ISSN:0010-3624    

DOI:10.1080/00103627309366454

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

Atonic absorption spectrophotometry was used to measure small amounts of Rb in the presence of relatively large amounts of K in plant material. Wet digestion with concentrated nitric acid provided good recoveries of Rb. A low temperature propane‐air flame and‐ a supporting electrolyte ofINHNO3+ 500 ppm Cs + 1000 ppm La were used to eliminate chemical and physical interferences of variable components of different plant parts and different plant species.

ISSN:0010-3624    

DOI:10.1080/00103627309366455

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

Two soybean varieties were grown at different P levels to test tolerance to high levels of P. When Hawkeye and PI54619–5–1 soybeans,Glycine max(L.) Merr. Bragg, were grown in solution culture with NH4H2PO4increasing from 10‐4Mto 3 × 10‐2M,yields of Hawkeye were decreased more by the highest P levels than were those of PI54619–5–1. The high P also resulted in larger concentrations of Zn, Cu, and other heavy metals in Hawkeye man in PI54619–5–1. Phosphorous concentrations were generally higher for Hawkeye than for the PI54619–5–1 soybeans. PI54619–5–1 leaves contained less of most metals than the Hawkeye.

ISSN:0010-3624    

DOI:10.1080/00103627309366456

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

The NO3‐N content of wheat samples collected in December and January did not increase with increasing rates of nitrogen, therefore no critical NO3‐N level could be established for these periods. The critical NO3‐N content of samples collected at the “joint”; stage of growth was 350 ppm.

ISSN:0010-3624    

DOI:10.1080/00103627309366457

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

Applied N and soil test K were negatively correlated with the incidence of Chocolate Spot (CS). Applied N was also negatively correlated with Northern Corn Leaf Blight (NCLB), but no relationship existed between soil test K and this disease. Levels of exchangeable K above 170 lbs/acre essentially eliminated the CS infection. Lodging of corn was positively correlated with applied N and negatively correlated with soil test K. Levels of soil test K above 170 lbs/acre markedly reduced the amount of lodging. Six different hybrids were included in this study. The hybrids showed significant differences in the incidence of the CS disease. Multiple regression equations indicated that corn yield:, were maximized at a level of 160 lbs/acre of applied N and a soil test of approximately 280 lbs/acre of K.

ISSN:0010-3624    

DOI:10.1080/00103627309366458

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

Prescribed fire to remove residue in a pine plantation on a sandy soil resulted in increases in pH, P, K and Ca in the top 20 cm of soil during the first 15 months following treatment.

ISSN:0010-3624    

DOI:10.1080/00103627309366459

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

Celery and head lettuce were grown on sphagnum peat with fertilizer treatments consisting of an N, a P and a K series. Each nutrient was applied at four rates in combination with constant rates of the other two.

ISSN:0010-3624    

DOI:10.1080/00103627309366460

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

Timothy was grown under greenhouse conditions with 6 levels of soil B and A pH values. No significant yield increases were obtained with added B, although values as low as 2.8 ppm B in the tissue were obtained. Boron toxicity symptoms on leaves were obtained with B additions at the rate of A mg/kg soil. Tissue B concentrations of greater than 102 ppm were associated with B toxicity symptoms and decreased yields. Liming decreased the B concentration of the leaf tissue; such decreases were more marked at higher rates than at lower rates of B. Liming the soil to pH 6.5 decreased the yield of timothy. However, the decreased yield at higher pH levels was not corrected by application of B as observed under similar conditions on forage legumes, but was probably caused by Mn deficiency.

ISSN:0010-3624    

DOI:10.1080/00103627309366461

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

A second order equation best described the relationship between exchangeable Mg and both total and acid‐soluble Mg in select temperate and tropical soils. The relationship between acid‐soluble and total Mg was linear. Soil types differ in their Mg contents. On a per unit weight of material bases the finer soil particles contained more than 95 percent of the total soil inorganic magnesium. In tropical soils, as in temperate soils, the total Mg content of surface horizons tends to decrease with severe weathering, soil erosion and movement of soil colloidal particles down the profile.

ISSN:0010-3624    

DOI:10.1080/00103627309366462

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

A field investigation was conducted to compare the efficacy of plowed‐down and disked‐in Zn as ZnSO4.H2O in correcting Zn deficiency of corn (Zea maysL.). The soil, Buchanan fine sandy loam, was nearneutral in pH and contained 0.7 ppm of EDTA‐extractable Zn and 1.4 ppm of dilute HCl‐H2SO4extractable P. Application of 6.72 kg Zn/ha as ZnSO4.H2O corrected Zn deficiency of corn plants on the soil. Corn grain yields and Zn concentrations in tissue samples indicated that the plowed‐down and disked‐in Zn were about equally effective in correcting Zn deficiency where the level of Zn application was 6.72 kg/ha.

ISSN:0010-3624    

DOI:10.1080/00103627309366463

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor