Evaluation of soil tests for the estimation of available sulphur

1977 ◽  
Vol 88 (1) ◽  
pp. 203-206 ◽  
Author(s):  
B. R. Arora ◽  
G. S. Sekhon

SUMMARYIn a glasshouse experiment, sulphur was applied to 22 soils as 35S-labelled gypsum. Estimates of available sulphur using different extractants were correlated with yield responses and sulphur uptakes by oats. The largest correlation coefficients were obtained with ‘A’ values and sulphur soluble in 0·5 M-NaHC03, 1% NaCl after heating and ammonium acetate–acetic acid. Critical levels of available sulphur obtained by relating these four methods to yield responses were 24·0, 22·0, 11·0 and 10·5 mgS/kg soil respectively.

1985 ◽  
Vol 25 (4) ◽  
pp. 863 ◽  
Author(s):  
EK Best ◽  
GK Manning ◽  
NJ Grundon

Tests with six solutions for extracting copper from soil (viz.: 1M ammonium acetate (CH3COONH4); 1M CH3COONH4 + 2% hydroquinone; 0. 5M ammonium oxalate [(NH4)2C2O4]; 0.005M diethylenetriaminepenta-acetic acid + triethanolamine + calcium chloride (DTPA + TEA + CaCl); 0.005MDTPA + 1M ammonium bicarbonate (NH4HCO3); and 0.01M ethylenediaminetetra- acetic acid (EDTA) + 1M NH4HCO3) were examined in both glasshouse and field studies for their ability to predict the responsiveness to copper fertilizer of wheat grown on a wide range of Queensland soils. The ammonium-acetate-based solutions did not extract measurable amounts of copper from soil. The usefulness of the remaining solutions was in the order EDTA-NH4HCO3>DTPA-NH4HCO3 >> DTPA-TEA-CaCl2 > (NH4)2C2O4. The EDTA-NH4HC03 method is recommended for identifying copper-responsive wheat soils in southern Queensland, and the suggested critical levels for dry matter production and grain yield are 0.4 and 0.3 ppm Cu respectively.


1990 ◽  
Vol 30 (4) ◽  
pp. 557 ◽  
Author(s):  
JD Armour ◽  
AD Robson ◽  
GSP Ritchie

Navy beans (Phaseolus vulgaris cv. Gallaroy) were grown with 7 rates of zinc (Zn) in a Zn-deficient gravelly sandy loam in a glasshouse experiment. The plant shoots were harvested 31 days after sowing and the Zn concentration in each of 4 plant parts (YL, young leaf; YOL, young open leaf; YFEL, youngest fully expanded leaf; and whole shoots) was related to the fresh weight of the shoots. The critical Zn concentrations (mgtkg) in the plant parts determined by the 2 intersecting straight lines model were 21.1 for YL (r2 = 0.66), 17.1 for YOL (r2 = 0.83), 10.6 for YFEL (r2 = 0.91) and 12.5 for the whole tops (r2 = 0.88). The YFEL was selected as an appropriate diagnostic tissue because it is readily identifiable in the field and had the highest 1.2 with fresh weight. In a second glasshouse experiment, the critical Zn concentration in the YFEL and 5 soil tests were evaluated for their ability to predict the Zn status of navy beans. There were 13 soils from sands to clays with a wide range of chemical properties. The soil tests were 0.1 mol/L HCl, DTPA, EDTA, dilute CaCl2 and soil solution Zn. The concentration of Zn in the YFEL correctly predicted Zn deficiency or adequacy in about 77% of samples. The results from both experiments showed that a critical Zn concentration of 10-11 mg/kg in the YFEL can be used to diagnose the Zn status of Gallaroy navy beans. It was not possible to recommend a single soil test for prediction of the relative yield of navy beans. A combination of quantity (HCl, EDTA, DTPA) and intensity (soil solution, 0.002 mol/L CaCl2, 0.01 mol/L CaCl2) parameters were able to explain most of the variation in the Zn concentration of the YFEL, a more sensitive measure of nutrient availability than relative yield. EDTA-Zn in combination with 0.01 mol/L CaCl2-Zn explained 90% of the variation in the Zn concentration in the YFEL, while HCl- or DTPA-Zn and 0.01 mol/L CaCl2 explained about 80% of the variation. As soil solution Zn was significantly correlated with 0.002 and 0.01 mol/L CaCl2-Zn (r = 0.75, P<0.01; r = 0.62, P<0.05, respectively), CaCl2-Zn may be used as a more convenient measure of Zn intensity than soil solution Zn.


1978 ◽  
Vol 18 (91) ◽  
pp. 243 ◽  
Author(s):  
AJ Montgomery ◽  
G Rubenis

The level of soil phosphorus and the response of irrigated perennial pasture to phosphorus fertilizer were measured on 33 sites in the Goulburn Valley of northern Victoria. Eleven of the 33 sites were found to have Olsen P values above 10 p.p.m. and Colwell P values above 30 p.p.m. Of these 11, 9 did not give a pasture response to superphosphate and 2 gave a relatively small response. Functions of the form Y = a - be-CX (where Y = total pasture yield over 12 months (t ha-1), X = rate of superphosphate application (t ha-1), and a, b and c are constants respectively denoting maximum yield, maximum response, and the rate at which maximum yield is approached) were fitted to the yield data from those sites at which a response did occur. b was found to be correlated with a number of soil tests, the highest correlation coefficient being -0.74 for Colwell P. a was significantly correlated with some tests (P < 0.01) but was generally less predictable, and c gave very low correlation coefficients with all soil tests.


1974 ◽  
Vol 29 (7-8) ◽  
pp. 552-555 ◽  
Author(s):  
Purshottam S. Kendurkar ◽  
Ram S. Tewari

Reactions of N-pyridinium phenancylides with different a, β-unsaturated ketones give 2,4,6-triarylsubstituted pyridines, 2,6-diphenyl-4-(2-pyridyl) pyridines, 2-benzylidene-4,6-diphenyl pyridines and 2,4,6-triphenyl-3-bromopyridine. Ammonium acetate in acetic acid was used as cyclization agent. The structure of the products are supported by IR and NMR spectra.


2001 ◽  
Vol 56 (10) ◽  
pp. 1074-1078 ◽  
Author(s):  
Samia Michel Agamy ◽  
Mervat Mohammed Abdel-Khalik ◽  
Mona Hassan Mohamed ◽  
Mohammed Hilmy Elnagdi

Enaminones react with a variety of active methyl and methylene reagents in presence of ammonium acetate to yield functionally substituted pyridines in good yields. The reaction proceeded via initial Michael addition across the double bond followed by cyclization. The reaction of enaminone with aromatic aldehyde in acetic acid/ammonium acetate afforded the dihydropyridine that was oxidized to the corresponding pyridine.


1975 ◽  
Vol 15 (72) ◽  
pp. 93
Author(s):  
B Palmer ◽  
VF McClelland ◽  
R Jardine

The relationships between soil tests for 'plant available' phosphate and wheat yield response to applied superphosphate were examined and the extent to which these relationships were modified by other soil measurements was determined. Soil samples and wheat yield data were obtained from experiments conducted in the Victorian wheat belt. The sites were grouped into four relatively uniform classes using soil pH measurement and geographic location. The soil test values differed widely and were accountable for by the soil characteristics measured. However, the overall and within group yield responses to applied superphosphate could not be accounted for in terms of either the soil test value or the associated chemical measurements. By inference, yield response was clearly dependent on factors other than those determining the results of soil tests.


1983 ◽  
Vol 23 (121) ◽  
pp. 192 ◽  
Author(s):  
SM Bromfield ◽  
RW Cumming ◽  
DJ David ◽  
CH Williams

Three methods of estimating available manganese and aluminium status in acid soils were compared on three groups of soils from the Pejar district near Goulburn, New South Wales in which differences in pH had been brought about by different periods under subterranean clover pasture. Managanese extracted by 0.01 M calcium chloride gave the best correlation with the manganese concentration in rape and subterranean clover grown in pot culture, and provided the best index of available manganese. Soil solution manganese was inferior to CaCl2-extractable manganese and was more difficult to determine. Extraction with neutral ammonium acetate was unsatisfactory because this reagent overestimated available forms of manganese in soils containing high levels of reactive manganese. Aluminium extracted by 0.01 M CaCl2 was well correlated with exchangeable aluminium and with percentage aluminium saturation of the effective cation exchange capacity. None of the three measures of aluminium status alone was an effective index for predicting lime response by rape on these soils because both manganese and aluminium status were involved in this response. These three parameters were equally effective in multiple regressions for yield responses of rape to lime. Because of its relative ease of determination, CaCl2 extraction is preferred as a practical measure of aluminium status. Aluminium interacted with and increased the toxic effects of manganese in rape. Thus CaCl2-extractable manganese alone only provided a satisfactory index of a 'critical' value for manganese toxicity in rape for soils low in available aluminium. Subterranean clover was only slightly affected by aluminium and manganese levels in these soils, and manganese toxicity symptoms were only observed on soils containing 50 ppm or more CaCl2-extractable manganese. Nodulation failure in pots occurred in all soils with pH below 5.2 (water) or below 4.3 in CaCl2, whereas nodulation was normal when these soils were treated with CaCO3 to raise the pH to 5.8-6.0 (water). With one exception nodulation appeared adequate at field sites from which soils showing nodulation failure in the glasshouse had been collected.


2018 ◽  
Vol 101 (6) ◽  
pp. 1961-1966 ◽  
Author(s):  
H H Wendy Yang ◽  
Adrian Weisz

Abstract Specifications in the U.S. Code of Federal Regulations for the color additive D&C Red No. 17 (R17, Colour Index No. 26100) limit the levels of the dye’s intermediates, aniline (AN), 2-naphthol (β-naphthol, BN), and 4-aminoazobenzene (4AAB), to 0.2, 0.2, and 0.1%, respectively. The present work reports the development and application of an ultra-HPLC method for the quantitative determination of these impurities in R17. A 1.7 μm particle size C-18 column was used with 0.2 M ammonium acetate and acetonitrile as the eluents. AN, BN, and 4AAB were quantified by using six-point calibration curves with data points (w/w) ranging from 0.01 to 0.25% for AN, 0.01 to 0.24% for BN, and 0.01 to 0.19% for 4AAB. The correlation coefficients ranged from 0.9992 to 0.9999. Limits of detection for the analytes ranged from 0.002 to 0.01%. Recoveries of the analytes ranged from 99.5 to 102%. Relative standard deviations ranged from 0.482 to 1.262%. The new method was applied to analyze portions from 22 batches of R17 submitted to the U.S. Food and Drug Administration for certification. It was found to be simpler to implement, faster, and more sensitive than the older gravity-elution column chromatography method, which it has replaced.


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