LABORATORY AND GREENHOUSE STUDIES ON EFFECT OF LIME AND OTHER AMENDMENTS ON WATER-SOLUBLE BORON IN SOIL

1958 ◽  
Vol 38 (1) ◽  
pp. 27-35 ◽  
Author(s):  
R. F. Bishop ◽  
R. L. Cook

Greenhouse and laboratory experiments were used to study the effect of various soil amendments on the water-soluble boron content of a strongly acid soil.In the greenhouse, using ladino clover as the test crop, liming reduced boron availability as measured by soil and plant analysis. Calcium-boron ratios in the clover ranged from approximately 550:1 to 2000:1 and there was a significant correlation between the water-soluble boron in the soil and the boron content of the clover.In the laboratory studies calcium and magnesium carbonates were equally effective in decreasing water-soluble boron in soil. Gypsum was ineffective. Manure or alfalfa hay increased the water-soluble boron content of soil in proportion to the amounts applied. Applications of sodium hydroxide, resulting in a range of soil pH values from 4.82 to 9.72, were accompanied by decreases in water-soluble boron until a pH of approximately 8.0 was reached. Above this point water-soluble boron increased. At comparable pH values of approximately 7.0 or less, sodium hydroxide caused a smaller reduction in water-soluble boron than did either calcium or magnesium carbonate.

1967 ◽  
Vol 47 (3) ◽  
pp. 203-210 ◽  
Author(s):  
L. B. MacLeod ◽  
L. P. Jackson

The concentration of water-soluble and exchangeable aluminum was determined in the 0–15-, 15–23-, 23–30- and 30–45-cm depths of a Podzol limed to provide surface soil pH values ranging from 4.5 to 7.2. Both soluble and exchangeable Al decreased with increasing soil pH. Soluble Al ranged from 5.7 ppm at pH 4.4 with high fertilization to 0.3 ppm at pH 6.5 with similar fertilization. Increasing the rate of fertilization at pH 4.5 raised the soluble Al from 2.6 to 5.7 ppm. Fertilization still doubled the soluble Al in soil at pH 5.1 but had little effect as the pH was raised further to 5.8 and 6.5. Soluble Al in the subsoil samples was less than in surface soil samples at the same pH, while with exchangeable Al, the concentration was greater in the subsoil than in the surface soil samples.There was not a direct relationship between pH and soluble Al, although the highest soluble Al concentrations occurred at lowest soil pH levels. Analyses of 30 representative samples of surface soil taken from farmers' fields showed that the soluble Al concentration at pH 4.0 ranged from 3.5 to 4.8 ppm, while at a pH of 5.0 it ranged from 0.2 to 2.8 ppm. The concentrations of soluble Al in many of these soils exceeded the levels previously shown by nutrient solution experiments to severely restrict growth of legumes and some varieties of barley.


Weed Science ◽  
1988 ◽  
Vol 36 (1) ◽  
pp. 78-83 ◽  
Author(s):  
K. A. Renner ◽  
W. F. Meggitt ◽  
D. Penner

Adsorption of14C-imazaquin {2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinolinecarboxylic acid} and imazethapyr [2-(4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl)-5-ethyl-3-pyridinecarboxylic acid] to soil increased as soil pH decreased from 8.0 to 3.0 in laboratory studies. Significantly more imazethapyr3(AC-263,499) than imazaquin was adsorbed at soil pH levels 3.0 and 5.5, while the greatest difference in adsorption behavior between the two herbicides was observed at a soil pH of 5.5. In greenhouse studies, phytotoxicity to corn (Zea maysL.) was greater for imazaquin than AC-263,499 applied at 26 and 53 g ai/ha. There were significant pH by herbicide and pH by rate interactions, but in trend analysis only a small proportion of the corn response (r2= 0.01 to 0.35) was attributed to increasing soil pH values. In field studies where imazaquin was applied to soil pH levels of 4.2 to 4.8, 5.4 to 5.5, and 5.8 to 6.2, injury to corn across all pH levels decreased as the time delay between herbicide application and corn planting increased. There was no significant effect of soil pH on imazaquin injury to corn planted in July or August. Decreased injury from imazaquin was observed in 1985 on corn planted in June on the soil pH of 5.8 to 6.2. Imazaquin injury was less for June-planted corn in 1984 than in 1985, across all soil pH levels.


Soil Research ◽  
1979 ◽  
Vol 17 (2) ◽  
pp. 367 ◽  
Author(s):  
RPS Chauhan ◽  
CPS Chauhan

During laboratory studies it was noted that water-soluble carbonate plus bicarbonate interferes with the determination of gypsum requirement (GR) by Schoonover's method and has significant correlation with the latter (r = 0.89). The interference of carbonate and bicarbonate can be eliminated through their precipitation as magnesium carbonate. A modified method to this effect is suggested hereby, and values of GR determined by this method are quite close (r = 0.99) to those of exchangeable sodium and give a fair approximation to it.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Wim Van den Berg ◽  
Jan Vos ◽  
Johan Grasman

The second order Akaike information criterion was used for the assessment of 139 regression models for three responses of potato test crops: (a) incidence ofSpongospora subterraneaon the harvested tubers, (b) percentage of haulms infected withVerticillium dahliae,and (c) tuber yield. Six variables that are likely related to the response variables were taken into consideration: soil infestations of the fungusVerticillium dahliaeand of three nematode species (Globodera pallida,Trichodoridae,andMeloidogynespp.) and, furthermore, soil pH and water soluble phosphor (P). Interactions betweenV. dahliaeand the three nematode species were included as well. Based on multimodelling, predictors are given a weight from which one may decide about the need to include them in a prediction of crop yield. The most important predictors were soil infestation levels ofV. dahliaeandG. pallidaand soil pH. The outcome also showed that tubers suffered more fromS. subterraneafor higher soil pH values. Finally, yield reduction from the presence ofV. dahliaewas enhanced by the presence of higher densities ofG. pallida.


1998 ◽  
Vol 78 (3) ◽  
pp. 477-479 ◽  
Author(s):  
C. J. Westman ◽  
S. Jauhiainen

Forest soil pH in southwest Finland was measured with identical sampling and analysing methods in 1970 and 1989. The acidity of the organic humus layer increased significantly as pH values measured on water and on salt suspensions decreased between the two sampling dates. For the mineral soil layers, no unambiguous trend was found. pH values measured on salt suspension tended to be unchanged or lower, while pH on water suspension in some soil layers were even higher in 1989 than in 1970. Key words: pH, repeated sampling


1967 ◽  
Vol 45 (7) ◽  
pp. 1175-1183 ◽  
Author(s):  
Roberto Umaña

The effect of the homogenization procedure, the centrifugation scheme, and the composition of the suspension medium on the distribution of nuclear volumes has been studied.It has been shown that the Waring Blendor not only destroys a greater number of the nuclei during homogenization, but also that this destruction is a selective one. At neutral pH values, no direct relationship appears to exist between the DNA content of the nuclei and their density. For this reason, purification in concentrated sucrose solutions produces a selective loss of the lighter nuclei, which includes small diploid stromal nuclei and some of the larger polyploid type of parenchymal nuclei.The study of the effect of increasing the calcium and magnesium ion concentrations (from 0.001 to 0.005 M) on the nuclear distribution showed that these ions produce a selective shrinkage and condensation of the nuclei, probably through different mechanisms.


1987 ◽  
Vol 65 (1) ◽  
pp. 210-213 ◽  
Author(s):  
A. H. Fitter ◽  
W. F. J. Parsons

Soil pH and concentrations of N and P in leaves of Dryas drummondii were measured on recessional moraines of the Athabasca Glacier, Alberta. Soil pH declined by 0.5 units per 100 years under Dryas but remained steady on bare ground. Water-soluble N and P levels in soil remained low at all stages, but N was higher under Dryas patches. Leaf P and N declined in the early stages of succession but increased later. This increase may represent the initiation of biotic N and P cycles in soil. These patterns contrast with those reported for other moraine successions.


Author(s):  
Л.А. МАРЧЕНКО ◽  
Т.Н. БОКОВИКОВА ◽  
Е.В. ЛИСОВАЯ ◽  
С.А. ИЛЬИНОВА ◽  
Е.П. ВИКТОРОВА

Исследована возможность применения яблочной кислоты (ЯК) в качестве гидратирующего агента для перевода негидратируемых форм фосфолипидов в гидратируемые. Выбор ЯК обусловлен ее стоимостью, которая в 1,5 раза меньше стоимости янтарной кислоты, широко применяемой в качестве гидратирующего агента, а также большей доступностью с точки зрения промышленного производства. Исследование процесса комплексообразования и определение состава комплексных соединений ЯК с ионами кальция и магния осуществляли методом потенциометрического титрования. Установлено, что внесение в раствор ЯК ионов кальция и магния приводит к снижению значений рН, что свидетельствует о наличии комплексообразования в указанных системах. Наиболее устойчивыми являются комплексы ионов кальция и магния с непротонированным лигандом при соотношении Ме2 : лиганд 1 : 1. В процессе комплексообразования ионы Ca2 и Mg2 вытесняют протоны только карбоксильных групп ЯК, которая с ионами кальция образует более устойчивые комплексы, чем с ионами магния. Показано, что устойчивость комплексов ЯК с ионами кальция и магния значительно выше, чем устойчивость комплексов фосфатидилсеринов и фосфатидных кислот с указанными ионами. Использование водных растворов ЯК в качестве гидратирующего агента позволит повысить эффективность процесса гидратации и увеличить выход фосфолипидов и, следовательно, готового продукта лецитина. The possibility of using malic acid (MA) as a hydrating agent for converting non-hydrated forms of phospholipids into hydrated ones has been investigated. The choice of MA is due to its cost, which is 1,5 times less than the cost of succinic acid, as well as greater availability from the point of view of industrial production. The study of the complexation process and determination of the composition of complex compounds of MA with calcium and magnesium ions was carried out by the method of potentiometric titration. It was found that the introduction of calcium and magnesium ions into the MA solution leads to a decrease in pH values, which indicates the presence of complexation in these systems. Complexes of calcium and magnesium ions with an unprotected ligand at a ratio of ME2 : ligand 1 : 1 are the most stable. In the process of complexing, Ca2 and Mg2 ions displace protons only of the carboxyl groups of MA, which forms more stable complexes with calcium ions than with magnesium ions. It is shown that the stability of MA complexes with calcium and magnesium ions is significantly higher than the stability of phosphatidylserine and phosphatidic acid complexes with these ions. Using water solutions of MA as a hydrating agent will increase the efficiency of the hydration process and increase the yield of phospholipids and, consequently, the finished product lecithin.


Author(s):  
Hermann C. de Albuquerque ◽  
Geraldo R. Zuba Junio ◽  
Regynaldo A. Sampaio ◽  
Luiz A. Fernandes ◽  
Fabiano B. S. Prates ◽  
...  

ABSTRACTThis study aimed to evaluate the residual effect of sewage sludge fertilization on yield and nutrition of sunflower in its second cycle. The experiment was carried out from April to August 2012. The treatments consisted of four doses of sewage sludge (0, 10, 20 and 30 t ha-1, dry basis) applied in the first cycle of sunflower, distributed in a randomized block design, with six replicates. Sunflower stem diameter, plant height, capitulum diameter and yield increased with the increment in sewage sludge doses, with maximum values observed with the dose of 30 t ha-1. The contents of calcium and magnesium in the soil, pH, sum of bases, effective and potential cation exchange capacity and base saturation increased, while potential acidity and the contents of manganese and iron in the leaves decreased, with the increment in the residual doses of sewage sludge. There was a reduction in yield and growth characteristics of sunflower in the second cycle; thus, additional fertilization with sewage sludge is recommended in each new cycle.


1962 ◽  
Vol 40 (1) ◽  
pp. 1019-1024 ◽  
Author(s):  
Seiichi Yoshida

A water-soluble pigment excreted from Serratia marcescens has been purified by precipitation with ammonium sulphate, dialysis, and ultracentrifugation at different pH values. The purified pigment showed a single band in the ultracentrifuge and by electrophoretic analysis at several pH values. An average molecular weight of 5 × 106 was calculated from light-scattering measurements. This pigment is composed of carbohydrate and protein combined with prodigiosin, and several properties of the complex are described.


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