摘要:

Cassava main stem barks from two experiments in which similar fertilizers were applied directly in a 2 confounded factorial design were analyzed and the bark nutrients used as a guide to cassava nutrition. The application of multiple regression analysis to the respective root yields and bark nutrient concentrations enable nutrient levels and optimum adjusted root yields to be derived. Differences in bark nutrient concentrations reflected soil fertility levels. Bark analysis and the application of multiple regression analysis to root yields and bark nutrients appear to be useful tools for predicting fertilizer recommendations for cassava production.

ISSN:0010-3624    

DOI:10.1080/00103627909366964

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A colorimetric method using the azomethine H reagent is described for determining boron in an acid extract of plant tissue ash. The method consistently gave the certified value of 33±3 ppm B for NBS orchard leaf reference material No. 1571 with 3.2% coefficient of variation. Samples were dry ashed and the ash extracted in 10 ml 0.36 N H2SO4for 1 hr. at room temperature. Several acidic extractants and extracting conditions were compared which gave the certified value, but involved heating and readjusting the final volume.

ISSN:0010-3624    

DOI:10.1080/00103627909366965

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Concentrations of arsenic, bismuth, lithium and selenium were determined by atomic absorption spectrophotometry in 32 samples of commercial fertilizers from various manufacturers and distributors.

ISSN:0010-3624    

DOI:10.1080/00103627909366966

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The rates of applied phosphorus required for 90% maximum yield ofDesmodiim intortumcv. Greenleaf were calculated from pot experiments using 24 fertilized and unfertilized soils from the Atherton Tableland, Queensland, Australia.

ISSN:0010-3624    

DOI:10.1080/00103627909366967

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The profile distribution of total, DTPA‐ and 0.1 N HC1‐extractable Zn was determined in 11 Nigerian soil profiles formed on various parent Materials including the coastal plain sands, shales, basalt, granite and banded gneiss.

ISSN:0010-3624    

DOI:10.1080/00103627909366968

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Some batches of phosphoric acid contain impurities that affect colorimetric determination of urea in soil extracts by the method of Douglas and Bremner, which involves measurement of the red color formed when an aliquot of extract is heated with diacetyl monoxime and thiosemicarbazide in the presence of phosphoric and sulfuric acid. A modification of this colorimetric procedure is described that permits use of phosphoric acid containing these impurities and allows accurate and precise determination of urea in soil extracts.

ISSN:0010-3624    

DOI:10.1080/00103627909366969

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

‘Carina’ rose was grown on seven different rootstock clones. These, combinations were tested for effect on flower production and mineral content of the leaves when grown in fumigated ground beds in an evaporatively cooled plastic greenhouse. Plants growing onR.odorataISU 5710–2 produced the highest flower yields followed byR.fortunianaand R.manettiwhileR.multifloraISU 62–5 produced the lowest number of blooms. Rootstocks caused large differences in the levels of some minerals in the leaves.R.fortunianacaused a Mn accumulation that was five times the quantity developed byR.odoratabut this did not seem to be related to flower production. However,R. odoratawas a superior accumulator of K and under conditions of relatively low supplyR.fortunianaand R.odoratawere good accumulators of N and K. These factors were related to flower yield.

ISSN:0010-3624    

DOI:10.1080/00103627909366970

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Effect of incubation and microbial inhibition at field capacity level on changes in DTPA‐extractable Mn in acidic, neutral, and alkaline soils was examined. Incubation decreased and microbial inhibition increased the level of Mn in soils with high pH (>5.7) and high microbial activity. The change was apparently partially associated with microbes since the level of Mn did not change in soils with low microbial activity and/or low pH.

ISSN:0010-3624    

DOI:10.1080/00103627909366971

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103627909366963

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor