摘要:

Optimal yields have been obtained by establishing and maintaining a specified ionic root environment. An Intensity and Balance Concept has been developed, utilizing intensity and balance soil testing procedures. Total salts and the proportionate concentration of cations and anions in a soil saturation extract are used to evaluate the ionic environment. That combination of ionic concentrations which gives the best yield is used as the standard forming the basis for fertilizer recommendations. Consistently high yields of fresh market tomatoes from 96,000 to 117,000 kg/ha were produced during 9 seasons using the procedures described where ionic environments were established and maintained. During these same seasons, the average Florida production for fresh market tomatoes was considerably less, ranging from 10,000 to 50,000 kg/ha.

ISSN:0010-3624    

DOI:10.1080/00103627009366257

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Corn(Zea maysL.) was grown for three consecutive years on Congaree loam to measure the effects of rates of N, P, and K fertilization and irrigation on the nutrient concentration of leaves, the level of available K in the soil, and on the yield of corn. Plant nutrients consisting of 0, 56, 140, 224, and 280 kg N/ha; 0, 15, 37.5, 60, and 75 kg P/ha, and 0, 28, 70, 112, and 140 kg K/ha were applied in a central composite rotatable design in each of the three years. All plant residue was removed each year when the corn was harvested, and the plots remained fallow during the winter months. One half of the experiment was irrigated when there was a 50% depletion of available soil moisture in the 0‐ to 46‐cm soil depth.

ISSN:0010-3624    

DOI:10.1080/00103627009366258

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Boron analysis of plant tissue by the quinallzarin procedure has been adapted to the Technicon AutoAnalyzer system. Results obtained are comparable to those by the curcumin method for evaluating the boron status of the plant. Details of the mechanical assembly are presented and precautions to be observed are discussed. The suggested procedure permits the analysis of 30 samples of plant ash extract per hour.

ISSN:0010-3624    

DOI:10.1080/00103627009366259

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Squash (Cucurbita pepo), cucumber (Cucranis sativus), and sweet melon (Cucumis dudain) were grown in sand cultures with N supply concentrations as the variable. For several reasons, total‐N values were found to be less satisfactory than NO ‐N for the purpose of determining the critical nitrogen concentration for maximum growth. Concentrations of total‐N in mature petioles were higher in plants severely deficient in N than in less deficient plants, characteristic of a Piper‐Steenbjerg effect.

ISSN:0010-3624    

DOI:10.1080/00103627009366260

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

A correction is proposed for the evaluation of salinity effects on the basis of the electrical conductivity of saturated paste extracts. It is suggested that the dilution of the soil solution during the preparation of the saturated paste must be taken into account. Equations for estimating the electrical conductivity of a soil solution at field capacity are presented. The corrected equations improve the ability to predict the salinity hazard by determining the electrical conductivity of saturated paste extract.

ISSN:0010-3624    

DOI:10.1080/00103627009366261

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Amorphous clay separated from pedons of a highly weathered soil previously classified as Oxisol and an Ultisol of the Southern States and, from the surface horizons of an Oxisol and two Andepts of the tropics were studied by chemical, DTA, infrared and X‐ray analysis.

ISSN:0010-3624    

DOI:10.1080/00103627009366262

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103627009366256

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor