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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Retention, hydrolysis and plant availability of pyrophosphate applied to organic soil material

Parent, Léon-Etienne. January 1984 (has links)
No description available.
222

Response of wheat to nitrogenous fertilizers in the low rainfall areas of Kansas

Bieberly, Frank Gearhart. January 1949 (has links)
Call number: LD2668 .T4 1949 B51 / Master of Science
223

Effect of drying upon availability of potassium in Parsons silt loam

Scott, Thomas Walter. January 1956 (has links)
Call number: LD2668 .T4 1956 S42 / Master of Science
224

Economics of fertilizer use on wheat production

Kibria, Quazi Golam. January 1958 (has links)
Call number: LD2668 .T4 1958 K46 / Master of Science
225

Relationships of inorganic nitrogen measurements to the presence of fertilizer nitrogen in soils

Goube, Moussa Gaoh. January 1979 (has links)
Call number: LD2668 .T4 1979 G68 / Master of Science
226

Nitrogen fertilization of Pinus sylvestris seedlings

Aldridge, E. Gray. January 1986 (has links)
Call number: LD2668 .T4 1986 A42 / Master of Science
227

Response of cotton to N and water applied via a trickle irrigation system : growth, yield, and nutrient uptake

Mohamed, Abdellatif Abdellatif,1956- January 1987 (has links)
The crop growth rate (CGR); the relative growth rate (RGR); seed yield; plant uptake of N, P, K, Ca, Mg, Fe, and Na; and the water use efficiency (WUE) were studied in relation to N fertilizer and water application rate interactions in trickle-irrigated cotton. Increasing water application rate significantly increased CGR, but no significant differences were detected among the RGR values at the various water levels. Nitrogen fertilizer additions significantly increased the CGR. Nitrogen and water applications significantly increased seed yield, however, the effect of the interaction between N and water was not significant. Water levels had a positive significant effect on the cotton reproductive growth. Increased N and water significantly increased total N-uptake by cotton plants. Nitrogen additions significantly increased N% of leaves, burrs and seed. However, N% of stem was significantly reduced with high N applications. Total uptake of P, K, Ca, and Mg significantly increased with the increased application of N and water. Addition of 1.2 consumptive use (Cu) irrigation rate significantly increased P% in cotton stems, however, K% in stem was reduced. The irrigation rate of 0.9 CU and 1.2 CU significantly increased Mg% in both leaves and stems. Nitrogen application rates of 224 and 336 kg N/ha significantly decreased Mg% in leaves and stems. Increasing the irrigation rate from 0.9 CU to 1.2(1.3) CU reduced the WUE by cotton plants. However, WUE appeared to increase as N fertilizer increased up to 33 kg N/ha with water level of 0.9 CU.
228

Effect of nitrogen and phosphorus status of seed on seedling traits of winter wheat (Triticum aestivum L.)

Torres Romero, Jose Luis January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
229

Polyphosphates and microbial uptake of phosphorus : studies with soil and solution culture

Fleming, Nigel Kevin. January 1992 (has links) (PDF)
Includes bibliographical references
230

Soil and water interactions controlling wheat crop response to phosphorus fertiliser in north-western New South Wales

Norrish, Shane A, University of Western Sydney, College of Science, Technology and Environment, School of Environment and Agriculture January 2003 (has links)
This thesis examines the response to P fertiliser by wheat crops growing in the vertosol soils of the low rainfall areas of the northern grain zone of eastern Australia. Farmers in this region depend on water accumulated from rainfall over a fallow period and stored in the subsoil to increase wheat grain yield beyond that normally achievable from in-crop rainfall and to decrease the production risks due to rainfall variability. The large variability in stored water, seasonal rainfall and subsoil properties result in extremely varied yield and yield responses to P fertiliser between seasons and between sites. Finally, as a practical guide to predicting wheat response to P fertilizer: 1/. current sampling strategies of determining P only in the surface 10 cm appear to be adequate for soils with bicarbonate P concentrations greater than 15 mg/kg. 2/. For soils with lower concentrations in the surface, sampling of 80 cm is recommended. Crops with a mean concentration of bicarbonate P greater than 7 mg/kg between 10 - 80 cm are unlikely to respond to P fertiliser. 3/. No increase in profitable grain yield response was found for fertiliser applications greater than 10 kg P/ha. / Doctor of Philosophy (PhD)

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