摘要:

This investigation was conducted to compare nutrients extracted by four different commercial soil testing kits with nutrients extracted by laboratory procedures commonly used in Southeastern United States soil testing laboratories. Ten soils with a range in pH and nutrient level were chosen for evaluation of the kits to separate the soils as deficient or sufficient in nutrient status.

ISSN:0010-3624    

DOI:10.1080/00103627909366925

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The feasibility of using a simple radiochemical method to determine the extent of formylation resulting from interaction of formic acid solutions with soil constituents was investigated. The interaction between formic acid‐l4C solvents and starch was used as a model reaction. Radioassay of 1 cm3formic acid solution by liquid scintillation counting in 10 cm3of the scintillator‐solubilizer Insta‐gel was found to be suitable. The method is simple to use and sample preparation is easy.

ISSN:0010-3624    

DOI:10.1080/00103627909366926

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103627909366927

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Diagnosis and yield prognosis model and method were developed on the basis of data from factorial field experiments on soybean (Glycine max(L) Merr.) conducted at AIT, Bangkok. Composition of N and P in the aerial parts of the plant at a fixed dry matter weight formed the basis of the model. The method included the determination of absolute and relative nutritional status of the individual nutrients expressed by diagnosis and the complete nutritional status of the young plant expressed by the final yield as yield prognosis.

ISSN:0010-3624    

DOI:10.1080/00103627909366928

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The quantity of Zn extracted from 25 samples of air‐dried soil was larger than that extracted from soils that were flooded for six weeks. The order of the quantity of Zn extracted from samples of air‐dried soils was: 0.1NHCl > EDTA + 1NNH4OAC > EDTA ‐ (NH4)2CO3> 1NNH4OAc, pH 4.8 > DTPA‐TEA, pH 7.30. The order of the quantity of Zn extracted from the flooded soils with four extracting solutions was: 0.1NHCl > 1NNH4OAc, pH 4.8 > EDTA‐(NH4)2CO3> DTPA‐TEA, pH 7.30. Flooding with distilled water resulted in an increase in the pH of all of the soil samples.

ISSN:0010-3624    

DOI:10.1080/00103627909366929

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Experiments were conducted to seek a better basis for soil testing of rice paddy soils. Soils were incubated under variable conditions of simulated flooding, and then extracted with DTPA5. The amounts of Cu, Zn, Mn and Fe extracted were sensitive to the imposed soil conditions. Good correlations between Zn extracted from simulated flooded soils and Zn uptakes by rice from flooded soils in pots, suggest that this approach to soil testing may be more useful for paddy soils than existing tests on air dried soils.

ISSN:0010-3624    

DOI:10.1080/00103627909366930

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

We studied the effects of liming on dry matter production, nutrient composition, and grain yields of wheat in field experiments conducted on two soil types at three locations during the 1976–77 and 1977–78 growing seasons. Lime sources were commercial agricultural lime, finely divided stack dust, and dolomitic limestone (which contained 10.6% Mg). Lime applied at 2,800 kg/ha in the 1976–77 and 10,750 kg/ha in the 1977–78 experiments provided Mg from the dolomite at rates of 300 and 1,140 kg/ha, respectively.

ISSN:0010-3624    

DOI:10.1080/00103627909366931

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

In the technique presented,35S was used to label the soil available sulfur pool in intact pasture cores, which were subsequently treated with different sulfur fertilizers. Dilution of the35S in the soil by sulfur released from the fertilizers was monitored by measuring the changes in specific radioactivity of sulfur in plants growing in the cores. The results showed the effects of fertilizer form, particle size and application rate on the supply of sulfur to plants. This technique will be useful for making direct comparisons of the ability of commercially available fertilizers to maintain the supply of sulfur to plants.

ISSN:0010-3624    

DOI:10.1080/00103627909366932

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The relationship between potassium concentration in the plant at various growth stages and the grain yield ofL. angustifoliuscv. Unicrop was derived from a rates and times of application of KCl field trial.

ISSN:0010-3624    

DOI:10.1080/00103627909366933

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

To examine sonic dispersion as an extraction procedure for DTPA micronutrient test, soil DTPA solution suspensions were sonicated to extract Fe, Zn, Mn, and Cu. The elements extracted after 15 or 60 seconds sonication were compared with those extracted after 1/2 or 2 hours shaking.

ISSN:0010-3624    

DOI:10.1080/00103627909366934

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor