scholarly journals The increased yield of rice due application of high-potassium-NPK fertilizer to low-potassium-soil content

Author(s):  
N Istiqomah ◽  
C Tafakresnanto
1990 ◽  
Vol 258 (6) ◽  
pp. C1169-C1172 ◽  
Author(s):  
J. A. Halperin ◽  
C. Brugnara ◽  
T. Van Ha ◽  
D. C. Tosteson

We have recently reported that voltage-activated fluxes of Na, K, and Ca occur in human red blood cells [J.A. Halperin, C. Brugnara, M. Tosteson, T. Van Ha, and D. C. Tosteson. Am. J. Physiol. 257 (Cell Physiol. 26): C986-C996, 1989]. The cation permeability increases progressively as the membrane potential becomes more inside positive above +20 mV. In this paper we show that this effect also occurs in high-potassium (HK), but not in low-potassium (LK), sheep and dog red blood cells. This result suggests that the voltage-activated cation transport pathway is not the result of nonspecific dielectric breakdown of the lipid bilayer but, rather, relates to some membrane component, presumably a protein, that is expressed in HK human and sheep but not in LK sheep and dog red blood cells.


2009 ◽  
Vol 20 (24) ◽  
pp. 5051-5063 ◽  
Author(s):  
Bruna Barneda-Zahonero ◽  
Alfredo Miñano-Molina ◽  
Nahuai Badiola ◽  
Rut Fadó ◽  
Xavier Xifró ◽  
...  

Bone morphogenetic proteins (BMPs) have been implicated in the generation and postnatal differentiation of cerebellar granule cells (CGCs). Here, we examined the eventual role of BMPs on the survival of these neurons. Lack of depolarization causes CGC death by apoptosis in vivo, a phenomenon that is mimicked in vitro by deprivation of high potassium in cultured CGCs. We have found that BMP-6, but not BMP-7, is able to block low potassium–mediated apoptosis in CGCs. The neuroprotective effect of BMP-6 is not accompanied by an increase of Smad translocation to the nucleus, suggesting that the canonical pathway is not involved. By contrast, activation of the MEK/ERK/CREB pathway by BMP-6 is necessary for its neuroprotective effect, which involves inhibition of caspase activity and an increase in Bcl-2 protein levels. Other pathways involved in the regulation of CGC survival, such as the c-Jun terminal kinase and the phosphatidylinositol 3-kinase (PI3K)-Akt/PKB, were not affected by BMP-6. Moreover, failure of BMP-7 to activate the MEK/ERK/CREB pathway could explain its inability to protect CGCs from low potassium–mediated apoptosis. Thus, this study demonstrates that BMP-6 acting through the noncanonical MEK/ERK/CREB pathway plays a crucial role on CGC survival.


1974 ◽  
Vol 64 (5) ◽  
pp. 536-550 ◽  
Author(s):  
John R. Sachs ◽  
Philip B. Dunham ◽  
Donna L. Kropp ◽  
J. Clive Ellory ◽  
Joseph F. Hoffman

The characteristics of the interaction of Na-K pumps of high potassium (HK) and low potassium (LK) goat red blood cells with ouabain have been determined. The rate of inhibition by ouabain of the pump of HK cells is greater than the rate of inhibition of the pumps of LK cells. Treatment of LK cells with an antibody (anti-L) raised in HK sheep by injecting LK sheep red cells increases the rate of inhibition of the LK pumps by ouabain to that characteristic of HK pumps; reduction of intracellular K (Kc) in LK cells increases the rate at which ouabain inhibits their pumps and exposure of these low Kc cells to anti-L does not affect the rate of inhibition. There is considerable heterogeneity in the pumps of both HK and LK cells in the rate at which they interact with ouabain or the rate at which they pump or both. LK pumps which are sensitive to stimulation by anti-L bind ouabain less rapidly than the remainder of the LK pumps and exposure to antibody increases the rate at which ouabain binds to the sensitive pumps; the difference between the two types of pumps disappears if intracellular K is very low. The calculated number of ouabain molecules bound at 100% inhibition of the pump is about the same for HK and LK cells. Although exposure to anti-L increases the apparent number of ouabain binding sites in LK cells at normal Kc, it does not alter the apparent number of sites in LK cells when Kc has been reduced.


1971 ◽  
Vol 58 (1) ◽  
pp. 94-116 ◽  
Author(s):  
Philip B. Dunham ◽  
Joseph F. Hoffman

Red cells from high K sheep contained 82 mM K/liter cells and had a pump flux of 0.86 mM K/liter cells x hr; similarly, LK cells had 16.5 mM K/liter cells and a pump flux of 0.12 mM K/liter cells x hr. Using [3H]-ouabain, the relation between the number of ouabain molecules bound per cell and the concomitant per cent inhibition of the pump was found to be approximately linear for both HK and LK cells. The number of glycoside molecules necessary for 100 % inhibition of the pump was 42 for HK cells and 7.6 for LK cells, after correction for six nonspecific binding sites for each type of cell. The ratio of ouabain molecules/cell at 100 % inhibition was 5.5, HK to LK, and the ratio of the normal K pump fluxes was 7.2, HK to LK. The similarity of these ratios suggests that an important difference between HK and LK cells, determining the difference in pump fluxes, is the number of pump sites. The turnover times (ions/site x min) are 6000 and 4800 for HK and LK cells, respectively. The results also indicate a high specificity of binding of ouabain to pump sites.


1974 ◽  
Vol 63 (4) ◽  
pp. 389-414 ◽  
Author(s):  
John R. Sachs ◽  
J. Clive Ellory ◽  
Donna L. Kropp ◽  
Philip B. Dunham ◽  
Joseph F. Hoffman

The kinetic characteristics of the Na:K pump in high potassium (HK) and low potassium (LK) goat red cells were investigated after altering the intracellular cation concentrations. At low concentrations of intracellular K (Kc), increasing Kc at first stimulates the active K influx in HK cells, but at higher Kc the pump is inhibited. These results suggest that in HK cells Kc acts both at a stimulatory site at the inner aspect of the pump and by competition with intracellular Na (Nac) at the Na translocation sites. In LK cells, Kc inhibits the active K influx and the sensitivity of LK cells to inhibition is much greater than the sensitivity of HK cells. Exposure of LK cells to an antibody (anti-L), raised in an HK sheep by injection of LK sheep cells, increased the active K influx at any given Kc. The effect of the antibody was greater at higher intracellular K concentrations, and in cells with very low concentrations of K the antibody had little effect on the pump rate. The failure of anti-L to stimulate the pump in low Kc LK cells was not due to failure of the antibody to bind to the cells. Anti-L combining at the outer surface of the cell reduces the affinity of the pump at the inner surface for K at the inhibitory sites. The maximal pump rate in LK cells at optimal Na and K concentrations is less than the maximal pump rate of HK cells under the same circumstances.


1967 ◽  
Vol 47 (1) ◽  
pp. 39-46 ◽  
Author(s):  
V. V. E. St. Omer ◽  
W. K. Roberts

Balance studies were conducted with heifers weighing between 210–258 kg to determine effects of different dietary potassium levels, 156.6 (low), 439.4 (medium) and 1,086.8 (high) meq upon nutrient utilization. The low potassium ration produced an average negative potassium balance of 25.2 meq daily, while the other rations produced positive potassium balances. Urinary potassium excretion was markedly affected by potassium level while fecal potassium excretion was much less affected: in general, the higher the potassium intake, the higher the urinary and fecal potassium excretions. All heifers were in positive sodium balance and dietary level of potassium did not significantly influence either urinary or fecal excretion of sodium. Nitrogen balance was not significantly affected by treatment, but urinary ammonia excretion was significantly (P < 0.01) higher when the low potassium ration was fed. Water consumption and urine volume were significantly (P < 0.01) higher for the heifers fed high potassium, but water balance was not affected. Apparent digestibilities of energy, dry matter, nitrogen, crude fiber and ether extract were not significantly affected by treatment.Serum potassium levels were lower (P < 0.05) and phosphorus higher (P < 0.05) in heifers receiving the low than in heifers receiving the high level of potassium. Serum concentrations of sodium, chloride, calcium and magnesium were not significantly affected by dietary potassium.From the data, the potassium requirement for maintenance of the heifers was estimated to be 133 meq potassium daily per 100 kg body weight.


Plants ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 11 ◽  
Author(s):  
Yingdui He ◽  
Ruimei Li ◽  
Fei Lin ◽  
Ying Xiong ◽  
Lixia Wang ◽  
...  

Potassium plays an important role in enhancing plant resistance to biological and abiotic stresses and improving fruit quality. To study the effect of potassium nutrient levels on banana root growth and its regulation mechanism, four potassium concentrations were designed to treat banana roots from no potassium to high potassium. The results indicated that K2 (3 mmol/L K2SO4) treatment was a relatively normal potassium concentration for the growth of banana root, and too high or too low potassium concentration was not conducive to the growth of banana root. By comparing the transcriptome data in each treatment in pairs, 4454 differentially expressed genes were obtained. There were obvious differences in gene function enrichment in root systems treated with different concentrations of potassium. Six significant expression profiles (profile 0, 1, 2, 7, 9 and 13) were identified by STEM analysis. The hub genes were FKF1, HsP70-1, NRT1/PTR5, CRY1, and ZIP11 in the profile 0; CYP51 in profile 1; SOS1 in profile 7; THA, LKR/SDH, MCC, C4H, CHI, F3′H, 2 PR1s, BSP, TLP, ICS, RO, chitinase and peroxidase in profile 9. Our results provide a comprehensive and systematic analysis of the gene regulation network in banana roots under different potassium stress.


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