摘要:

Potassium chloride was added at various rates to the surface of soil in columns in the laboratory. The soil used was representative of some of the coconut growing areas of Papua and contained a high level of exchangeable magnesium.

ISSN:0010-3624    

DOI:10.1080/00103627909367002

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Growth regulators, pesticides, herbicides and macroelements applied to tree trunks are often translocated to the foliage. The feasibility of using bark dressings for supplying micronutrients to deficient trees was investigated using new laboratory screening methods and a field trial. Zinc was chosen as a model compound since soil and foliar applications of zinc to apple trees have not proven entirely satisfactory.

ISSN:0010-3624    

DOI:10.1080/00103627909367003

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Ammonium, nitrite, and nitrate nitrogen levels in the root zone of blight‐affected and healthy trees in a 35‐year‐old commercial orange grove were monitored at 30‐day intervals for 2 years. There was essentially no difference in NH4‐N and NO2‐N; however, at four sampling dates and overall, the NO3‐N level was slightly higher under healthy trees.

ISSN:0010-3624    

DOI:10.1080/00103627909367004

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Experiments were conducted to assess the potential influence of a commercial product, EXTEND, on nitrogen transformations and movement in a sandy soil. Neither nitrapyrin (a commercially‐available nitrification inhibitor) nor EXTEND significantly affected the rate of NH4+‐N or NO3‐‐N movement through a column of soil treated with urea‐ammonium nitrate liquid fertilizer. Nitrapyrin effectively inhibited nitrification, but the nitrification rate in the EXTEND treated systems were the same as control.

ISSN:0010-3624    

DOI:10.1080/00103627909367005

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Leaf samples were collected from upper and lower crown positions at three times during the 1971 and 1972 growing seasons for planted black walnut (Juglans nigraL.) trees on the Kaskaskia Experimental Forest in Hardin County, Illinois. The average dry weight of leaves was affected by crown position and time of year. Foliar concentrations of N, P, K, Ca, and Mg were affected by season, but not by crown position. The content of all elements tested and the concentrations of Ca and Mg increased with season while concentrations of N, P, and K decreased as the season progressed. Suggestions for sampling dates are given.

ISSN:0010-3624    

DOI:10.1080/00103627909367006

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Absorption and accumulation of calcium in hydro— ponic solutions, deficient or not in calcium, are studied on whole plants of Sorghum (Sorghum dochna F.), In deficient lots, calcium is replaced either by magnesium (Ca/Mg lot), or by potassium (Ca/K lot). The limit threshold of defiency retained, does not modify, on the 26 day of culture (end of the experience) the yield of different lots compared with the control. The principal modifications in cation content are noted in leaves: plants grown in the Ca/Mg solution show a higher Ca content than plants in a Ca/K solution. As a consequence of saturation with potassium the substitution of Ca in the two deficient lots is effected by magnesium.

ISSN:0010-3624    

DOI:10.1080/00103627909367007

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The interactions of major cations (K,Ca,Mg) are studied in Sorghum (Sorghum dochna F.); the nutritive solutions are deficient or not, in magnesium. The mineral contents of the plants grown on the reference solution are compared to those of two solutions, in which magnesium is replaced by calcium or potassium. The limit threshold of deficiency does not affect the yield of plants, but reduces strongly the content of magnesium. On the other hand, no variation of calcium is observed since the magnesium substitution is effected by potassium. The experiments do not clearly show a Mg/Ca interaction in Sorghum.

ISSN:0010-3624    

DOI:10.1080/00103627909367008

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The study of the influence of deficient dose of potassium on the mineral nutrition of sorghum (Sorghum dochna, F.) does not any modification in calcium distribution. On the other hand, the quantity and percentage of magnesium increase proportionally with the decrease of potassium. The quantity of magnesium doubles in the deficient lots compared with the reference solution. This observation shows a strong interaction between potassium and magnesium, and a much weaker one between potassium and calcium.

ISSN:0010-3624    

DOI:10.1080/00103627909367009

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103627909367001

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor