摘要:

Calcium was extracted from leaves sequentially with water, 0.5M sodium nitrate, 2M acetic acid and 2M hydrochloric acid. Water and hydrochloric acid removed well defined fractions; water soluble calcium was mostly present in complexed form; hydrochloric acid removed only calcium oxalate. The results show that some oxalic acid may be produced by acid hydrolysis of plant constitutents during extraction with hydrochloric acid.

ISSN:0010-3624    

DOI:10.1080/00103627709366747

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A potassium specific‐ion electrode equiped with a “sensing module” was compared with atomic absorption for potassium determination in plant tissue. The potentiometric readings were stable and reproducible, and were of the same order of magnitude as those obtained by atomic absorption. The correletion coefficient obtained between the two analytical methods were highly significant; but it was higher for corn leaves, sugarbeet leaf‐blades and petioles respectively.

ISSN:0010-3624    

DOI:10.1080/00103627709366748

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Ammonia and chloride electrodes were used to measure cation exchange capacity (C.E.C.) on a selection of Victorian soils. The C.E.C. values obtained using these electrodes correlated closely with the values obtained using established titrimetric procedures. The electrode method is preferred for subsequent soil studies because it is rapid, simple and less expensive, whereas titrimetric analyses require separate determination of ammonia and chloride ion which involve preparation of numerous reagents and standards.

ISSN:0010-3624    

DOI:10.1080/00103627709366749

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Soil samples were taken at frequent intervals in 1975 and 1976 from a factorial set of lime ‐K treatments initiated in December 1970 to determine the effect time of sampling has on K soil test values. Previous work at this site had shown wide fluctuations in K soil test values due to sample time thus necessitating a more detailed study than was previously made. Such information is necessary if accurate K fertilizer recommendations are to be made. Samples from 28 unfertilized plots showed that months of sampling significantly affected K soil test values. Soil test values for K were highest in late May and declined as the growing season progressed, remaining low until the relatively higher exchangeable K was re‐established the following spring.

ISSN:0010-3624    

DOI:10.1080/00103627709366750

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Sulfur accumulation in young soybean plants tended to follow the pattern reported for P differing only in quantity. Soybean stems tended to have a more constant S concentration over time than did leaves or petioles.

ISSN:0010-3624    

DOI:10.1080/00103627709366751

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103627709366746

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor