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Macrofauna do solo influenciada pelo uso de fertilizantes químicos e dejetos de suínos no oeste do estado de Santa Catarina; Soil macrofauna as influenced by chemical fertilizers and swine manure use in western Santa Catarina State, Brazil

ALVES, Maurício Vicente; SANTOS, Júlio Cesar Pires; GOIS, Deisi Tatiani de; ALBERTON, Janaina Veronezi; BARETTA, Dilmar
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
46.19%
Este estudo objetivou avaliar o efeito da adição de doses crescentes de dejetos de suínos, adubação organomineral e adubação mineral sobre a abundância e diversidade da macrofauna edáfica. O estudo foi realizado no município de Campos Novos, SC, em um Latossolo Vermelho distroférrico, cultivado anualmente com milho (Zea mays) e aveia (Avena sativa), em sucessão e semeadura direta. Os seis tratamentos utilizados foram: testemunha (TT); adubação mineral (AM); adubação organomineral (AOM); adubação orgânica na doses de 3 t ha-1 (AO3); 6 t ha-1 (AO6) e 12 t ha-1 (AO12) de dejeto de suínos em base seca. O fertilizante mineral foi aplicado em semeadura na linha do plantio e a adubação orgânica, após semeadura do milho. A macrofauna edáfica foi avaliada utilizando-se um amostrador cilíndrico com 17 cm de diâmetro, coletando-se amostras de solo na profundidade de 0-10 cm. As amostragens foram realizadas em três épocas: a primeira em 5/5/2005 (um mês após a colheita do milho), a segunda em 9/09/2005 (sob a cultura de aveia), e a terceira em 23/1/2006 (sob a cultura do milho). A diversidade de organismos foi avaliada por meio dos índices de Shannon, Simpson e Pielou, riqueza de grupos, abundância e análise de agrupamento. A freqüência relativa das ordens foi afetada pela adição do dejeto suíno...

Fertilizers applied to certified organic tomato culture

MARTINS, T. C. G.; FERNANDES, E. A. De Nadai; FERRARI, A. A.; BACCHI, M. A.; TAGLIAFERRO, F. S.
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.51%
The tomato culture demands large quantities of mineral nutrients, which are supplied by synthetic fertilizers in the conventional cultivation system. In the organic cultivation system only alternative fertilizers are allowed by the certifiers and accepted as safe for humans and environment. The chemical composition of rice bran, oyster flour, cattle manure and ground charcoal, as well as soils and tomato fruits were evaluated by instrumental neutron activation analysis (INAA). The potential contribution of organic fertilizers to the enrichment of chemical elements in soil and their transfer to fruits was investigated using concentration ratios for fertilizer and soil samples, and also for soil and tomato. Results evidenced that these alternative fertilizers could be taken as important sources of Br, Ca, Ce, K, Na and Zn for the organic tomato culture.

Avaliação e caracterização da disponibilidade do boro e zinco contidos em fertilizantes.; Evaluation and characterization of boron and zinc availability from fertilizers.

Vale, Fábio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/05/2001 PT
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36.39%
A legislação brasileira de fertilizantes define que os micronutrientes sejam garantidos pelo seu total presente. Isto permite a utilização de produtos não considerados como fontes de micronutrientes na fabricação dos fertilizantes, como, por exemplo, subprodutos industriais, porém com eficiência agronômica ainda não devidamente comprovada. O objetivo deste trabalho foi caracterizar a solubilidade do boro e do zinco contidos em fertilizantes, utilizando extratores químicos, e correlacionar com a disponibilidade desses elementos para plantas, procurando identificar o extrator que melhor avalie essa disponibilidade. A disponibilidade do boro avaliada por plantas testes de soja, foi a mesma em todos os produtos. Os resultados mostraram que tanto a garantia pelo teor total quanto pelo teor solúvel em soluções de ácido cítrico 20 g L-1 ou de citrato neutro de amônio (1+9), foram bons para indicar a disponibilidade deste micronutriente em todos os fertilizantes. O extrator citrato neutro de amônio (1+9), na relação 1:100 e com fervura por cinco minutos, apresentou uma satisfatória correlação com a absorção pelas plantas. Sua adoção contribuirá para o aumento da eficiência das adubações com zinco e também fortalecer a idoneidade de setor de fertilizantes...

Dessecação de plantas daninhas com o herbicida glyphosate associado a fertilizantes nitrogenados; Weed desiccation with the herbicide glyphosate associated to nitrogen fertilizers

Carvalho, Saul Jorge Pinto de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 04/12/2009 PT
Relevância na Pesquisa
36.39%
A expansão dos sistemas conservacionistas de manejo do solo e das culturas geneticamente modificadas para tolerância a herbicidas contribuiu sobremaneira para a crescente adoção do herbicida glyphosate que, atualmente, pode ser considerado o herbicida de maior importância mundial. Na tentativa de elevar a eficácia deste herbicida, diversas substâncias têm sido adicionadas à calda de pulverização, dentre elas a uréia e o sulfato de amônio. Neste sentido, este trabalho foi desenvolvido com o objetivo de avaliar aspectos da dessecação da cobertura vegetal com o herbicida glyphosate quando influenciada pela adição de uréia e/ou sulfato de amônio à calda de pulverização, incluindo a análise de doses, alterações no pH da calda, participação fisiológica do nitrogênio, aplicação conjunta dos fertilizantes e controle de diferentes espécies vegetais. Para tanto, nove experimentos foram desenvolvidos em campo, em áreas da Escola Superior de Agricultura Luiz de Queiroz Esalq/USP, em Piracicaba SP. Em complementação, cinco experimentos foram desenvolvidos em casa-de-vegetação e outros quatro experimentos foram desenvolvidos no Laboratório de Biologia de Plantas Daninhas, ambos do Departamento de Produção Vegetal...

Contribuição ao banco de dados brasileiro para apoio à avaliação do ciclo de vida: fertilizantes nitrogenados.; Contribution for the Brazilian database to support life cycle assessment: nitrogen fertilizers.

Ribeiro, Paulo Henrique
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 11/09/2009 PT
Relevância na Pesquisa
46.34%
A principal limitação da Avaliação do Ciclo de Vida (ACV) é a necessidade da coleta de um elevado número de dados representativos para a região em estudo. Esta limitação pode ser contornada pela construção de bancos de dados regionais, ou seja, de inventários de elementos que são comuns aos ciclos de vida de inúmeros produtos. Entre esses elementos encontram-se os fertilizantes químicos. Nesse contexto este trabalho de doutorado apresenta uma contribuição ao banco de dados brasileiro para apoio aos estudos de ACV, qual seja: os inventários do ciclo de vida da uréia; do nitrato de amônio e do sulfato de amônio adequados às condições brasileiras. Para a elaboração dos inventários foi necessário obter o perfil detalhado do setor de fertilizantes nitrogenados no país. Em seguida, efetuou-se a identificação e quantificação das entradas de recursos naturais e das disposições de rejeitos associados ao ciclo de vida dos fertilizantes estudados. Por fim, fez-se uma discussão dos principais aspectos ambientais associados à produção dos três fertilizantes no Brasil. Os dados obtidos no inventário da uréia revelaram 45 aspectos ambientais. No que diz respeito às emissões atmosféricas, verificou-se que o dióxido de carbono foi responsável por 98...

Distribuição elementar e de radionuclídeos na produção e uso de fertilizantes fosfatados no Brasil; Elemental and radionuclides distribution in the production and use of phosphate fertilizers in Brazil

Saueia, Cátia Heloisa Rosignoli
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/09/2006 PT
Relevância na Pesquisa
36.51%
O fertilizante é considerado um componente essencial para a agricultura, pois sua utilização aumenta e repõe os nutrientes naturais do solo, perdidos por desgaste ou erosão. No processo de obtenção dos fertilizantes fosfatados, o concentrado de rocha reage com ácido sulfúrico concentrado produzindo ácido fosfórico e sulfato de cálcio (fosfogesso), como subproduto. O ácido fosfórico é utilizado para a produção do superfosfato triplo (TSP), superfosfato simples (SSP), monoamônio fosfato (MAP) e diamônio fosfato (DAP). A rocha fosfatada usada como matéria prima apresenta em sua composição radionuclídeos das séries naturais do urânio e tório. Durante o ataque químico do concentrado de rocha, as espécies presentes na reação, estáveis e radioativas, são redistribuídas entre o ácido fosfórico (matéria prima dos fertilizantes), e o fosfogesso, de acordo com sua solubilidade e características químicas. Enquanto os fertilizantes são comercializados, o fosfogesso fica estocado em pilhas podendo impactar o meio ambiente. Com a finalidade de entender a distribuição dos elementos e dos radionuclídeos no processo industrial de produção de fertilizantes fosfatados, foram analisadas amostras de concentrado de rocha...

Estudo de alguns fatores que podem afetar a durabilidade de misturas solo-cal; Study of some factors that may affect durability of soil-lime mixtures

Bueno, Eduardo Suliman
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
46.51%
O desenvolvimento sustentável impõe uma evolução do contexto sócio-econômico das obras que envolvem o uso do solo. Um efeito é a obrigação do uso de materiais localizados na obra ou nas imediações. Isto muitas vezes implica no uso de materiais de baixas propriedades de engenharia, surgem então alternativas de melhoria destes materiais, como a estabilização com cal. No entanto, sabe-se que o tratamento de solos pode ser ineficaz quando da presença de compostos químicos deletérios no solo. Esta dissertação apresenta resultados de um estudo laboratorial do comportamento mecânico de um solo laterítico estabilizado com cal cálcica e com cal dolomítica. Para avaliar a influência de agentes químicos, foram usados quatro tipos de fertilizantes químicos de uso comum na agricultura. O estudo incluiu a caracterização do solo, ensaios de compactação, difratometria de Raios-X e compressão simples do solo e das misturas solo-cal e solo-cal contaminado com fertilizante. Foram adotados teores de 1% de fertilizante e 4% de cal, os tempos de cura foram de 7, 14, 28, 56, 112 e 140 dias sob duas condições: cura em câmara sem controle de umidade e cura em câmara úmida a fim de avaliar a influência da perda de umidade sobre o ganho de resistência. Os resultados demonstraram que a adição de fertilizantes químicos diminuiu o ganho de resistência em até 13% em misturas com fertilizantes nitrogenados e cal dolomítica e até 36% em misturas com fertilizantes não-nitrogenados e cal cálcica. O ganho de resistência com cal cálcica foi o dobro do ganho com cal dolomítica...

The use of rocks to improve family agriculture in Brazil

Theodoro, Suzi Maria de Cordova Huff; Leonardos, Othon Henry
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.28%
ABSTRACT: During the second half of the 20th century, the introduction of new chemical agriculture technologies brought about a revolution in food production, but this has also cause deep deterioration in our relationships with the natural environment. In developing tropical countries, record yields were accompanied by rural exodus, widespread deforestation and loss of topsoil. The stonemeal research described herein is an alternative to such practices as it is an environmental friendly and socially responsible technology based on soil rejuvenation and conservation by means of the addition of natural rock powders that are rich in phosphorous, calcium, magnesium, potassium and micronutrients. The research adopted an inter-disciplinary approach and was conducted among small farmers of a rural community located in the state of Minas Gerais, Brazil. The major goal was to demonstrate that there is a harmless cheap and simple alternative to fertilizing degraded or impoverished soils, which allow farmers to sustain high productivity and to remain on their plots of land. Results have confirmed the economic, environmental and productive feasibility and advantage of the stonemeal technique for corn, rise, manioc, sugar cane and horticultural species...

THE EFFECT OF THE PHYSICAL PROPERTIES OF PARTICLES OF BULK-BLENDED FERTILIZERS ON SEGREGATION BY CONING

Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/1997 EN
Relevância na Pesquisa
46.19%
Bulk blending is a way to produce compound fertilizers in which the different nutrients are present in different particles. Due to the heterogeneous composition of bulk blends, particle segregation, when it occurs, is a serious problem to the fertilizer producer, as well as to the farmer. Free fall is one of the main types of particle movement to promote segregation. The physical properties of the particles that potentially affect the tendency to segregate the most are size, density and shape. The main objective of this work is to study the influence of size and density of particles and distance of fall on segregation due to free fall. It was found that particle size is the most important physical characteristic to affect segregation; the greater the difference in particle size, the greater the segregation. Free fall is an important mechanical factor affecting segregation; the greater the distance of fall, the greater the segregation. No evidence of the influence of particle density on segregation was found

Investigation the natural radioactivity in local and imported chemical fertilizers

Hussain,Raad Obid; Hussain,Hayder Hamza
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 EN
Relevância na Pesquisa
46.26%
In order to assess the radioactive level in the environment, the specific activities of 238U, 232Th and 40K were measured by using a gamma ray spectrometer based on a NaI(Tl) detector. The results showed that the specific activities of 238U, 232Th and 40K were 12.846-88.585, 1.304-26.656 and 11.598-2275.896 Bq/kg respectively. The radium equivalent activity was also calculated which varied from 0.893 to 175.244 Bq/kg. The radium equivalent average values were lower than the world average. In general, the highest level of radium equivalent value was in leafy type NPK fertilizers. The urea type had no radionuclide. The specific activity and absorbed dose rate at 1m above the ground surface (nGy/h) after NPK fertilizers agricultural applications were calculated and the maximum value of dose rate was 0.15% of the world average outdoor exposure due to terrestrial gamma radiation.

Bacteria in combination with fertilizers promote root and shoot growth of maize in saline-sodic soil

Zafar-ul-Hye,Muhammad; Farooq,Hafiz Muhammad; Hussain,Mubshar
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2015 EN
Relevância na Pesquisa
36.41%
Salinity is the leading abiotic stress hampering maize (Zea mays L.) growth throughout the world, especially in Pakistan. During salinity stress, the endogenous ethylene level in plants increases, which retards proper root growth and consequent shoot growth of the plants. However, certain bacteria contain the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which converts 1-aminocyclopropane-1-carboxylic acid (an immediate precursor of ethylene biosynthesis in higher plants) into ammonia and α-ketobutyrate instead of ethylene. In the present study, two Pseudomonas bacterial strains containing ACC-deaminase were tested separately and in combinations with mineral fertilizers to determine their potential to minimize/undo the effects of salinity on maize plants grown under saline-sodic field conditions. The data recorded at 30, 50 and 70 days after sowing revealed that both the Pseudomonas bacterial strains improved root and shoot length, root and shoot fresh weight, and root and shoot dry weight up to 34, 43, 35, 71, 55 and 68%, respectively, when applied without chemical fertilizers: these parameter were enhanced up to 108, 95, 100, 131, 100 and 198%, respectively, when the strains were applied along with chemical fertilizers. It can be concluded that ACC-deaminase Pseudomonas bacterial strains applied alone and in conjunction with mineral fertilizers improved the root and shoot growth of maize seedlings grown in saline-sodic soil.

Antagonism at combined effects of chemical fertilizers and carbamate insecticides on the rice-field N2-fixing cyanobacterium Cylindrospermum sp. in vitro

Padhy, Rabindra N.; Nayak, Nabakishore; Rath, Shakti
Fonte: Slovak Toxicology Society SETOX Publicador: Slovak Toxicology Society SETOX
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.46%
Effects of chemical fertilizers (urea, super phosphate and potash) on toxicities of two carbamate insecticides, carbaryl and carbofuran, individually to the N2-fixing cyanobacterium, Cylindrospermum sp. were studied in vitro at partially lethal levels (below highest permissive concentrations) of each insecticide. The average number of vegetative cells between two polar heterocysts was 16.3 in control cultures, while the mean value of filament length increased in the presence of chemical fertilizers, individually. Urea at the 10 ppm level was growth stimulatory and at the 50 ppm level it was growth inhibitory in control cultures, while at 100 ppm it was antagonistic, i.e. toxicity-enhancing along with carbaryl, individually to the cyanobacterium, antagonism was recorded. Urea at 50 ppm had toxicity reducing effect with carbaryl or carbofuran. At 100 and 250 ppm carbofuran levels, 50 ppm urea only had a progressive growth enhancing effect, which was marked well at 250 ppm carbofuran level, a situation of synergism. Super phosphate at the 10 ppm level only was growth promoting in control cultures, but it was antagonistic at its higher levels (50 and 100 ppm) along with both insecticides, individually. Potash (100, 200, 300 and 400 ppm) reduced toxicity due to carbaryl 20 and carbofuran 250 ppm levels...

Bacteria in combination with fertilizers promote root and shoot growth of maize in saline-sodic soil

Zafar-ul-Hye, Muhammad; Farooq, Hafiz Muhammad; Hussain, Mubshar
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica
Publicado em 01/03/2015 EN
Relevância na Pesquisa
36.41%
Salinity is the leading abiotic stress hampering maize ( Zea mays L.) growth throughout the world, especially in Pakistan. During salinity stress, the endogenous ethylene level in plants increases, which retards proper root growth and consequent shoot growth of the plants. However, certain bacteria contain the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which converts 1-aminocyclopropane-1-carboxylic acid (an immediate precursor of ethylene biosynthesis in higher plants) into ammonia and α-ketobutyrate instead of ethylene. In the present study, two Pseudomonas bacterial strains containing ACC-deaminase were tested separately and in combinations with mineral fertilizers to determine their potential to minimize/undo the effects of salinity on maize plants grown under saline-sodic field conditions. The data recorded at 30, 50 and 70 days after sowing revealed that both the Pseudomonas bacterial strains improved root and shoot length, root and shoot fresh weight, and root and shoot dry weight up to 34, 43, 35, 71, 55 and 68%, respectively, when applied without chemical fertilizers: these parameter were enhanced up to 108, 95, 100, 131, 100 and 198%, respectively, when the strains were applied along with chemical fertilizers. It can be concluded that ACC-deaminase Pseudomonas bacterial strains applied alone and in conjunction with mineral fertilizers improved the root and shoot growth of maize seedlings grown in saline-sodic soil.

Chemical properties of an Oxisol under organic management as influenced by application of sugarcane bagasse ash.

FERREIRA, E. P. de B.; FAGERIA, N. K.; DIDONET, A. D.
Fonte: Revista Ciência Agronômica, Fortaleza, v. 43, n. 2, p. 228-236, abr./jun. 2012. Publicador: Revista Ciência Agronômica, Fortaleza, v. 43, n. 2, p. 228-236, abr./jun. 2012.
Tipo: Artigo em periódico indexado (ALICE)
PT_BR
Relevância na Pesquisa
46.41%
There are large areas of Oxisols in South America, including Brazil, with low fertility and acidity. To improve crop yields on these Oxisols, liming and fertilization is an essential practice. However, besides the high cost of fertilizers, chemical fertilizers cannot be used in organic production systems, except insoluble sources. Ash is one of the alternative source of supplying macro and micronutrients. A field experiment was conducted, in a completely randomized block design in a factorial arrangement (three sources of ash x four rates) resulting on 12 treatments, to evaluate the effect of source and rate of ash application on soil chemical properties. The treatments consisted of three sources (bagasse, bagasse+PJ07-A and bagasse+PJ07-RA) of sugarcane ash applied in four rates as 0; 5; 15 and 30 Mg ha-1. Results showed that the use of ash significantly improved soil chemical properties such as pH, P, K, Mg, base saturation, K and Mg saturation and significantly reduced soil acidity (H+Al). Depending on the ash source or rate, some of the soil chemical properties were affected, however, the effect of ash source was not so pronounced as compared with ash rate. Ashes application resulted on a soil nutritional condition enough to guarantee the growth and yield of most annual crops. Ash sources were equally effective in reducing acidity and improving soil fertility under this study condition...

Incomplete Markets and Fertilizer Use : Evidence from Ethiopia

Zerfu, Daniel; Larson, Donald F.
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
36.43%
While the economic returns to using chemical fertilizer in Africa can be large, application rates are low. This study explores whether this is due to missing and imperfect markets. Results based on a panel survey of Ethiopian farmers suggest that while fertilizer markets are not altogether missing in rural Ethiopia, high transport costs, unfavorable climate, price risk, and illiteracy present formidable hurdles to farmer participation. Moreover, the combination of factors that promote or impede effective fertilizer markets differs among locations, making it difficult to find a single production technology that is uniformly profitable -- perhaps explaining the inconsistency between field studies finding large returns to fertilizer use in Ethiopia and survey-based studies finding fertilizer use to be uneconomic. The results suggest that households with greater stores of wealth, human capital and authority can overcome these hurdles. The finding offers some encouragement, but also implies a self-enforcing link between low agricultural productivity and poverty...

Improving Soil Fertility Management in Sub-Saharan Africa

Donovan, Graeme; Casey, Frank
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
46.47%
There are more than 60 million smallholder farmers in Sub-Saharan Africa (SSA). Declining soil fertility is a fundamental impediment to agricultural growth and a major reason for slow growth in food production in SSA. In Africa, as a result of soil degradation, irrigated lands may be, on average, 7 percent below their potential productivity, rain-fed crop lands 14 percent below their potential and rangelands 45 percent below potential. Compared to parts of North America, Europe and of Asia, most SSA soils are naturally not very fertile. Low in a number of chemical constituents such as phosphorus, sulphur, magnesium and zinc, low amounts of soil organic matter (SOM) combined with poor land cover have resulted in poor soil structure, limited rooting depth and susceptibility to accelerated erosion. However, similar soils in other parts of the world have been made highly productive by using appropriate management techniques. There are two main approaches to improved soil fertility management. One is to attempt to meet plant requirements with purchased mineral fertilizers. The second relies on biological processes to optimize nutrient recycling...

Nutrient availability and wheat growth as affected by plant residues and inorganic fertilizers in saline soils.

Elgharably, Ahmed Galal
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2008
Relevância na Pesquisa
36.39%
Over 10% of the world’s land is salt affected. Salt accumulation is a major soil constraint for agricultural sustainability in arable or newly cultivated soils. As a result of salinity, soil chemical, physical and biological properties deteriorate, plant uptake of water and nutrients, particularly P, decreases and plant growth declines. Application of plant residues can enhance the activity of soil microorganisms, the availability of nutrients, including P and the plant uptake of P and growth. Such a practice can also be economically viable as it can reduce the use of P from inorganic sources, maintaining the world’s reserve of P rocks and reducing the price of fertilizers and the environmental pollution often associated with the excessive application of inorganic N and P fertilizers. Little is known about how P, with N in proper form, added from inorganic and/or residue sources can affect wheat growth in the salt affected soils with no confounding pH or sodium adsorption ratio (SAR). Increasing microbial activity, N and P availability and wheat uptake of P by application of N and P from organic and inorganic sources may improve wheat growth and hence productivity under saline conditions. The overall aim of this study was to determine ways for enhancing the activity of microorganisms and increasing the availability of N and P...

The development of new slow-release boron fertilizers.

Abat, Margaret
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2015
Relevância na Pesquisa
36.4%
Boron (B) deficiency and/or toxicity have caused significant impacts on agricultural crop production worldwide. The most commonly used sources of fertilizer B are water soluble, and are therefore susceptible to leaching in high rainfall environments. This may result in insufficient supply of B for plant growth later in the crop growth cycle (e.g. flowering), when B supply is most needed. Moreover, these highly soluble sources pose an increased risk of B toxicity to seedlings just after planting. One possible way to reduce nutrient losses and avoid seedling toxicity is by using slow-release fertilizer. Slow-release fertilizers provide an effective means to overcome the low use-efficiency and problems associated with highly soluble fertilizers in soils prone to nutrient leaching. This study has identified boron phosphate (BPO₄) compounds as potential raw materials for incorporation into macronutrient fertilizers to produce compound fertilizers containing slow-release B. The BPO₄ compounds were found to differ significantly from most commercially available B sources in terms of their physical and chemical characteristics. Boron phosphate compounds synthesized at 500 and 800 °C had low water solubility, with solubility decreasing with decreasing pH...

Effect of Agricultural Amendments on Cajanus cajan (Pigeon Pea) and Its Rhizospheric Microbial Communities – A Comparison between Chemical Fertilizers and Bioinoculants

Gupta, Rashi; Bisaria, V. S.; Sharma, Shilpi
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 31/07/2015 EN
Relevância na Pesquisa
46.36%
Inoculation of leguminous seeds with bioinoculants has been practiced in agriculture for decades to ameliorate grain yield by enhanced growth parameters and soil fertility. However, effective enhancement of plant growth parameters results not only from the direct effects these bioinoculants impose on them but also from their non-target effects. The ability of bioinoculants to reduce the application of chemicals for obtaining optimum yield of legume appears to be of great ecological and economic importance. In the present study, we compared the influence of seed inoculation of Cajanus cajan with a microbial consortium, comprising Bacillus megaterium, Pseudomonas fluorescens and Trichoderma harzianum, with that of application of chemical fertilizers on plant’s growth parameters and its rhizospheric microbial communities. Real-time PCR assay was carried out to target the structure (16S rRNA) and function (nitrogen cycle) of rhizospheric microbiota, using both DNA and RNA as markers. The results showed that the microbial consortium was the most efficient in increasing grain yield (2.5-fold), even better than the recommended dose of chemical fertilizers (by 1.2-fold) and showed enhancement in nifH and amoA transcripts by 2.7- and 2.0-fold...

Container Plants: A Comparison of Organic and Inorganic Fertilizers

Buma, Donald
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
EN_US
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This study was initiated to determine if herbaceous ornamentals would have differences in growth when fertilized with commercially available organic fertilizers and commercially available inorganic fertilizers applied at label rates and at equal nitrogen rates . Four comparisons were made: (I.) commercially available organic fertil izer at label rate - - nutrient solution at equal analysis and rate, (2) commercially available organic fertilize rate label rate--commercially available inorganic fertilizer at label rate , ( 3 )comercially available organic fertilizer at 285 mg nitrogen per month--commercially available inorganic fertilizer at 285 mg of nitrogen per month, and (4) a comparison of ommercially available organic fertilizer applied at label rate to a soil mix and to a soil less mix. The study was conducted a t Longwood Gardens' experimental greenhouses and at the University of Delaware from January to April 1976. The plants studied were Coleus 'Glory of Luxembourg', and geranium, Pelargonium hortorum 'Cherie'. Fertilizers studied were cow manure (2-1-2), fish emulsion (5-1-1), a mixture of organic fertilizers (4-5-2), a dry chemical fertilizer (8-8-8), a liquid chemical fertilizer (15-30-15) , and a slow release fertilizer (12-6-6). Commercially available inorganic fertilizers applied as directed on the label were found to produce plants with more vigorous growth...