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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.
21

Micronutrient nutrition of maize (Zea mays L.) as influenced by fertilizers, hybrids, irrigation and plant population density

Polius, J. J. N. January 1987 (has links)
No description available.
22

The effect of time and rate of nitrogen fertilization of corn on the nitrogen balance in some Quebec soils.

Sadler, John M. January 1967 (has links)
No description available.
23

Chemical behavior of phosphorus over time in fertilized soils

Zhang, Tiequan. January 1996 (has links)
Fertilizer P accumulates in soils, with potential for movement to waterways, causing eutrophication. Fertilizer P reactions in monoculture corn (Zea mays L.) production over time will determine environmentally sound soil management practices. Soil P changes over time were determined on a Chicot sandy clay loam (Grey Brown Luvisol) and a Ste. Rosalie clay (Humic Gleysol). Fertilizer P was added at 44 and 132 kg P ha$ sp{-1}$ and to the Chicot soil only, manure containing 60 kg P for the first five years. Mehlich-3 (M3) extraction, soil P fractionation, $ sp{31}$P NMR analysis, P in leaching water, and path analysis were measured. Added P increased M3 P more when manure was also added, and in clay soils. To increase M3 P by 1 kg ha$ sp{-1}$ required from 3.6 to 8.1 kg ha$ sp{-1}$ fertilizer P, and when "net" fertilizer additions were used, fertilizer required was from 1.8 to 5.3 kg P ha$ sp{-1}.$ Moderately labile organic P (Po) decreased at 0 added P. With P at the rate of plant removal, inorganic (Pi) and Po fractions were unchanged. Excess P increased labile P and resistant P through moderately labile Pi. More P remained in labile Pi fractions when manure P was added, or in the soil with the higher clay content. Soil organic P levels increased upon fertilization only in the sandy loam soil. Labile and moderately labile Po could be estimated using monoester phosphate values determined by $ sp{31}$P NMR. Inorganic P values in gravitational water increased above 0.05 mg P L$ sp{-1}$ when soil labile Pi increased above 108 mg kg$ sp{-1}$ in the sandy loam soil and 69 mg L$ sp{-1}$ in the clay soil. Thus soil P movement was related to inorganic P additions. Increased fertilizer P did not increase organic P leaching losses. Fertilizer P in corn production may result in groundwater eutrophication.
24

Comparative evaluation of some diagnostic techniques for determining the nutrient requirement of maize grown on hydric dystrandepts / Nutrient requirement of maize

Escaño, Crisanto R January 1980 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1980. / Bibliography: leaves [207]-216. / Microfiche. / xvi, 216 leaves, bound ill. 28 cm
25

Land management effects on the chemical composition of corn grown on sludge-amended soil.

Evanylo, Gregory Kevin 01 January 1978 (has links) (PDF)
No description available.
26

Micronutrient nutrition of maize (Zea mays L.) as influenced by fertilizers, hybrids, irrigation and plant population density

Polius, J. J. N. January 1987 (has links)
No description available.
27

The effect of time and rate of nitrogen fertilization of corn on the nitrogen balance in some Quebec soils.

Sadler, John M. January 1967 (has links)
No description available.
28

Corn (Zea mays L.) yield and water use as influenced by irrigation level, nitrogen fertilization, and plant population

Ba Kufimfutu, Bakelana January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
29

The effect of foliar nitrogen fertilization on nitrogen distribution, yield and protein quality of forage corn /

Ippersiel, Denis January 1986 (has links)
No description available.
30

Urea and acidic phosphate interactions in fertilizer microsites and their effect on corn (Zea mays L.) yield and nutrient use efficiency

Fan, Mingxiang January 1993 (has links)
Fertilizer applications of urea and triple superphosphate (TSP) suffer from low efficiency for corn production. Band or broadcast application of urea with acidic-P fertilizers may increase fertilizer efficiency. Urea and acidic-P fertilizer interactions in soil-fertilizer microsites were investigated using two Quebec soils. Adding acidic phosphates such as TSP and monoammonium phosphate (MAP) to urea reduced pH in microsites, urea hydrolysis, NH$ sb3$ volatilization, and increased soil NH$ sb4$- and NO$ sb3$-N contents. Ammonia loss decreased as P$ rm sb2O sb5$: urea-N ratios increased. Adding urea to P fertilizer increased soil pH and P sorption when using CaCl$ sb2$ as the electrolyte. Urea application increased 0.5 M NaHCO$ sb3$ extractable P. Banding urea with TSP caused dissolution of organic matter in soils, and increased P diffusion and P concentration in soil solution sampled with filter paper or in 1 M KCl extraction. Two years of field experiments demonstrated that banding urea with TSP or MAP increased soil extractable P (Mehlich-3), N and P nutrient uptake, plant growth and development of corn. Greater P fertilizer efficiencies and higher yields were achieved by banding urea-acidic P fertilizers.

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