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"Manejo da adubação nitrogenada na cultura do milho após cultivo da soja em sistema semeadura direta no Cerrado"; Management of corn crop nitrogen fertilization after soybean cultivation on no tillage system at the Brazilian Cerrado

Lange, Anderson
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 02/08/2006 PT
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46%
O cultivo de plantas de cobertura como cultura de inverno para produzir palha e proteger o solo após a colheita da cultura de verão, na região do Cerrado brasileiro, tem sido um dos maiores desafios para os produtores que optaram pela adoção do sistema semeadura direta. Outra dificuldade inerente ao sistema semeadura direta, com peculiaridade para o Cerrado, refere-se ao manejo do nitrogênio (N) na cultura do milho, já que o ciclo deste nutriente é extremamente dependente das condições climáticas, apresentando, por isto, comportamento diferente da região Sul do país. Nesta situação, a aplicação de N na semeadura da cultura de cobertura de solo com o objetivo de aumentar a produção de palha ou em pré-semeadura da cultura principal, buscando otimizar tempo, pode ser uma estratégia que apresente a mesma eficiência da fertilização na cobertura no milho em sucessão à soja. Os objetivos do estudo foram avaliar a produção de massa de matéria seca de culturas de cobertura de solo e de espécies espontâneas; determinar a influência das épocas da fertilização nitrogenada nos caracteres fenológicos, na produtividade de grãos e de massa de matéria seca da cultura do milho cultivado após 2 anos de soja e, também...

Níveis de salinidade e manejo da fertirrigação sobre o cultivo do tomateiro (Lycopersicon esculentum Mill) em ambiente protegido; Salinity control and fertigation management on the cultivation of tomato (Lycopersicon esculentum Mill) in greenhouse

Eloi, Waleska Martins
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 26/10/2007 PT
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A necessidade crescente de aumentar a produtividade no setor agrícola levou ao acréscimo do uso de fertilizantes na produção de alimentos, ocasionando, entre outras coisas, a salinização do solo, as conseqüências para a saúde do homem e o impacto ambiental, não são totalmente conhecidas. O presente trabalho teve como objetivo avaliar o efeito de diferentes níveis de salinidade no solo provocada pelo uso da fertirrigação, nas variáveis fenológicas e de produção do tomateiro cultivado em estufa; estudar a evolução da salinização do solo cultivado com tomateiro sob dois tipos de manejo da fertirrigação, o tradicional, baseado na marcha de absorção de nutrientes da cultura e o baseado no monitoramento da solução do solo, avaliando o funcionamento do uso de cápsulas porosas, como extratores de solução do solo, visando o controle da salinização. O experimento foi conduzido em duas etapas, sendo a primeira desenvolvida no Laboratório de Solos e a segunda realizada em estufa plástica, ambos localizados no Departamento de Engenharia Rural da ESALQ/USP, em Piracicaba. A primeira etapa consistiu de testes preliminares que possibilitaram a construção de curvas artificiais de salinização, visando à realização do processo de salinização artificial do solo. Na segunda etapa avaliou-se o efeito dos diferentes níveis iniciais de salinidade do solo e manejos aplicados. Os níveis iniciais de salinidade utilizados foram: S1 = 1...

Manejo da fertirrigação em ambiente protegido visando o controle da salinidade para a cultura do pepino enxertado; Management of the fertirrigation in protecting environment aiming the control of the salinity for culture of grafted cucumber

Medeiros, Pedro Róbinson Fernandes de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 18/01/2008 PT
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Com o intuito de contribuir para os estudos referentes à tolerância e efeitos da salinidade causada por excesso de fertilizantes nas principais culturas exploradas nacionalmente, o presente trabalho teve como objetivos estudar os efeitos de diferentes níveis de salinidade do solo sobre as variáveis fenológicas e de produção do pepino cultivado em vasos e em ambiente protegido, e averiguar se a manutenção da condutividade elétrica em um determinado nível promove incremento da produção quando contrastada com o manejo tradicional da fertirrigação. Este estudo foi conduzido na experimental do Departamento de Engenharia Rural da ESALQ/USP, Piracicaba, SP. Os tratamentos foram compostos da combinação de dois fatores: 6 níveis de salinidade inicial do solo (S1 = 1,5; S2 = 2,5; S3 = 3,5; S4 = 4,5; S5 = 5,5 e S6 = 6,5 dS m-1) e dois manejos de fertirrigação: tradicional (M1) e com controle da condutividade elétrica da solução do solo (M2). O delineamento estatístico adotado foi o de blocos casualizados completos com quatro repetições, ficando os fatores estudados arranjados no esquema fatorial 6 x 2. A salinização inicial do solo se procedeu por meio da aplicação de soluções salinas preparadas a partir 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
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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
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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...

Efeitos diretos e indiretos de fertilizantes sobre comunidades aquáticas experimentais; Direct and indirect effects of fertilizers on experimental aquatic communities

Santos, Bianca Gonçalves dos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 12/07/2013 PT
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A demanda da população humana por alimentos, fibras e biocombustíveis impõe crescimento pronunciado na agricultura intensiva e, com ela, no consumo de fertilizantes. Este manejo de fertilizantes leva a alterações dramáticas nas quantidades e proporções de nutrientes em agroecossistemas que, por sua vez, podem influenciar comunidades biológicas por meio de alterações na biomassa, qualidade nutricional e composição de produtores. Uma tendência no cenário produtivo brasileiro recente é a expansão das culturas de biocombustíveis, notadamente da cana-de-açúcar (etanol) e da soja (biodiesel), sobre ambientes de cerrado. Estas culturas, que juntas cobrem nada menos que 30 milhões de hectares do território brasileiro, demandam padrões contrastantes de fertilização. A cana-de-açúcar exige altas proporções de nitrogênio relativo a fósforo, enquanto que a soja exige altas proporções de fósforo relativo a nitrogênio. Esta dissertação teve como objetivo testar os efeitos diretos e indiretos que as alterações nas quantidades e proporções de N e P que se seguem à conversão de ambientes nativos para o cultivo de cana-de-açúcar e soja têm sobre comunidades biológicas. Estes objetivos foram testados por meio de dois experimentos em mesocosmos aquáticos manipulando nutrientes...

Juglans growth under ploughing and Vicia villosa sowing understory management

Homar-Sanchez, C.A.; Urbán-Martínez, I.; Rigueiro-Rodriguez, A.; Mosquera-Losada, R.
Fonte: EURAF Publicador: EURAF
Tipo: Outros
Publicado em /06/2014 ENG
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Poster; Inorganic fertilization has a clear impact on farm economy and on carbon footprint. Input reduction of mineral fertilizers will reduce the impact of this activity on GHG emissions as fertilizers produced in the farms should not be transported. This paper aims at reducing the inputs of nitrogen in a plantation of Juglans hybrid carried out in 2004. The experiment started in 2010 when six-year old trees had 11.4 dbh and 7.3 m of height. The experiment followed a desing of randomized block with two replicas. Treatments consisted of a sowing of Vicia villosa in alleys established at both sides of trees or ploughing. Vicia villosa sowing improved tree dbh and increased tree leaves concentrations of nitrogen and phosphorous.

Weed control under integrated nutrient management systems in faba bean (Vicia faba) production in Egypt

El-Metwally,I.M.; Abdelhamid,M.T.
Fonte: Sociedade Brasileira da Ciência das Plantas Daninhas Publicador: Sociedade Brasileira da Ciência das Plantas Daninhas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 EN
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Two field experiments were conducted in two successive seasons, 2005/2006 and 2006/2007, to determine whether management can improve faba bean competitiveness with weeds, thus helping to achieve its yield potential. The experiment included five treatments, composed of organic and mineral fertilizers, alone and mixed at different rates, along with a control and six weed control treatments, including oxadiargyl, prometryn, hand hoeing treatments alone or mixed with the herbicides, and a nonweeded treatment (control).The herbicide treatments were not superior to the two hand-hoeing treatments. Using compost favored growth and yield of faba bean more than of weeds. Adding fertilizer also improved most yield parameters. Application of compost alone or combined with 50 or 100% of the recommended NPK rate improved faba bean growth in terms of net assimilation rate, specific leaf area, and leaf weight ratio as components of relative growth rate. This improvement in growth resulted in increase of seed yield, yield components and protein of faba bean. Faba bean yield performance improved under interactive fertilizer effects and weed control treatments as growth improved, as a result of nutrient release from fertilizers and weed control.

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
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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...

Biomass flow in Tifton-85 bermudagrass canopy subjected to different management strategies under rotational grazing with dairy goats.

CUTRIM JÚNIOR, J. A. A.; CAVALCANTE, A. C. R.; CÂNDIDO, M. J. D.; SILVA, G. L.; OLIVEIRA, L. E. V.; VASCONCELOS, E. C. G.; MESQUITA, T. M. O.
Fonte: Revista Brasileira de Zootecnia, Viçosa, MG, v. 42, n. 2, p. 77-86, 2013. Publicador: Revista Brasileira de Zootecnia, Viçosa, MG, v. 42, n. 2, p. 77-86, 2013.
Tipo: Artigo em periódico indexado (ALICE)
EN
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Biomass flow characteristics and forage accumulation were evaluated in Bermudagrass (Tifton 85) pasture managed under intermittent stocking with different management strategies. The management levels utilized were conventional (10 cm residual height and unfertilized), light (20 cm residual height and unfertilized), moderate (20 cm residual height with fertilization of 300 kg N/ha.year) and intensive (10 cm residual height with fertilization of 600 kg N/ha.year). A randomized design was used with repeated measurements over time, in two periods of the year, with four replicates. There was significant effect of management × period of the year on the leaf elongation rate (LER). The management levels under fertilization (0.59 and 0.60 cm/tiller.day for the intensive and moderate management, respectively) and the rainy season (0.49 cm/tiller.day) showed the greatest stem elongation rate. Leaf senescence rate (LSR) before and after and total LSR were modified by the management × period of the year interaction. The intensive management, with 0.38 leaves/tiller.day, as well as the dry period, with 0.27 leaves/tiller.day, showed higher leaf appearance rate. The lowest phyllochron was observed in intensive management and dry periods, as well as an interaction with the management of the same periods of the year. There was management × period of year interaction effect on leaf lifespan; the highest value was found under conventional management and dry period. Both production and forage accumulation rates were higher in the intensive and moderate management levels and dry season...

Phosphorus management for perennial crops in the Amazon.

CRAVO, M. da S.; LEHMANN, J.; MACEDO, J. L. V.
Fonte: In; GERMAN-BRAZILIAN WORKSHOP ON NEOTROPICAL ECOSYSTEMS, 2000, Hamburg. Program and abstracts... Hamburg: University, 2000. Publicador: In; GERMAN-BRAZILIAN WORKSHOP ON NEOTROPICAL ECOSYSTEMS, 2000, Hamburg. Program and abstracts... Hamburg: University, 2000.
Tipo: Resumo em anais de congresso (ALICE) Formato: p. 33.
EN
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Study on the phosphorus management for perennial crops in the Amazonas state (Brasil).; 2000

Arab Republic of Egypt : Integrated Water Resources Management Plan

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
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The challenges facing the water sector in Egypt are enormous and require the mobilization of all resources and the management of these resources in an integrated manner. Changes in the way water resources are currently allocated and managed are inevitable. Accordingly, a National Water Resources Plan for Egypt (NWRP) was launched. The NWRP is a comprehensive document which describes how Egypt will safeguard its water resources in the future, both with respect to quantity and quality, and how it will use these resources in the best way from a socio-economic and environmental point of view. The NWRP needs to be augmented by a transitional strategy including further reform interventions which ensure smooth and enhanced streamlining with Integrated Water Resources Management principles and approaches. The current integrated water resources management plan (IWRM Plan) has been prepared to serve the later concerns and is intended to be a complementary, action-oriented, implementation framework to the NWRP. It addresses the gaps in NWRP and provides for additional measures and provisions which facilitate the transition towards an integrated management approach within the water sector. The IWRM Plan assesses the current water resources management setup and practices along with the ongoing reform efforts led by the MWRI. The Plan identifies the actions agreed upon as major interventions to pursue an effective integrated framework for water management over the next 15 years. Thirty Nine actions falling under 11 major categories are proposed: Institutional reform and strengthening; policies and legislations; physical interventions; capacity building; technological and information systems; water quality; economic and financial framework; research; raising awareness for IWRM; monitoring and evaluation; and trans-boundary cooperation.

Improving Soil Fertility Management in Sub-Saharan Africa

Donovan, Graeme; Casey, Frank
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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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...

Assessing the Carbon Benefits of Improved Land Management Technologies

Braimoh, Ademola
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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Ensuring food security under changing climate conditions is one of the major challenges of our era. Agriculture must not only become increasingly productive, but must also adapt to climate change while reducing greenhouse gas emissions. Soil carbon sequestration, the process by which atmospheric carbon dioxide is taken up by plants through photosynthesis and stored as carbon in biomass and soils, can support these goals. First, soil carbon enhances agricultural productivity, which reduces rural poverty; second, it limits greenhouse gas concentrations in the atmosphere; and third, it reduces the impact of climate change on agricultural ecosystems. This smart lesson describes the potential benefits of selected land management technologies that sequester carbon.

From Users to Custodians : Changing Relations between People and the State in Forest Management in Tanzania

Wily, Liz Alden; Dewees, Peter A.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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Central control of forests takes management responsibility away from the communities most dependent on them, inevitably resulting in tensions. Like many African countries, Tanzania--which has forest or woodland cover over 30-40 percent of its land--established central forestry institutions at a time when there was little need for active management and protection because population pressures were low. But in the face of scarce public resources and burgeoning demand from the growing population for agricultural landand woodland products, there has been growing recognition of the need to bring individuals, local groups, and communities into the policy, planning, and management process if woodlands are to remain productive in the coming decades. Tanzania established its first three community-owned and -managed forest reserves in September 1994. Today, supported by substantive policy reforms that largely grew out of the early experiences with community-based management, more than 500 villages own and manage forest reserves...

Environmental Management in Bolivia : Innovations and Opportunities

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
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Pollution management is at the top of the development agenda of Bolivia, and this program helps address it in a cross-sectoral manner. In the context of the implementation of the program environmental management in Bolivia: innovations and opportunities which was conducted from September 2010 until October 2012, the World Bank has implemented a technical assistance program and supported a multisectoral analysis in order to help the Bolivian government improve environmental management in four specific areas: (a) water resource pollution by mining and mitigation of the pollution; (b) evaluation of potential wastewater reuse in agriculture with case studies from Cochabamba and Tarija; (c) improvement of waste management; and (d) evaluation of health benefits through adequate water supply and basic sanitation. The program s overall objective is to help strengthen environmental management in critical areas of the pollution management agenda. This report summarizes the outcomes of the pillar of the program on analytical services and is divided into five chapters: (1) improved water supply...

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
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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...

Sustainable Pest Management : Achievements and Challenges

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Other Agricultural Study; Economic & Sector Work
ENGLISH; EN_US
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The objective of this paper is to: (a) review World Bank's pest management activities during 1999-2004; (b) assess those in view of the changes in the external and internal contexts; (c) identify appropriate opportunities of engagement on pest and pesticide issues; and (d) suggest means to further promote sound pest management in the World Bank operations. The importance of sound pest management for sustainable agricultural production is being recognized by many developing countries. Many countries have adopted sound pest management and Integrated Pest Management (IPM) policies authorizing plant protection services to coordinate the promotion of good practices. These policies provide the institutional framework for the planning and implementation of pest management.

Mortality of the yellow mealworm Tenebrio molitor exposed to fertilizers and herbicides commonly used in agriculture

Castilla, Aurora M.; Dauwe, T.; Mora, I.; Palmer, Miquel; Guitart, R.
Fonte: Masson Publicador: Masson
Tipo: Artículo Formato: 134469 bytes; application/pdf
ENG
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5 pages.; A preliminary screening test was performed to examine whether fertilizers or herbicides commonly used by farmers affect the development and mortality of the grain beetle Tenebrio molitor (mealworms). Mealworms (n = 300) were exposed for four weeks to four different treatments: organic liquid fertilizer (pig manure), organic solid fertilizer (turkey litter), mineral fertilizer (nitrates), and herbicides (a mixture of glyphosate and 2,4-D). After four weeks in direct contact with all treatments, mealworm mortality ranged from 74 % to 88 %. Surprisingly, control mealworms placed in the same room with the other treatments also experienced high mortality (72 %) while mortality of control-isolated mealworms was low (8 %), suggesting that volatile compounds from tested products can be noxious to larval insects. Because Tenebrio larvae and other insects are the main food source for many birds, lizards and other wildlife, organic fertilizers from farms should be adequately treated before being dispersed in the field. Also, mineral fertilizers and herbicides should be used with moderation and in the prescribed proportions.; Peer reviewed

Effect of integrated soil fertility management interventions on the abundance and diversity of soil Collembola in Embu and Taita Districts, Kenya

Muturi,J. J.; Mbugi,J. P.; Mueke,J. M.; Lagerlöf,J.; Mung'atu,J. K.; Nyamasyo,G.; Gikungu,M
Fonte: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria Publicador: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
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The study aimed at identifying soil fertility management practices that promote the Collembola population, diversity and survival in the soil. Soil samples were randomly collected from on farm plots amended with: 1-Mavuno ((Ma)-is a compound fertilizer containing 26% Potassium, 10% Nitrogen, 10% Calcium, 4% Sulphur, 4% Magnesium and trace elements like Zinc, Copper, Boron, Molybdenum and Manganese)), 2-Manure (Mn), 3-Trichoderna (Tr) inoculant (is a soil and compost-borne antagonistic fungus used as biological control agent against plant fungal diseases), 4-Farmers practice ((FP) where Tripple Super Phosphate (T.S.P.) and Calcium Ammonium Nitrate (C.A.N.) fertilizers are applied in the soil in mixed form), 5-Tripple Super Phosphate (T.S.P.), 6-Calcium Ammonium Nitrate (C.A.N.). These treatments were compared with 7-Control (Co) (where soil fertility management interventions where not applied). Soil Collembola were extracted using dynamic behavioural modified Berlese funnel and identified to the genus level. Occurrence of Collembola was significantly affected by soil fertility amendments in both Taita and Embu study sites (P<0.05). Twenty two genera of soil dwelling Collembola were recorded, with control and organic manure treated plots recording high diversity with a Shannon 1.86 in Embu and a Shannon 2.09 in Taita...