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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.
11

Mapping zinc fertility of soils using indicator plants and soil analyses

Rashid, Abdul January 1986 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1986. / Bibliography: leaves 325-340. / Photocopy. / Microfiche. / xxviii, 340 leaves, bound ill., maps 29 cm
12

Responses of chickpea (Cicer arietinum L.) to zinc supply and water deficits / by Habib Ur Rahman Khan.

Khan, Habib Ur Rahman January 1998 (has links)
Bibliography: leaves 201-228. / xvii, 228 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Widespread deficiencies of mineral nutrients in soils along with limited moisture supply are considered major environmental stresses leading to yield losses in chickpea. This study was conducted to determine the zinc requirement of chickpea and the effect on plant water relations. Critical zinc concentration was estimated. It was found that high and low moisture regimes had no effect on critical zinc concentration and that the value remained almost the same in all chickpea genotypes. Sensitivity of 28 chickpea genotypes were evaluated at two zinc levels. Field studies on zinc fertilization in both Australia and Pakistan showed that the application of zinc increased grain yield in all chickpea genotypes. It was found that plants grown under zinc deficiency could not exploit available soil moisture and water use and water use efficiency was reduced, and concluded that high zinc availability may enhance the ability of plants to endure periods of drought by promoting osmotic adjustment. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1999
13

Responses of chickpea (Cicer arietinum L.) to zinc supply and water deficits / by Habib Ur Rahman Khan.

Khan, Habib Ur Rahman January 1998 (has links)
Bibliography: leaves 201-228. / xvii, 228 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Widespread deficiencies of mineral nutrients in soils along with limited moisture supply are considered major environmental stresses leading to yield losses in chickpea. This study was conducted to determine the zinc requirement of chickpea and the effect on plant water relations. Critical zinc concentration was estimated. It was found that high and low moisture regimes had no effect on critical zinc concentration and that the value remained almost the same in all chickpea genotypes. Sensitivity of 28 chickpea genotypes were evaluated at two zinc levels. Field studies on zinc fertilization in both Australia and Pakistan showed that the application of zinc increased grain yield in all chickpea genotypes. It was found that plants grown under zinc deficiency could not exploit available soil moisture and water use and water use efficiency was reduced, and concluded that high zinc availability may enhance the ability of plants to endure periods of drought by promoting osmotic adjustment. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1999
14

Crescimento e acúmulo de nutrientes em porta-enxertos de caramboleira adubados com zinco

Lima Neto, Antonio João de [UNESP] 06 February 2014 (has links) (PDF)
Made available in DSpace on 2014-11-10T11:09:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-06Bitstream added on 2014-11-10T11:58:11Z : No. of bitstreams: 1 000795069.pdf: 861949 bytes, checksum: 6bb340e04b3b554470b80d7531fad4a7 (MD5) / O Brasil está entre os maiores produtores mundiais de carambola, sendo o estado de São Paulo responsável pela maior parte da produção nacional. Apesar da importância da cultura, ainda são escassas na literatura informações sobre adubação, principalmente quanto ao uso de micronutrientes na produção de porta-enxertos. Diante da falta de informações, o trabalho objetivou avaliar a influência do zinco sobre o crescimento, composição mineral e eficiência nutricional de porta-enxertos de caramboleira. O trabalho foi desenvolvido entre os meses de setembro de 2012 e fevereiro de 2013, em um viveiro comercial de produção de mudas, localizado em Taquaritinga, SP. O delineamento utilizado foi em blocos casualizados, com cinco doses de zinco: D0 = zero de Zn; D1 = 2; D2 = 4; D3 = 6; e, D4 = 8 mg de Zn dm-3, quatro repetições e três plantas por parcela. Aos 170 dias após a aplicação do zinco avaliou-se: altura das plantas, diâmetro do caule e número de folhas. Em seguida, as plantas foram coletadas, separadas em parte aérea e raízes, secas, pesadas, moídas e determinados os teores, calculados os acúmulos, a eficiência de absorção, de transporte e de utilização de macro e micronutrientes. Todos os parâmetros de crescimento avaliados, responderam à aplicação das doses de zinco. O acúmulo de Zn, P, K, Mg e S na planta, também responderam à aplicação de zinco. As doses mais elevadas de zinco aumentaram a eficiência de absorção de Zn e, reduziram o transporte de Ca e Mn. Pelos resultados, conclui-se que, o maior desenvolvimento dos porta-enxertos de caramboleira esteve associado à dose entre 3,1 e 3,8 mg de Zn dm-3. Doses elevadas de zinco promovem menor teor, acúmulo e eficiência de utilização para a maioria dos macro e micronutrientes / Brazil is among the world's largest producers of starfruit, with the state of São Paulo accounting for most of the national production. Despite the importance of this culture, information about the fertilization of this culture is scarce in literature, particularly regarding the use of micronutrients in producing rootstocks. Due to lack of information, this study aimed to evaluate the influence zinc has on growth, mineral composition and nutritional efficiency of star fruit rootstocks. The study was conducted between the months of September 2012 and February 2013 in a seedling production nursery located in Taquaritinga, SP. A randomized block design with five doses of zinc was used to carry out the study with four replications and three plants per plot: D0 = zero, D1 = 2, D2 = 4, D3 = 6, and D4 = 8 mg Zn dm-3. At 170 days after applying the zinc, the plant height, stem diameter and number of leaves were analyzed. The plants were then collected and divided into shoots and roots, dried, weighed, ground and the content was evaluated. The accumulations were calculated as well as the efficiency of absorption, transport and utilization of macro and micronutrients. All growth parameters evaluated responded to the zinc doses. The accumulation of Zn, P, K, Mg and S in the plant also responded to the zinc. The higher doses of zinc increased the absorption efficiency of Zn and reduced the transport of Ca and Mn. From these results, it is concluded that largest development of starfruit rootstocks was associated with the dose between 3.1 and 3.8 mg of Zn dm-3. High doses of zinc promote lower content, accumulation and utilization efficiency for most macro and micronutrients
15

Crescimento e acúmulo de nutrientes em porta-enxertos de caramboleira adubados com zinco /

Lima Neto, Antonio João de. January 2014 (has links)
Orientador: William Natale / Banca: Antonio Baldo Geraldo Martins / Banca: Danilo Eduardo Rozane / Resumo: O Brasil está entre os maiores produtores mundiais de carambola, sendo o estado de São Paulo responsável pela maior parte da produção nacional. Apesar da importância da cultura, ainda são escassas na literatura informações sobre adubação, principalmente quanto ao uso de micronutrientes na produção de porta-enxertos. Diante da falta de informações, o trabalho objetivou avaliar a influência do zinco sobre o crescimento, composição mineral e eficiência nutricional de porta-enxertos de caramboleira. O trabalho foi desenvolvido entre os meses de setembro de 2012 e fevereiro de 2013, em um viveiro comercial de produção de mudas, localizado em Taquaritinga, SP. O delineamento utilizado foi em blocos casualizados, com cinco doses de zinco: D0 = zero de Zn; D1 = 2; D2 = 4; D3 = 6; e, D4 = 8 mg de Zn dm-3, quatro repetições e três plantas por parcela. Aos 170 dias após a aplicação do zinco avaliou-se: altura das plantas, diâmetro do caule e número de folhas. Em seguida, as plantas foram coletadas, separadas em parte aérea e raízes, secas, pesadas, moídas e determinados os teores, calculados os acúmulos, a eficiência de absorção, de transporte e de utilização de macro e micronutrientes. Todos os parâmetros de crescimento avaliados, responderam à aplicação das doses de zinco. O acúmulo de Zn, P, K, Mg e S na planta, também responderam à aplicação de zinco. As doses mais elevadas de zinco aumentaram a eficiência de absorção de Zn e, reduziram o transporte de Ca e Mn. Pelos resultados, conclui-se que, o maior desenvolvimento dos porta-enxertos de caramboleira esteve associado à dose entre 3,1 e 3,8 mg de Zn dm-3. Doses elevadas de zinco promovem menor teor, acúmulo e eficiência de utilização para a maioria dos macro e micronutrientes / Abstract: Brazil is among the world's largest producers of starfruit, with the state of São Paulo accounting for most of the national production. Despite the importance of this culture, information about the fertilization of this culture is scarce in literature, particularly regarding the use of micronutrients in producing rootstocks. Due to lack of information, this study aimed to evaluate the influence zinc has on growth, mineral composition and nutritional efficiency of star fruit rootstocks. The study was conducted between the months of September 2012 and February 2013 in a seedling production nursery located in Taquaritinga, SP. A randomized block design with five doses of zinc was used to carry out the study with four replications and three plants per plot: D0 = zero, D1 = 2, D2 = 4, D3 = 6, and D4 = 8 mg Zn dm-3. At 170 days after applying the zinc, the plant height, stem diameter and number of leaves were analyzed. The plants were then collected and divided into shoots and roots, dried, weighed, ground and the content was evaluated. The accumulations were calculated as well as the efficiency of absorption, transport and utilization of macro and micronutrients. All growth parameters evaluated responded to the zinc doses. The accumulation of Zn, P, K, Mg and S in the plant also responded to the zinc. The higher doses of zinc increased the absorption efficiency of Zn and reduced the transport of Ca and Mn. From these results, it is concluded that largest development of starfruit rootstocks was associated with the dose between 3.1 and 3.8 mg of Zn dm-3. High doses of zinc promote lower content, accumulation and utilization efficiency for most macro and micronutrients / Mestre
16

The combined effect of Cu and Zn on Selenastrum capricornutum

Colonia-Roque, Helmer 01 January 1983 (has links)
It has been demonstrated that the toxicity of heavy metals depends on their chemical speciation and can be related to their free ion activities, rather than the total metal concentrations (Steemann- Nielsen and Wium-Andersen, 1970; Sunda and Guillard, 1976; Andrew, Biesinger, and Glass, 1977; Anderson, Morel and Guillard, 1978). The objective of this study was to determine the effect of combined free ions of zinc and copper on the toxicity to the green alga Selenastrum capricornutum. This alga was grown in a defined medium, under controlled laboratory conditions, with a varying range of zinc and copper concentrations. The growth rate of the alga was inhibited at pZn = 5.93 or at pCu = 7.24. The results suggest that when the chemical speciation of combined zinc and copper is taken into account, there is little or no toxic interaction between the two metal ions.
17

Characterization and plant availability of zinc in British Columbia orchard soils

Neilsen, Denise. January 1986 (has links)
No description available.
18

Response of corn to high levels of CuSO₄ and ZnSO₄ applications

Winarko, Clementinus 14 November 2012 (has links)
Copper and Zn deficiencies of crop plants occur in various areas throughout the world. The sulfate forms of Cu and Zn are generally used to correct these micronutrient deficiencies. In agricultural practices, Cu and Zn are applied to soils not only as a fertilizer but also as manures, pesticides and waste materials such as sewage sludge. High levels of Cu and Zn application to agricultural soils are considered to pose a potential hazard to plants and animals. Research findings have not established Cu and Zn levels that either injure plants or increase Cu and Zn concentrations in edible plant portions to undesirably high levels. Published data on the fate of applied Cu and Zn indicate that there is little, if any, downward movement of these micronutrients in soils and that, with time, applied Cu and Zn revert to plant unavailable forms in soils. / Master of Science
19

Zinc as a subsoil nutrient for cereals

Holloway, R. E. (Robert Edgcumbe) January 1996 (has links) (PDF)
Bibliography: leaves 290-324. This thesis investigates two avenues suggested by Graham and Ascher (1993) for approaching the problems of subsoil infertility, with particular reference to zinc. Field experiments with wheat and barley were established at Minnipa, on Eyre Peninsula in South Australia to investigate the effects of applying nutrients (principally zinc, nitrogen and phosphorus) to the subsoil to a depth of 0.4 m with a modified deep ripper. A deep pot experiment was designed to measure the zinc efficiencies (in terms of dry matter production) of a range of species grown in siliceous sand. The effects of added zinc on root growth were compared. A pot experiment was also designed to measure the effects of zinc placement in the soil on the zinc concentrations and uptake in Excalibur, particularly with respect to concentrations in grain.
20

Zinc as a subsoil nutrient for cereals / by R.E. Holloway.

Holloway, R. E. (Robert Edgcumbe) January 1996 (has links)
Bibliography: leaves 290-324. / xxii, 324 leaves, [5] leaves of plates : col. ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis investigates two avenues suggested by Graham and Ascher (1993) for approaching the problems of subsoil infertility, with particular reference to zinc. Field experiments with wheat and barley were established at Minnipa, on Eyre Peninsula in South Australia to investigate the effects of applying nutrients (principally zinc, nitrogen and phosphorus) to the subsoil to a depth of 0.4 m with a modified deep ripper. A deep pot experiment was designed to measure the zinc efficiencies (in terms of dry matter production) of a range of species grown in siliceous sand. The effects of added zinc on root growth were compared. A pot experiment was also designed to measure the effects of zinc placement in the soil on the zinc concentrations and uptake in Excalibur, particularly with respect to concentrations in grain. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agronomy and Farming Systems, 1997

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