Application Of KCl Research Articles

Dissociated Hippocampal Neurons Exhibit Distinct Zn2+ Dynamics in a Stimulation-Method-Dependent Manner.

Ionic Zn2+ has increasingly been recognized as an important neurotransmitter and signaling ion in glutamatergic neuron pathways. Intracellular Zn2+ transiently increases as a result of neuronal excitation, and this Zn2+ signal is essential for neuron plasticity, but the source and regulation of the signal is still unclear. In this study, we rigorously quantified Zn2+, Ca2+, and pH dynamics in dissociated mouse hippocampal neurons stimulated with bath application of high KCl or glutamate. While both stimulation methods yielded Zn2+ signals, Ca2+ influx, and acidification, glutamate stimulation induced more sustained high intracellular Ca2+ and a larger increase in intracellular Zn2+. However, the stimulation-induced pH change was similar between conditions, indicating that a different cellular change is responsible for the stimulation-dependent difference in Zn2+ signal. This work provides the first robust quantification of Zn2+ dynamics in neurons using different methods of stimulation.

Growth Characteristics and Fruit Quality of Chili Pepper under Higher Electrical Conductivity of Nutrient Solution Induced by Various Salts

Salinity as a global challenge is a very complex issue in agricultural food production. In this study, the growth characteristics of chili pepper (Capsicum annuum var. crusader) were evaluated under higher Electrical Conductivity (EC) (5 dS/m) induced by NaCl, KCl, K₂SO₄ or “All Nutrients” of Hoagland nutrient solution. The standard Hoagland solution (with EC 1.8 dS/m) was used as the control. The results showed that EC5 induced by NaCl resulted in the most negative effects on growth, yield and fruit quality parameters. Application of KCl (to induce EC5) also resulted in some reduction in growth parameters. However, application of K₂SO₄ and particularly “All Nutrients” (to induce EC5) resulted in better growth characteristics compared to plants treated with NaCl or KCl salts. There was a significant reduction in growth and fruit quality traits including plant height, leaf SPAD value, fresh and dry weights of shoots and roots, fruit fresh yield, fruit total soluble solids (TSS) and vitamin C content by NaCl and to lesser extent by KCl. However, there was no significant reduction in these traits by “All Nutrients” and for some traits by K₂SO₄ application compared to control plants.

Nitrogen and potassium fertilization in no‐till hard red spring wheat production

AbstractThere is a need to develop more efficient nutrient management strategies to maximize wheat (Triticum aestivum L.) grain yields and increase grain protein levels. Urea, most widely used N fertilizer, is susceptible to substantial losses, resulting in low nitrogen use efficiency (NUE). This study assessed the effect of N and K fertilization on hard red spring wheat production under dryland no‐till conditions in Montana. A field experiment was conducted during one growing season at two locations in Northcentral Montana. Fertilizer N was applied as urea (46–0–0) or as a urea–KCl (50:50 blend) at planting to achieve two target N rates, 135 and 270 kg N ha−1. Biomass weight, N content, and sensor‐based Normalized Vegetative Difference Index (NDVI), yield, test weight, and grain protein content of wheat was evaluated. Results indicated that: (a) N may increase wheat grain quality (protein content) even when wheat yield is not increased, (b) KCl application, along with N, may result in greater wheat biomass production and grain protein values, and (c) NDVI may be more sensitive to the amount of produced biomass than to N content of that biomass. In conclusion, even if yield response to N is minimal, N is beneficial for improving grain protein content of wheat. Addition of KCl along with N may produce greater wheat biomass and increase biomass N content. The NDVI may be more sensitive to the amount of produced biomass than to its N content.

NUTRIENT UPTAKE, PROLINE CONTENT AND ANTIOXIDANT ENZYMES ACTIVITY OF PEPPER (Capsicum annuum L.) UNDER HIGHER ELECTRICAL CONDUCTIVITY OF NUTRIENT SOLUTION CREATED BY NITRATE OR CHLORIDE SALTS OF POTASSIUM AND CALCIUM

This study was conducted to evaluate effects of higher conductivity of nutrient solution created by nitrate or chloride salts of potassium and calcium on growth characteristics of pepper plants (Capsicum annuum var annuum) during four months of growth period. Two EC5 and EC8 dS/m of Hoagland nutrient solution were prepared using various salt combinations, namely; KCl + CaCl2, KNO3 + CaNO3, and KNO3 + CaNO3 + NaCl. Hoagland nutrient solution with EC 1.8 dS/m was served as control. Higher conductivity treatments had different effects on pepper plant growth. The most significant reduction in growth parameters of plant height, shoot fresh weight, fruit yield and nutrients uptake were in plants treated with KCl + CaCl2 particularly at EC8. Application of KNO3 + CaNO3 particularly at EC5 showed no difference with control regarding many growth parameters. Application of KNO3 + CaNO3 at EC5 resulted in higher shoot fresh weight compared to control. All salinity treatments except KNO3 + CaNO3 at EC5 reduced fruit yield compared to control. Treatments of KCl + CaCl2 and KNO3 + CaNO3 + NaCl particularly at EC8 of nutrient solution resulted in higher leaf proline concentration, catalase and peroxidase enzymes activity compared to control. Other conductivity treatments showed no difference in catalase or peroxidase enzymes activity. The significant lowest amount of leaf N, K, Mg and Ca was in KCl + CaCl2 at EC8. On the other hand, the highest leaf macronutrient concentrations were in KNO3 + CaNO3 at EC5 and/or EC8 that showed only higher leaf N and Ca values compared to control. Leaf micronutrient concentrations were highest in KNO3 + CaNO3 at EC5 that generally showed no difference with control plants. However, application of KCl + CaCl2 particularly at EC8 and to less extent KNO3 + CaNO3 + NaCl at EC8 reduced leaf micronutrient concentrations. Application of KNO3 + CaNO3 at EC5 increased and KCl + CaCl2 or KNO3 + CaNO3 + NaCl at EC8 decreased the leaf Fe concentration compared to control plants.

Planting Densities and Forms of Potassium Fertilization in the Development of Edamame (Glycine max (L.) Merril) Cultivation

The edamame is the soybean harvested in the R6 phenological period when the seed in green. That is the reason of its name, Green Soybean. To evaluate the influence of different planting densities and two types of potassium fertilizer on the agronomic components of the edamame cultivar BR 9452273, an experiment was conducted in the municipality of Boa Vista-RR between early 2015 and March 2016. The experimental design was a complete randomized block design in a 4 × 2 factorial scheme with four plant densities (140, 160, 200 and 240 thousand plants ha-1) and two forms of potassium fertilization in the last split-application (potassium chloride-KCl (control) and a Leaf fertilizer-K-20) on the same concentration (30 kg ha-1) for both treatments, with three replicates. Plant cultivation variables were evaluated, as well aspod productivity and the reproductive and maturation periods of the plants. Based on the results obtained, the BR-9452273 edamame lineage showed early growth and maturation under local edaphoclimatic conditions, with reproductive and maturation periods of 24 and 73 days after planting, respectively. Plant height and the insertion of the first pod, the diameter of the stem, and pod number in a sample of 500 g were affected by the joint action of the evaluated factors. Green pod yield and total biomass were favored by both higher and lower density, which alongside the application of KCl, were the most effective treatments for production of edamame in the Cerrado of Roraima.

Amelioration of drought stress in black matpe bean (Vigna mungo L.) by foliar application of potassiu

Growth, physiological and biochemical activities of black matpe bean grown in pot cultures were evaluated to recognize the ameliorative role of potassium against the deleterious effects of water deficit. Black matpe plants were subjected to four levels of water stress (400 ml, 200 ml, 100 ml and 50 ml). The control plants were supplied with 500 ml of water at regular intervals. Potassium was applied in form of 200 ppm KCl and KNO3. Plants were under observation starting from 25 upto 55 days of plant growth at 10-day interval for each treatment. Water deficit stress reduced biomass, leaf area and RWC and provoked oxidative stress in plants as confirmed by considerable increase in electrolyte leakage, proline and reducing sugar content. Foliar application of KCl and KNO3 improved all these attributes under water stress. The ameliorative effect might be maintained through decrease in proline and increase in reducing sugar content. Increased reducing sugar content in K treated plants may have a significant role in osmotic adjustment.

Effects of NaCl on Growth and Cesium Absorption in Quinoa (Chenopodium quinoa Willd.)

In this study, we clarified the effects of NaCl application on the growth and Cs absorption in quinoa (Chenopodium quinoa Willd.). Pot experiments using Wagner pots (1/5000a) were conducted in an experimental field at Nihon University during 2014, 2015, and 2016, using quinoa variety CICA-127. Growth of quinoa and Cs absorption by quinoa were promoted by the application of NaCl. The Cs content of aboveground parts of plants was also increased by the application of NaCl; however, the differences in Cs content among plots were not significant. Thus, the reason for the increase in Cs absorption was the promotion of biomass by the application of NaCl. The exchangeable K content in the soil and the growth of quinoa were increased by the application of KCl. Therefore, increasing the exchangeable K content in soil by the application of KCl has contributed to the increased accumulation of K and the decreased accumulation of Cs in the aboveground parts of plants. Thus, the lower exchangeable K content in soil led to a lower plant K content and a greater absorption of Cs by quinoa.

Near infrared imaging of intrinsic signals in cortical spreading depression observed through the intact scalp in hairless mice

Brain cooling was inevitable in both thinned and intact skull windows in neuroimaging in vivo of mice. Thus we proposed the novel imaging method leaving intact scalp on the skull using the light at 670, 785, and 975 nm. In this study, we used hairless mice (Hos:HR-1) since the deterioration of image quality was resulted from the hair. Cortical spreading depression was induced by KCl application through small incision and burr hole on the frontal bone. Intrinsic optical signals through the intact scalp in the observation area were detected. Time course of the signal showed a triphasic feature which was consistent with the intrinsic optical signals through the intact skull. In three pairs of signal amplitudes at the different wavelengths, no significant differences were observed. Although the intact scalp weakened the amplitudes significantly, e.g., 4.0 from 6.9 at 975 nm, the signals during cortical spreading depression were sufficient to be detected.

The Effect of Neuronal Activity on Glial Thrombin Generation.

Thrombin through its receptor PAR-1 plays an important role in the peripheral nervous system. PAR-1 is located at the microvilli of Schwann cells at the node of Ranvier, and thrombin is generated by the coagulation system on these glial structures. In the present study, we examined the link between neuronal activity and modulation of thrombin generation by glial Schwann cells. Thrombin activity was assessed in sciatic nerves in reaction to high KCl as a model of neuronal activity. We demonstrated a significant transient effect of high KCL on thrombin activity (F(5, 20) = 42.65, p < 0.0001, by ANOVA) compared to normal KCl levels. Since the sciatic nerve includes components of axons and Schwann cell myelin sheath, we continued to investigate the effect of high KCl on a Schwannoma cell line as a model for nodal Schwann cell microvilli. We demonstrated a transient decrease in thrombin activity in response to high extracellular KCl (F(1, 18) = 9.56, p = 0.0063). The major neuronal inhibitor of thrombin is PN-1, and we therefore measured the effect of high KCL on PN-1 immunofluorescence intensity. We found significantly higher PN-1 staining intensity 3min after the application of high KCL in comparison to cells exposed to high KCL for 7min and to cells in regular KCL (F(2, 102) = 8.4737, p < 0.0004), and this effect may explain the changes in thrombin activity. The present results support an interaction between neuronal activity and the coagulation pathway as a novel mechanism for neuron-glia crosstalk at the node of Ranvier.

Potassium chloride: impacts on soil microbial activity and nitrogen mineralization

ABSTRACT: Potassium chloride is the most widely used potassium source worldwide, and due to its continuous use, the accumulation of its salts in the soil and in plants is becoming more common. Excess available ions can cause a series of physiological disturbances in organisms and can become a biocide in the soil. The objective of this study was to evaluate the effects of the application of KCl and banana crop residues on soil chloride content, microbial activity, and soil ammonification. The experiment utilized a completely randomized 2 × 4 factorial design with four replicates. Treatments were as follows: two doses of vegetal residue (200 and 400 mg dm-3) × four doses of KCl (0, 167, 334, and 668 mg dm-3 of KCl) and a control (untreated soil). The CO2 emission, ammonium (N-NH4 +) and soil chloride (Cl-) content, and mineralization/immobilization rates of the soils in each treatment were measured 4, 45, and 130 days after incubation (dai). Higher KCl dosages reduced soil microbial activity at 4 dai, regardless of the residue dosage. Microbial activity was reduced at 130 dai in all treatments when compared to the initial period. Higher dosages of banana crop residues increased the Cl- content of the soil and promoted the immobilization of N-NH4 +. We concluded that dosages of KCl (above 400 mg dm-3), when applied to soils that already contain crop residues, reduce microbial activity and mineralization of N in the soil.

Alternative sources of potassium for maize cultivation

ABSTRACT Brazil is the largest importer of potassium (K) fertilizers in the world, importing about 95% of all the potassium consumed by its agriculture. Thus, new sources and technologies to increase K availability have been studied. This study aimed to evaluate the agronomic viability of the use of calcined glauconite and phonolite blended and granulated with two organic materials on maize growth in pots, using two soils of contrasting texture in a controlled environment. Were evaluated eight sources of potassium: phonolite; phonolite + poultry manure; phonolite + cattle manure; calcined glauconite; calcined glauconite + poultry manure; calcined glauconite + cattle manure; negative control (no K); and positive control (K - KCl), and two soils of contrasting texture. The experiment was carried out for 38 d. The following parameters were analyzed: plant height, stem diameter, shoot dry mass, leaf number, leaf contents of nitrogen (N), K and phosphorus (P), and the SPAD chlorophyll meter. In the sandy soil, the source consisting of phonolite + chicken manure was similar to KCl application regarding plant height, stem diameter and shoot dry mass. As for the clayey soil, when both rocks were blended with the organic wastes, they were similar to KCl for shoot dry mass. The use of pure granulated rocks, calcined glauconite and phonolite without blending with the organic residues is not efficient to provide available K to maize plants.

Short-term activation of synaptic transmission by acute KCl application significantly reduces somatic A-type K+ current.

Short-term activation of synaptic transmission by acute KCl application significantly reduces somatic A-type K+ current.

Increased susceptibility to cortical spreading depression and epileptiform activity in a mouse model for FHM2

Migraine is a highly prevalent, debilitating, episodic headache disorder affecting roughly 15% of the population. Familial hemiplegic migraine type 2 (FHM2) is a rare subtype of migraine caused by mutations in the ATP1A2 gene, encoding the α2 isoform of the Na+/K+-ATPase, predominantly expressed in astrocytes. Differential comorbidities such as epilepsy and psychiatric disorders manifest in patients. Using a mouse model harboring the G301R disease-mutation in the α2 isoform, we set to unravel whether α2+/G301R mice show an increased susceptibility for epilepsy and cortical spreading depression (CSD). We performed in vivo experiments involving cortical application of KCl in awake head-restrained male and female mice of different age groups (adult and aged). Interestingly, α2+/G301R mice indeed showed an increased susceptibility to both CSD and epileptiform activity, closely replicating symptoms in FHM2 patients harboring the G301R and other FHM2-causing mutations. Additionally, this epileptiform activity was superimposed on CSDs. The age-related alteration towards CSD indicates the influence of female sex hormones on migraine pathophysiology. Therefore, the FHM2, α2+/G301R mouse model can be utilized to broaden our understanding of generalized epilepsy and comorbidity hereof in migraine, and may be utilized toward future selection of possible treatment options for migraine.

English

English

Application of polyether amine, poly alcohol or KCl to maintain the stability of shales containing Na-smectite and Ca-smectite

ABSTRACTThe stability of a shale containing smectite with different exchangeable cations (Na+, Ca2+) was improved using optimum solutions containing polyether amine (PA), poly-alcohol (PO) or KCl. Two types of shale samples with Na+ and Ca2+ as the main exchangeable cations, respectively, were used and the optimized solutions were determined using X-ray diffraction (XRD), an adsorption test, an oedometer swelling test, and an immersion test. The use of KCl prevented intercalation of PA or PO and maintained the stability of the Na-smectite-bearing shale. PA or PO adsorption reduced water adsorption sites on the clay layer, and K+ reduced hydration of exchangeable Na+, resulting in good shale stability in mixed solutions of KCl+PA, and KCl+PO. More stable shale was achieved in KCl+ PA mixed solution, whereas in the KCl+ PO solution the transport of water or solute molecules in the shale was reduced. In the shale containing mainly Ca-smectite, PA, PO and KCl maintained shale stability when applied separately or in common, as PA or PO cannot exchange Ca2+ in the smectite interlayer. As a result, PA or PO should be used together with KCl during drilling in shale formations containing Na-smectite, whereas in shales with Ca-smectite, PA, PO or KCl may be used separately.

Phosphorus and potassium availability from cattle manure ash in relation to their extractability and grass tetany hazard

ABSTRACTDue to a decrease in phosphorus (P) and potassium (K) mining, manure is incinerated to concentrate P and K in ash. To understand the alternative use of manure-derived ash as P and K sources, laboratory and greenhouse experiments were conducted to determine the relationship between extractability and P and K uptake in cattle manure ash (CMA) and that between CMA application and a grass tetany hazard. The results showed that more P was extracted with 2% citric acid (90% of the total P) than with 2% formic acid (72–84% of the total P). Ninety-one percent of the total K was soluble in water. A greenhouse pot experiment was conducted to test P and K availability to Guinea grass (Megathyrsus maximus). Cattle manure ash or calcium dihydrogen phosphate (CF) was incorporated into sandy soil at 10, 20, and 50 g P2O5 m−2. Two combinations of CMA and CF were tested at 20 g P2O5 m−2. Potassium rates followed K content in CMA applied at different rates of P equivalent to 19, 38, or 96 g K2O m−2. In four harvests, there was no significant difference in the total yields between CMA and CF treatments. The total P uptake was significantly lower in the CMA treatment than in the CF treatment, while it was not in the combined CMA and CF treatments. The P uptake in response to different extraction methods indicated that the extraction of P by 2% formic acid without sonication is recommended to predict P availability in CMA. The potassium uptake from CMA application was comparable to that from the KCl application, and excessive K occurred at 38 and 96 g K2O m−2. The grass tetany hazard ratio higher than 2.2 was observed at the beginning period at the lowest application rates of CMA and CF. In conclusion, the combination use of CMA and CF was better than the single use of CMA. Moreover, CMA would be an available K source, but the grass tetany hazard still needs to be considered in application rates and pretreatments.

RGB camera-based imaging of cerebral tissue oxygen saturation, hemoglobin concentration, and hemodynamic spontaneous low-frequency oscillations in rat brain following induction of cortical spreading depression.

To evaluate cerebral hemodynamics and spontaneous low-frequency oscillations (SLFOs) of cerebral blood flow in rat brain, we investigated an imaging method using a digital RGB camera. In this method, the RGB values were converted into tristimulus values in the CIE (Commission Internationale de l'Eclairage) XYZ color space, which is compatible with the common RGB working spaces. Monte Carlo simulation for light transport in tissue was then used to specify the relationship among the tristimulus XYZ values and the concentrations of oxygenated hemoglobin (CHbO), deoxygenated hemoglobin (CHbR), and total hemoglobin (CHbT) and cerebral tissue oxygen saturation (StO2). Applying the fast Fourier transform to each pixel of the sequential images of CHbT along the timeline, SLFOs of cerebral blood volume were visualized as a spatial map of power spectral density (PSD) at specific frequencies related to vasomotion. To confirm the feasibility of this method, we performed in vivo experiments using exposed rat brain during a cortical spreading depression (CSD) evoked by topical application of KCl. Cerebral hemodynamic responses to CSD such as initial hypoperfusion, profound hyperemia, and post-CSD oligemia and hypoxemia were successfully visualized with this method. At the transition to the hyperemia phase from hypoperfusion, CHbO and StO2 were significantly increased, which implied vasodilatation in arterioles and increased cerebral blood volume in response to CSD. In the wake of the hyperemic phase, CHbO and CHbT were significantly reduced to 25 ± 12% and 3.5 ± 1% of baseline, respectively, suggesting long-lasting vasoconstriction after CSD. In this persistent oligemia, StO2 significantly dropped to at most 23 ± 12% of the level before CSD, indicating long-lasting hypoxemia. The PSD value of SLFOs in CHbT for arteriole regions during CSD was significantly reduced to 28 ± 20% of baseline with respect to the pre-CSD level, which was correlated with the reduction in StO2. The results showed the possibility of RGB camera-based diffuse reflectance spectroscopy imaging for evaluating cerebral hemodynamics and SLFOs under normal and pathologic conditions.

Potato plants (Solanum tuberosum L.) are chloride-sensitive: Is this dogma valid?

Chloride sensitivity of the potato (Solanum tuberosum L.) cultivars Marabel and Désirée was investigated in two pot experiments (soil/sand mixture and hydroponics). It was tested whether there are differential effects of KCl and K2 SO4 application on tuber yield and tuber quality, and whether both potato cultivars differ in their chloride sensitivity. Tuber yield, dry matter percentage of the tubers, starch concentration and starch yield were not significantly affected by potassium source (K2 SO4 or KCl). After exposure to salt stress in hydroponics (100 mmol L-1 NaCl, 50 mmol L-1 Na2 SO4 , 50 mmol L-1 CaCl2 ) for 5 days, 3-week-old potato plants had significantly reduced shoot dry mass after NaCl and Na2 SO4 application. However, CaCl2 treatment did not significantly affect shoot growth, although the chloride concentration reached 65 to 74 mg Cl- mg-1 dry matter, similar to the NaCl treatment. In contrast, growth reductions were closely related to sodium concentrations, thus plants suffered sodium toxicity and not chloride toxicity. Both potato cultivars are chloride-resistant and can be fertilised with KCl instead of K2 SO4 without the risk of depression in tuber yield or tuber quality. The statement that potatoes are chloride-sensitive and that chloride has negative effects on yield performance needs reconsideration. © 2017 Society of Chemical Industry.

Direct Current Coupled Recordings of Cortical Spreading Depression Using Silicone Probes.

Electrophysiological assessment of infraslow (<0.1 Hz) brain activities such as cortical spreading depression (SD), which occurs in a number of pathologies including migraine, epilepsy, traumatic brain injury (TBI) and brain ischemia requires direct current (DC) coupled recordings of local field potentials (LFPs). Here, we describe how DC-coupled recordings can be performed using high-density iridium electrode arrays (silicone probes). We found that the DC voltage offset of the silicone probe is large and often exceeds the amplifier input range. Introduction of an offset compensation chain at the signal ground efficiently minimized the DC offsets. Silicone probe DC-coupled recordings across layers of the rat visual and barrel cortices revealed that epipial application of KCl, dura incision or pinprick TBI induced SD which preferentially propagated through the supragranular layers and further spread to the granular and infragranular layers attaining maximal amplitudes of ~−30 mV in the infragranular layers. SD at the superficial cortical layers was nearly two-fold longer than at the deep cortical layers. Continuous epipial KCl evoked multiple recurrent SDs which always started in the supragranular layers but often failed to propagate through the deeper cortical layers. Intracortical KCl injection into the infragranular layers evoked SD which also started in the supragranular layers and spread to the granular and infragranular layers, further indicating that the supragranular layers are particularly prone to SD. Thus, DC-coupled recordings with silicone probes after offset compensation can be successfully used to explore the spatial—temporal dynamics of SD and other slow brain activities.

Revealing the Saline Adaptation Strategies of the Halophilic Bacterium Halomonas beimenensis through High-throughput Omics and Transposon Mutagenesis Approaches

Studies on the halotolerance of bacteria are attractive to the fermentation industry. However, a lack of sufficient genomic information has precluded an investigation of the halotolerance of Halomonas beimenensis. Here, we describe the molecular mechanisms of saline adaptation in H. beimenensis based on high-throughput omics and Tn5 transposon mutagenesis. The H. beimenensis genome is 4.05 Mbp and contains 3,807 genes, which were sequenced using short and long reads obtained via deep sequencing. Sixteen Tn5 mutants with a loss of halotolerance were identified. Orthologs of the mutated genes, such as nqrA, trkA, atpC, nadA, and gdhB, have significant biological functions in sodium efflux, potassium uptake, hydrogen ion transport for energy conversion, and compatible solute synthesis, which are known to control halotolerance. Other genes, such as spoT, prkA, mtnN, rsbV, lon, smpB, rfbC, rfbP, tatB, acrR1, and lacA, function in cellular signaling, quorum sensing, transcription/translation, and cell motility also shown critical functions for promoting a halotolerance. In addition, KCl application increased halotolerance and potassium-dependent cell motility in a high-salinity environment. Our results demonstrated that a combination of omics and mutagenesis could be used to facilitate the mechanistic exploitation of saline adaptation in H. beimenensis, which can be applied for biotechnological purposes.