of salinity on their growth, grain development and yield were studied. One hundred and eighty nine barley germplasms were subjected in five levels of NaCl concentration which were equivalent to Electrical Conductivity (EC) of 0, 10, 15, 20 and 25 ds/m. Among the genotypes 39 proved to be saline tolerant at 15 ds/m of salinity. Out of 39 genotypes, 33 were evaluated at Sonagazi and Patuakhali salt area of Bangladesh. All the genotypes were evaluated in the non-saline area at BARI, Gazipur to observe their performance in normal soil. Highest grain yield was recorded from the genotypes BSH-32 and BSH-142 over the three locations. Significantly higher yield was recorded from the experimental site of Gazipur followed by Patuakhali and Sonagazi. Tiller per plant had positive correlation with grain per spike, maturity and grain yield. Grain per spike and maturity was positively correlated with grain yield. From the multivariate analysis it appears that 1st, 2nd and 3rd principal components together account for 79 per cent of the total experimental variation. The two selected genotypes are expected to be released for commercial cultivation in the saline area of Bangladesh. Â Â Â Â Â Key words: Barley, Genotypes, Selection, Salt tolerant, Bangladesh DOI = 10.3329/bjb.v36i2.1504 Bangladesh J. Bot. 36(2): 151-155, 2007 (December)