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Fertiliser recommendations for olive based upon nutrients removed in crop and pruning

Rodrigues, M.A.; Ferreira, I.Q.; Claro, Ana Marília; Arrobas, Margarida
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.41%
The above-ground part of fourteen, young (ten-year-old), rainfed olive trees were separated into trunk (wood and bark), main branches (wood and bark), secondary branches (wood and bark), twigs, leaves and fruits. Based on the dry matter and nutrient concentration in the different tissues, the total amounts of nutrients in each tree were estimated. A controlled scheme of pruning conducted annually allowed the quantification of the amount of nutrients removed in pruning. Olive yields and nutrient concentrations in the fruits (pulp and pit) were used to quantify the nutrients removed in the crop. The results showed that the amounts of nutrients annually removed were relatively low, suggesting that more conservative fertilizer applications could be made than those usually recommended by the laboratories of soil testing and plant analysis. In this orchard, with a yield goal of 2500 kg fruit ha−1, the nitrogen (N) rate to apply as fertilizer should not exceed 20 kg N ha−1 year−1. The transient nature of N in the soil/plant systems recommends that N be applied every year to increase the nutrient-use efficiency. The application of other nutrients as fertilizer should be diagnosed beforehand by soil testing and/or plant analysis. Nutrients removed by crop and pruning do not provide all the information on the need for supplemental fertilizer applications. Soil testing and plant analysis should be used routinely for a continuous adjustment of the fertilizer program.

Test procedure for variable rate fertilizer on coffee

MOLIN, Jose Paulo; MOTOMIYA, Anamari Viegas de Araujo; FRASSON, Flavia Roncato; FAULIN, Gustavo Di Chiacchio; TOSTA, Wanderson
Fonte: UNIV ESTADUAL MARINGA, PRO-REITORIA PESQUISA POS-GRADUACAO Publicador: UNIV ESTADUAL MARINGA, PRO-REITORIA PESQUISA POS-GRADUACAO
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.32%
The objective was to develop and test a procedure for applying variable rates of fertilizers and evaluate yield response in coffee (Coffea arabica L.) with regard to the application of phosphorus and potassium. The work was conducted during the 2004 season in a 6.4 ha field located in central Sao Paulo state. Two treatments were applied with alternating strips of fixed and variable rates during the whole season: one following the fertilizing procedures recommended locally, and the other based on a grid soil sampling. A prototype pneumatic fertilizer applicator was used, carrying two conveyor belts, one for each row. Harvesting was done with a commercial harvester equipped with a customized volumetric yield monitor, separating the two treatments. Data were analyzed based on geostatistics, correlations and regressions. The procedure showed to be feasible and effective. The area that received fertilizer applications at a variable rate showed a 34% yield increase compared to the area that received a fixed rate. The variable rate fertilizer resulted in a savings of 23% in phosphate fertilizer and a 13% increase in potassium fertilizer, when compared to fixed rate fertilizer. Yield in 2005, the year after the variable rate treatments, still presented residual effect from treatments carried out during the previous cycle.

Nutrição, crescimento, eficiência de uso de água e de nutrientes em povoamentos de Eucalyptus grandis fertilizados com potássio e sódio; Tree growth, nutritional status, water use efficiency and nutrients use efficiency in Eucalyptus grandis plantation fertilized with potassium and sodium in Brazil

Almeida, Julio Cesar Raposo 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 12/08/2009 PT
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36.42%
Para avaliar os efeitos da fertilização potássica e sódica sobre a resposta do Eucalyptus grandis em crescimento, estado nutricional, eficiência de uso de água e de nutrientes foi instalado na Estação Experimental de Ciências Florestais de Itatinga (SP) em LVA distrófico (200 g kg-1 de argila) um experimento em blocos ao acaso contendo sete tratamentos: Testemunha, K1,5, K3,0, K4,5, KS3,0, Na3,0 e K1,5+Na1,5 (os valores correspondem à quantidade de K ou Na fornecidos em kmol ha-1, sob as formas de KCl, K2SO4 e NaCl). O nível crítico de K foliar variou de 6,6 a 5,0 g kg-1 e as amostragens realizadas no final da estação de chuvas (maio) sempre proporcionaram melhor avaliação do estado nutricional. A fertilização potássica elevou a resistência e/ou tolerância à ferrugem (Puccini pisidii Winter.). A concentração de Na na idade de 6 meses foliar atingiu 3,4 e 2,3 g kg-1 nos tratamentos Na3,0 e K1,5+Na1,5, mas o crescimento das árvores as concentrações reduziram para valores < 1,0 g kg-1, 36 meses pós-plantio. O Eucalyptus grandis foi capaz de absorver o Na e o transportar até as folhas, mantendo a relação K/Na >1 (elevada), uma característica relacionada às plantas tolerantes ao Na e à salinidade. A resposta do Eucalyptus grandis à fertilização potássica e sódica foi expressiva...

Calcium silicate and organic mineral fertilizer applications reduce phytophagy by Thrips palmi Karny (Thysanoptera: Thripidae) on eggplants (Solanum melongena L.)

De Almeida, Gustavo Dia; Pratissoli, Dirceu; Zanuncio, José Cola; Vicentini, Victor Bernardo; Holtz, Anderson Mathias; Serrão, José Eduardo
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 835-838
ENG
Relevância na Pesquisa
36.37%
Thrips palmi Karny (Thysanoptera: Thripidae) is a phytophagous insect associated with the reduction of eggplant productivity. The aim of this study was to evaluate the effect of calcium silicate and/or an organic mineral fertilizer, together or separately, in increasing the resistance of eggplants to T. palmi. The treatments were calcium silicate, organic mineral fertilizer, calcium silicate associated with this fertilizer and the control. Mortality and number of lesions caused by nymphs of this insect on eggplant leaves were evaluated after 3, 6, 9 and 12 leaf applications of these products. The calcium silicate and the organic mineral fertilizer reduced both the population of T. palmi and the damage caused by its nymphs, suggesting a possible increase in eggplant resistance to this pest as a result of the treatments.

Nitrogen Fertigation is Less Efficient but Safer than Granular Fertilizer Application in Newly-Planted Blueberry

Bryla, David; Machado, rui
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Artigo de Revista Científica Formato: 104831 bytes; application/pdf
ENG
Relevância na Pesquisa
36.34%
Nitrogen fertilizer methods and rates were evaluated in a new field of highbush blueberry (Vaccinium corymbosum L. `Bluecrop"). Treatments included four application methods (split fertigation, continuous fertigation, and two non-fertigated controls) and four rates of N application (0, 50, 100, and 150 kg/ha of N). Fertigation treatments were irrigated by drip and injected with dissolved ammonium sulfate fertilizer; split fertigation was applied as a triple split from April to June while continuous fertigation was applied weekly from leaf emergence to 60 d prior to the end of the season. Non-fertigated controls were fertilized with granular ammonium sulfate and irrigated by drip or microsprays. Canopy cover, which indicates the relative size of young plants, was significantly affected by the rate of N fertilizer application during the first year after planting. The interaction between N application method and rate was also significant. In general, continuous fertigation produced the lowest canopy cover among treatments at 50 kg/ha of N and the highest canopy cover at 150 kg/ha. Apparently, the other methods required less N to produce their canopy but were less responsive than continuous fertigation to additional N fertilizer applications. In fact...

Test procedure for variable rate fertilizer on coffee

Molin,José Paulo; Motomiya,Anamari Viegas de Araujo; Frasson,Flavia Roncato; Faulin,Gustavo Di Chiacchio; Tosta,Wanderson
Fonte: Editora da Universidade Estadual de Maringá - EDUEM Publicador: Editora da Universidade Estadual de Maringá - EDUEM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
Relevância na Pesquisa
36.32%
The objective was to develop and test a procedure for applying variable rates of fertilizers and evaluate yield response in coffee (Coffea arabica L.) with regard to the application of phosphorus and potassium. The work was conducted during the 2004 season in a 6.4 ha field located in central São Paulo state. Two treatments were applied with alternating strips of fixed and variable rates during the whole season: one following the fertilizing procedures recommended locally, and the other based on a grid soil sampling. A prototype pneumatic fertilizer applicator was used, carrying two conveyor belts, one for each row. Harvesting was done with a commercial harvester equipped with a customized volumetric yield monitor, separating the two treatments. Data were analyzed based on geostatistics, correlations and regressions. The procedure showed to be feasible and effective. The area that received fertilizer applications at a variable rate showed a 34% yield increase compared to the area that received a fixed rate. The variable rate fertilizer resulted in a savings of 23% in phosphate fertilizer and a 13% increase in potassium fertilizer, when compared to fixed rate fertilizer. Yield in 2005, the year after the variable rate treatments, still presented residual effect from treatments carried out during the previous cycle.

Comparative Effects of Nitrogen Fertigation and Granular Fertilizer Application on Growth and Availability of Soil Nitrogen during Establishment of Highbush Blueberry

Bryla, David R.; Machado, Rui M. A.
Fonte: Frontiers Research Foundation Publicador: Frontiers Research Foundation
Tipo: Artigo de Revista Científica
Publicado em 19/09/2011 EN
Relevância na Pesquisa
36.36%
A 2-year study was done to compare the effects of nitrogen (N) fertigation and granular fertilizer application on growth and availability of soil N during establishment of highbush blueberry (Vaccinium corymbosum L. “Bluecrop”). Treatments included four methods of N application (weekly fertigation, split fertigation, and two non-fertigated controls) and four levels of N fertilizer (0, 50, 100, and 150 kg·ha−1 N). Fertigation treatments were irrigated by drip and injected with a liquid urea solution; weekly fertigation was applied once a week from leaf emergence to 60 d prior to the end of the season while split fertigation was applied as a triple-split from April to June. Non-fertigated controls were fertilized with granular ammonium sulfate, also applied as a triple-split, and irrigated by drip or microsprinklers. Weekly fertigation produced the smallest plants among the four fertilizer application methods at 50 kg·ha−1 N during the first year after planting but the largest plants at 150 kg·ha−1 N in both the first and second year. The other application methods required less N to maximize growth but were less responsive than weekly fertigation to additional N fertilizer applications. In fact, 44–50% of the plants died when granular fertilizer was applied at 150 kg·ha−1 N. By comparison...

Effect of Silicon-Based Fertilizer Applications on the Reproduction and Development of the Citrus Mealybug (Hemiptera: Pseudococcidae) Feeding on Green Coleus

Hogendorp, Brian K.; Cloyd, Raymond A.; Swiader, John M.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
36.33%
Mealybugs are major insect pests of greenhouses, interiorscapes, and conservatories because they feed on a wide-range of horticultural crops. Furthermore, mealybugs are difficult to regulate with insecticides due to the presence of a nearly impervious protective waxy covering, which means that alternative management strategies are required. As such, this study, involving two replicated experiments, was designed to determine the value of applying silicon-based fertilizers, as potassium silicate, to coleus, Solenstemon scutellarioides (L.) Codd, plants as a way to prevent outbreaks of the citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae). The first experiment evaluated the effects of different application methods (foliar and drench), at 50 ppm silicon, using the commercially-available product, ProTek 0-0-3 The Silicon Solution. The second experiment entailed applying the silicon-based fertilizer as a drench to the growing medium at different rates (0, 100, 400, 800, and 1,600 ppm silicon). We determined the effects of the silicon-based fertilizer treatments on citrus mealybug life history parameters including number of eggs laid by the adult female, body size, and developmental time from first instar to ovipositing adult female. Furthermore...

Incomplete Markets and Fertilizer Use : Evidence from Ethiopia

Zerfu, Daniel; Larson, Donald F.
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
46.43%
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...

A Conceptual Model of Incomplete Markets and the Consequences for Technology Adoption Policies in Ethiopia

Larson, Donald F.; Gurara, Daniel Zerfu
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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36.42%
In Africa, farmers have been reluctant to take up new varieties of staple crops developed to boost smallholder yields and rural incomes. Low fertilizer use is often mentioned as a proximate cause, but some believe the problem originates with incomplete input markets. As a remedy, African governments have introduced technology adoption programs with fertilizer subsidies as a core component. Still, the links between market performance and choices about using fertilizer are poorly articulated in empirical studies and policy discussions, making it difficult to judge whether the programs are expected to generate lasting benefits or to simply offset high fertilizer prices. This paper develops a conceptual model to show how choices made by agents supplying input services combine with household livelihood settings to generate heterogeneous decisions about fertilizer use. An applied model is estimated with data from a panel survey in rural Ethiopia. The results suggest that adverse market conditions limit the adoption of fertilizer-based technologies...

Cambodia Quality Assessment Report

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
36.46%
In response to numerous reports and claims of poor quality or fake fertilizer that were extensively reported by farmers, fertilizer dealers, and government officials of the Ministry of Agriculture, Forestry, and Fisheries (MAFF) over the past three years, the World Bank, in support of the Royal Government of Cambodia and in response to the food crisis through the smallholder agricultural and social protection support development policy operation (DPO) engaged the international fertilizer development center (IFDC) to perform a rapid appraisal of fertilizer quality in Cambodia. A total of 103 samples of fertilizer were collected for analysis of quality from 26 fertilizer dealers and three importers. Six Cambodian farmers were interviewed and three fertilizer manufacturers were visited and interviewed in Ho Chi Minh city, Vietnam. The field investigations involved extensive interviews and discussions with public and private stakeholders and site visits to fertilizer dealer shops and warehouse locations. It is essential that the Department of Agricultural Legislation in Cambodia and the field inspectors have access to reliable and fast fertilizer analytical services as visual inspections cannot detect product adulteration or below-guarantee analysis.

Effects of N-fertilizer rate and placement on wheat (Triticum aestivum) establishment, growth and yield

Kleemann, S.; Gill, G.; Coventry, D.
Fonte: The Regional Institute; http://www.cropscience.org.au/icsc2004/poster/2/5/1/1254_kleemanns.htm Publicador: The Regional Institute; http://www.cropscience.org.au/icsc2004/poster/2/5/1/1254_kleemanns.htm
Tipo: Conference paper
Publicado em //2004 EN
Relevância na Pesquisa
36.32%
In the 2000 and 2001 growing seasons, field experiments evaluating the effects of N-fertilizer rate and placement on establishment, growth and grain yield of wheat were undertaken at Roseworthy, South Australia. Wheat seedling establishment was significantly reduced in 2000 (85%) and 2001 (67%) when high rates of N-fertilizer were placed with the seed. However, toxicity was mostly (2000) or partially (2001) avoided when high rates of N-fertilizer were either banded below or to the side of the seed providing adequate separation between seed and fertiliser. In 2000, there was evidence of high N uptake when banded N increased dry matter (DM) production, however there were no corresponding grain yield or protein benefits. In the 2001 season, there were small N-fertilizer responses in grain yield and protein. However, irrespective of N placement, the crop did not benefit from amounts of N input potentially put in the canopy. From a practical view this study has shown that one-off applications of N-fertilizer, although safer when banded did not necessarily position the crop for higher yields and or protein.

Comparing of the difference and balance methods to calculate percent recovery of fertilizer phosphorus applied to soils: a critical discussion

Chien, S.H.; Sikora, F.J.; Gilkes, R.J.; McLaughlin, M.J.
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
36.38%
This article presents a critical discussion comparing the traditional method and a newly proposed balance method to calculate percent recovery of fertilizer P applied to soils. The traditional difference method is defined as P uptake from the soil treated with fertilizer P minus P uptake from a control with no P added divided by the amount of fertilizer P applied. The balance method simply considers the ratio of P uptake from the P fertilized soil to the amount of fertilizer P applied and does not use a control to discount P taken up from soil without fertilizer application. The percentage recovery of fertilizer P calculated by the difference method normally ranges from 10 to 25% for a given crop in a given season and is always lower than that by the balance method which ranges from 50 to 90% and is sometimes over 100%. The balance method is inappropriate to calculate percentage recovery of current fertilizer P applied due to its overestimation and the invalidity of the mathematical equation used. The difference method is superior to the balance method to estimate percentage recovery of fertilizer P applied. The balance method is suitable for determining a percent soil P balance to evaluate if fertilizer P applications are building up...

Understanding the Agricultural Input Landscape in Sub-Saharan Africa : Recent Plot, Household, and Community-Level Evidence

Sheahan, Megan; Barrett, Christopher B.
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
36.32%
Conventional wisdom holds that Sub-Saharan African farmers use few modern inputs despite the fact that most growth-inducing and poverty-reducing agricultural growth in the region is expected to come largely from expanded use of inputs that embody improved technologies, particularly improved seed, fertilizers and other agro-chemicals, machinery, and irrigation. Yet following several years of high food prices, concerted policy efforts to intensify fertilizer and hybrid seed use, and increased public and private investment in agriculture, how low is modern input use in Africa really? This paper revisits Africa's agricultural input landscape, exploiting the unique, recently collected, nationally representative, agriculturally intensive, and cross-country comparable Living Standard Measurement Study-Integrated Surveys on Agriculture covering six countries in the region (Ethiopia, Malawi, Niger, Nigeria, Tanzania, and Uganda). The study uses data from more than 22,000 households and 62,000 plots to investigate a range of commonly held conceptions about modern input use in Africa...

Soil Fertility, Fertilizer, and the Maize Green Revolution in East Africa

Matsumoto, Tomoya; Yamano, Takashi
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
46.41%
This paper investigates the reasons for the low application of external fertilizers on farms in Kenya and Uganda. The analysis uses a large panel of household data with rich soil fertility data at the plot level. The authors control for maize seed selection and household effects by using a fixed-effects semi-parametric endogenous switching model. The results suggest that Kenyan maize farmers have applied inorganic fertilizer at the optimal level, corresponding to the high nitrogen-maize relative price, in one of the two survey years and also responded to the price change over time. In Uganda, even the low application of inorganic fertilizer is not profitable because of its high relative price. The authors conclude that policies that reduce the relative price of fertilizer could be effective in both countries, while the efficacy of policies based on improving farmers' knowledge about fertilizer use will be limited as long as the relative price of fertilizer remains high.

Africa’s Growing Soil Fertility Crisis : What Role For Fertilizer?

Agwe, Jonathan; Morris, Michael; Fernabdes, Erick
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Publications & Research :: Brief; Publications & Research
ENGLISH
Relevância na Pesquisa
46.41%
Reversing Africa's decades-long decline in soil productivity levels poses a major challenge, and one that cannot be addressed without increased use of appropriate fertilizer nutrients. The 2006 World Bank Africa Fertilizer Strategy Assessment was undertaken to inform policy makers, providing them with guidelines on measures to effectively raise fertilizer use. This Note draws upon the material prepared for the above fertilizer strategy assessment, summarizes the information on the approaches to enhancing fertilizer supply and use in Africa, and identifies some future steps.

The Effects of Manure and Nitrogen Fertilizer Applications on Soil Organic Carbon and Nitrogen in a High-Input Cropping System

Ren, Tao; Wang, Jingguo; Chen, Qing; Zhang, Fusuo; Lu, Shuchang
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 15/05/2014 EN
Relevância na Pesquisa
36.52%
With the goal of improving N fertilizer management to maximize soil organic carbon (SOC) storage and minimize N losses in high-intensity cropping system, a 6-years greenhouse vegetable experiment was conducted from 2004 to 2010 in Shouguang, northern China. Treatment tested the effects of organic manure and N fertilizer on SOC, total N (TN) pool and annual apparent N losses. The results demonstrated that SOC and TN concentrations in the 0-10cm soil layer decreased significantly without organic manure and mineral N applications, primarily because of the decomposition of stable C. Increasing C inputs through wheat straw and chicken manure incorporation couldn't increase SOC pools over the 4 year duration of the experiment. In contrast to the organic manure treatment, the SOC and TN pools were not increased with the combination of organic manure and N fertilizer. However, the soil labile carbon fractions increased significantly when both chicken manure and N fertilizer were applied together. Additionally, lower optimized N fertilizer inputs did not decrease SOC and TN accumulation compared with conventional N applications. Despite the annual apparent N losses for the optimized N treatment were significantly lower than that for the conventional N treatment...

Economic analysis of organic greenhouse lettuce production in Turkey

Engindeniz,Sait; Tuzel,Yuksel
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2006 EN
Relevância na Pesquisa
36.39%
Health issues and environmental concerns have drawn the attention to organic agriculture aiming to protect the natural balance and to produce without damaging the environment. This study aims determining economic feasibility of organic greenhouse lettuce (Lactuca sativa L.) in an on farm trial, to foster organic greenhouse vegetable production in the preservation area of Tahtali Dam, projected as the sole water resource of Izmir, Turkey's third largest. A 384 m² greenhouse, constructed of galvanized metal tubing anchored and covered with a polyethylene was analyzed to identify typical operation procedures, and to determine unitary construction and operation cost. Organic lettuces were produced during autumn season of 2001-2002, testing different organic fertilizer applications, including two rates of farmyard and poultry manure (30 and 50 t ha-1) with and without two organic fertilizers based on either bacteria or algae. Economical analysis was performed according to different organic fertilizer applications. Cost, yield, and price data were analyzed to determine the profitability of a typical operation. Net return obtained from organic lettuce growing ranged between us $ 0.376 and us $ 0.901 m-2, as a result of different fertilizer applications.

Análise econômica da produção orgânica de alface em estufas na Turquia; Economic analysis of organic greenhouse lettuce production in Turkey

Engindeniz, Sait; Tuzel, Yuksel
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/06/2006 ENG
Relevância na Pesquisa
36.39%
Preocupações sanitárias e ambientais têm atraído a atenção para a prática da agricultura orgânica como meio de proteger o balanço ambiental e produzir sem danificar o ambiente. Este estudo objetiva determinar a viabilidade econômica da produção em estufa da alface (Latuca sativa L.) em um ensaio de campo, a fim de incentivar a produção orgânica de vegetais na área de preservação do Reservatório Tahtali, projetado como o único recurso hídrico de Izmir, a terceira maior cidade da Turquia. Uma estufa de tubos galvanizados (384 m²), ancorados e cobertos com polietileno, foi analisada para identificar procedimentos operacionais padronizados e determinar custos unitários de construção e operação. Alfaces orgânicas foram produzidas no outono de 2001-2002, testando diferentes aplicações de sobras compostadas e esterco de granja avícola como fertilizantes orgânicos (30 e 50 t ha-1), com ou sem a adição de fertilizantes comerciais bacterianos ou algais. A análise econômica foi feita de acordo com as quantidades de fertilizantes utilizadas. A determinação da lucratividade foi feita com base na análise de dados de custos, produtividade e preço. O lucro líquido obtido da produção orgânica de alface em estufa variou entre US$ 0.376 e US$ 0.901 m-2.; Health issues and environmental concerns have drawn the attention to organic agriculture aiming to protect the natural balance and to produce without damaging the environment. This study aims determining economic feasibility of organic greenhouse lettuce (Lactuca sativa L.) in an on farm trial...

Calcium silicate and organic mineral fertilizer applications reduce phytophagy by Thrips palmi karny (Thysanoptera: thripidae) on eggplants (Solanum melongena L.)

Dia de Almeida,Gustavo; Pratissoli,Dirceu; Cola Zanuncio,José; Bernardo Vicentini,Victor; Mathias Holtz,Anderson; Serrão,José Eduardo
Fonte: ASOCIACIÓN INTERCIENCIA Publicador: ASOCIACIÓN INTERCIENCIA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2008 EN
Relevância na Pesquisa
36.37%
Thrips palmi Karny (Thysanoptera: Thripidae) is a phytophagous insect associated with the reduction of eggplant productivity. The aim of this study was to evaluate the effect of calcium silicate and/or an organic mineral fertilizer, together or separately, in increasing the resistance of eggplants to T. palmi. The treatments were calcium silicate, organic mineral fertilizer, calcium silicate associated with this fertilizer and the control. Mortality and number of lesions caused by nymphs of this insect on eggplant leaves were evaluated after 3, 6, 9 and 12 leaf applications of these products. The calcium silicate and the organic mineral fertilizer reduced both the population of T. palmi and the damage caused by its nymphs, suggesting a possible increase in eggplant resistance to this pest as a result of the treatments.