摘要:

Tolerances to Fe and Mn were determined with Bragg and Forrest (Mn‐intolerant) and T203 and Lee (Mn‐tolerant) soybean (Glycine max. (L.). Bragg was Fe efficient; Forrest and T203 were equally Fe‐inefficient plants. The soybeans were grown in nutrient solutions with 1.0 and 2.0 mg Fe/liter, and with 0.33 and 5.1 mg Mn/liter as variables, respectively. Bragg soybeans developed Fe toxicity symptoms with 2.0, but not with 1.0 mg Fe/liter. Forrest, Lee, and T203 did not develop Fe toxicity symptoms on either treatment. Bragg and Forrest soybean developed more severe Mn‐toxicity symptoms than Lee or T203 soybean when grown on nutrient solutions with 5.1 mg Mn/liter. Approach grafts showed that Mn tolerance appears to be controlled in the plant tops. Both Mn‐intolerant and tolerant soybean tops contained about the same concentration of Mn, but Mn‐tolerant tops contained more K and roots contained less Fe than Mn‐intolerant tops and roots. When Fe and Mn toxicities are not economically correctable, tolerant soybean varieties may be selected in order to make the plant compatible with the soil.

ISSN:0010-3624    

DOI:10.1080/00103627709366695

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103627709366694

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Aluminum in soil saturation extracts and exchangeable Al determined byNKCl extraction were studied using a large number of Ultisol and Alfisol samples from West Africa.

ISSN:0010-3624    

DOI:10.1080/00103627709366696

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A method has been devised for reproducibly separating from soils minimally altered, clay‐size soil organic‐mineral particles (SO‐MPs) by water dispersion and density centrifugation. Active surfaces of SO‐MPs so obtained should represent more closely those actually interfacing with root systems and microbes than the chemically cleaned clay or humic materials conventionally obtained in laboratory prepartions. The method reduces heterogeneity within given size fractions of SO‐MPs, which is desirable for studying relationships between composition and properties of minimally altered soil “fines”.

ISSN:0010-3624    

DOI:10.1080/00103627709366697

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The uptake of Pb by young, greenhouse grown corn plants from roadside soil samples was found to be not only dependent upon the total amount of Pb in the soil, but also upon the amount of Pb in the soil relative to the soils capacity to sorb Pb. This is in agreement with the uptake of Pb by corn grown on soils amended with PbCl2, although plant accumulation of Pb from roadside soils was much less than from PbCl2amended soils at comparable Pb concentrations. The use of crushed limestone as a road building material which results in high soil pH values next to the roadside is probably responsible for the reduced plant availability of Pb in the roadside soils.

ISSN:0010-3624    

DOI:10.1080/00103627709366698

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

In a greenhouse experiment corn plants were harvested 24 and 31 days following emergence from pots containing Bloomfield loamy sand (Psammentic Haplaudalf). Soil P was 140 kg/ha, exchangeable K was 220 kg/ha, and soil pH was 6.0. The soil CEC was 2.3 meq/100 g. Boron, Cu, Mn, and Zn were determined with emission spectroscopy. Treatment combinations were a factorial arrangement of 0, 2.5, and 5 μg/g of Cd and 0, 125, and 250 μg/g of Pb.

ISSN:0010-3624    

DOI:10.1080/00103627709366699

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Phosphate depletion zones around roots of cabbage and lettuce grown in two soils of differing phosphate sorption capacity were observed by autoradiography using P techniques.

ISSN:0010-3624    

DOI:10.1080/00103627709366700

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The effect of water stress on acetylene reduction (symbiotic nitrogen fixation) byRhizobium japonicumand soybean plants grown in silica sand was evaluated. Optimum water contents for acetylene reduction (nitrogen fixation) by the nitrogenase of the soybean root nodules were 60 to 80% of the moisture holding capacity of the sand.

ISSN:0010-3624    

DOI:10.1080/00103627709366701

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

An experiment was conducted to evaluate extraction methods for the determination of nitrate in a synthesized pine bark substrate. It was found that prior to nitrate determination, oven dryino of the pine bark sample was necessary followed by rewetting and extraction in a vacuum for 72 hours. Using this technique, about 65% of applied nitrate was recovered.

ISSN:0010-3624    

DOI:10.1080/00103627709366702

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103627709366693

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor