Influence of Soil and Foliar Application of Nutrients on Growth and Yield of Black Gram (Vigna mungo L)

Aims: This study aims to scrutinize the intricacies of nutrient management to optimize the cultivation of black gram (Vigna mungo L.) during the Rabi season of 2022-2023 in Coimbatore. The primary objectives include evaluating the efficacy of various treatments, such as recommended doses of inorganic fertilizer (RDF), rhizobium, and Phosphobacteria microbial inoculants as soil applicants, as well as TNAU Pulse Wonder, nano urea, and DAP as foliar sprays.Study Design: A meticulous Randomized Block Design (RBD) with three replications was employed to explore diverse treatments. This design allowed for a systematic investigation into the impact of different nutrient management strategies on the growth and yield of black grams.Place and Duration of Study: The study was conducted in Coimbatore, and the Rabi season of 2022-2023 was chosen for its duration. The experimental setup was established at the research farm under the auspices of the Karunya Institute of Technology and Sciences.Methodology: A total of ten treatments were tested, including various combinations of RDF (25:50:25), rhizobial culture, phosphobacteria, TNAU Pulse Wonder, nano urea, and DAP. Plant growth metrics, such as plant height and leaf count, were measured at 60 days after sowing (DAS). Yield attributes, including pod count, seeds per pod, and test weight, were also evaluated. Economic scrutiny included the calculation of the cost of cultivation, gross return, net income, and benefit-cost ratio.Results: Treatment T7, consisting of 75% RDF, rhizobial culture, phosphobacteria, and 1% TNAU Pulse Wonder, demonstrated substantial efficacy in enhancing plant growth metrics. At 60 DAS, this treatment exhibited an appreciable increase in plant height (39.89 cm) and leaf count (15.33). Moreover, T7 positively impacted crucial yield attributes, with elevated pod count (24.33), seeds per pod (9.33), and test weight (4.98 g). Economic scrutiny identified T7 as the epitome of economic viability, featuring a cost of cultivation at 30,240 INR, gross return of 125,587.80 INR, net income of 95,347.80 INR, and a commendable benefit-cost ratio of 4.15.Conclusion: These findings underscore the profound significance of strategic nutrient management paradigms for fostering sustainable and economically robust black gram cultivation. The identified treatment T7 stands out as a promising approach to optimize yields and economic returns in black gram cultivation, offering valuable insights for future agricultural practices.

Factores clave y tendencias en los sistemas acuapónicos: revisión de literatura / Key factors and trends in aquaponic systems: literature review

RESUMEN La acuaponía es un sistema de producción que integra la acuicultura y la hidroponía, se destaca por su capacidad de producir alimentos de forma sostenible, promoviendo el reciclaje de nutrientes, el uso eficiente del agua y generando alimentos de alta calidad e inocuidad. Por ese motivo, el objetivo de este artículo de revisión fue compilar los conceptos más relevantes y avances alcanzados en la aplicación de esta técnica productiva mediante la exploración y sistematización de investigaciones publicadas en bases de datos de revistas indexadas durante la década 2012-2022. Los resultados obtenidos se organizaron en cuatro grandes categorías: 1. La acuaponía desde una perspectiva biológica; 2. viabilidad y rentabilidad del sistema acuapónico; 3. desarrollos ingenieriles, nuevas tendencias y tecnologías en acuaponía; y 4. aspectos ambientales y sociales de la acuaponía. La información científica y tecnológica compilada permitirá conocer el potencial, la viabilidad y adaptabilidad de los sistemas acuapónicos en un contexto de cambios ambientales, sociales y económicos. En ese sentido, la bibliometría, realizada con 55 publicaciones seleccionadas, permite identificar que el año de mayor producción científica en sistemas acuapónicos fue 2020, con 23% de la producción total en la década analizada, y que el 63% de las investigaciones se publicó en los últimos cinco años (2018 a 2022). Finalmente, por área temática, se encontró que el 44% de las investigaciones realizadas corresponden a la categoría "desarrollos ingenieriles, nuevas tendencias y tecnologías", seguido por la "perspectiva biológica" y "aspectos ambientales y sociales" con 28% y 20%, respectivamente. El área con menor cantidad de publicaciones correspondió a "viabilidad y rentabilidad" (8% del total de referencias).

ABSTRACT Aquaponics, a production system that integrates aquaculture and hydroponics, stands out for its ability to produce food sustainably, promoting the recycling of nutrients, the efficient use of water and generating high quality and safe foods. For this reason, the objective of this review article was to compile the most relevant concepts and advances achieved in the application of this productive technique, through exploration and systematization of research published in indexed journal databases during the decade between 2012 to 2022. Results obtained were organized into four large categories: 1. Aquaponics from a biological perspective; 2. viability and profitability of aquaponic systems; 3. engineering developments, new trends and technologies in aquaponics; and 4. environmental and social aspects of aquaponics. The information presented below will allow to know the potential feasibility and adaptability of aquaponic systems in the context of environmental, social, and economic changes. In this sense, bibliometrics, carried out in 55 selected publications, allows to identify the year 2020 as the highest scientific production in aquaponic systems with 23% of total production in the decade studied and that 63% of research was published in the last 5 years (2018 to 2022). Finally, by thematic area, it was found that 44% of the research carried out corresponds to the "engineering developments, new trends and technologies" category, followed by "biological perspective", and "environmental and social aspects" (28% and 20%, respectively). The area with the lowest quantity of publications corresponded to "viability and profitability" (8% of the total references).

A meta-analysis of biochar application to manage plant diseases caused by bacterial pathogens

The current agricultural scenario faces diverse challenges, among which phytosanitary issues are crucial. Plant diseases are mostly treated with chemicals, which cause environmental pollution and pathogen resistance. In light of the UN Sustainable Development Goals (SDGs), the biochar alternative use to chemical inputs fits into at least six of the proposed goals (2, 3, 7, 13, 15, and 17), highlighting the 12th, which explains responsible consumption and production. Biochar is valuable for inducing systemic resistance in plants because it is a practical and frequently used resource for improving physical, chemical, and biological soil attributes. This review assessed the beneficial and potential effects of applying biochar to agricultural soils on bacterial pathogen management. Such application is a recent strategy; therefore, this research evaluated 20 studies that used biochar to manage plant diseases caused by pathogens inhabiting the soil in different systems. The effectiveness of biochar application in controlling plant diseases has been attributed to its alkaline pH, which contributes to the growth of beneficial microorganisms and increases nutrient availability, and its porous structure, which provides habitat and protection for soil microbiome development. Therefore, the combined effect of improvements on soil attributes through biochar application aids pathogen control. Biochar application helps manage plant diseases through different mechanisms, inducing plant resistance, increasing activities and abundance of beneficial microorganisms, and changing soil quality for nutrient availability and abiotic conditions.

Efecto de la utilización de harina de vísceras de pollo en los parámetros productivos de lechones destetados / Effect of the use of chicken viscera meal on the productive parameters of weaned piglets / Efeito da utilização de farinha de vísceras de frango nos parâmetros produtivos de leitões desmamados

Resumen En la alimentación de cerdos el costo significativo esta influenciado por el uso de alimentos balanceados, por ende, se evaluó el uso de la harina de vísceras de pollo (HV) en lechones destetados y el efecto sobre los parámetros productivos. Se utilizó 36 lechones machos y hembras de 28 días de edad, distribuidos en tres tratamientos diferentes: T1 con pienso comercial (PC), T2 con el 50% de PC y 50% de harina de vísceras (HV), T3 con 0% PC y 100% HV. Se evaluó el consumo alimenticio, ganancia media diaria de peso, conversión alimenticia, rentabilidad, morbilidad, mortalidad, mediante la prueba de Anova y para ver que tratamiento fue significativo donde se utilizó la prueba de comparación múltiple de Tukey, por otro lado, se utilizó el algoritmo de árbol de decisión para ver que tratamiento es más rentable al utilizar todas las variables entrada. Se comprobó que existen diferencias significativas con respecto a: peso corporal, ganancia de peso, consumo de alimento, conversión alimenticia al 95% de significancia. Mediante el algoritmo de árbol de decisión el tratamiento de mayor rentabilidad es T2. En base a los resultados, la harina de vísceras de pollo puede ser utilizada al 100% en lechones destetados, pero en cuanto a la rentabilidad es T2 por su aporte en lo que respecta a producción de carne por kg y bajo costo comercial.

Abstract In pig feeding, the significant cost is influenced by the use of balanced feed, therefore, the use of chicken viscera (HV) meal in weaned piglets and the effect on productive parameters was evaluated. Thirty-six 28-day-old male and female piglets were used, distributed in three different treatments: T1 with commercial feed (PC), T2 with 50% PC and 50% viscera meal (HV), T3 with 0% PC and 100% HV. Food consumption, average daily weight gain, feed conversion, profitability, morbidity, mortality, were evaluated through the Anova test and to see which treatment was significant where Tukey's multiple comparison test was used, on the other hand, it was used the decision tree algorithm to see which treatment is more profitable when using all the input variables. It was found that there are significant differences with respect to: body weight, weight gain, feed consumption, feed conversion at 95% significance. Using the decision tree algorithm, the most profitable treatment is T2. Based on the results, chicken viscera meal can be used 100% in weaned piglets, but in terms of profitability it is T2 for its contribution in terms of meat production per kg and low commercial cost.

Resumo Na alimentação de suínos, o custo significativo é influenciado pelo uso de ração balanceada, portanto, avaliou-se o uso de farinha de vísceras de frango (HV) em leitões desmamados e o efeito sobre parâmetros produtivos. Foram utilizados 36 leitões machos e fêmeas com 28 dias de idade, distribuídos em três diferentes tratamentos: T1 com ração comercial (PC), T2 com 50% PC e 50% farinha de vísceras (HV), T3 com 0% PC e 100% HV. O consumo alimentar, ganho de peso médio diário, conversão alimentar, lucratividade, morbidade, mortalidade, foram avaliados através do teste Anova e para verificar qual tratamento foi significativo onde foi utilizado o teste de comparação múltipla de Tukey, por outro lado, foi utilizado o algoritmo de árvore de decisão para ver qual tratamento é mais lucrativo ao usar todas as variáveis ​​de entrada. Verificou-se que existem diferenças significativas com relação a: peso corporal, ganho de peso, consumo de ração, conversão alimentar a 95% de significância. Usando o algoritmo de árvore de decisão, o tratamento mais rentável é o T2. Com base nos resultados, a farinha de vísceras de frango pode ser utilizada 100% em leitões desmamados, mas em termos de rentabilidade é T2 por sua contribuição em termos de produção de carne por kg e baixo custo comercial.

Geração de energia usando biogás de aterros sanitários no Brasil: um estudo de potencial energético e viabilidade econômica em função da população / Power generation using landfill biogas in Brazil: a study of energy potential and economic viability in terms of the population

RESUMO A busca por energias alternativas que sejam renováveis está cada vez maior, assim como a preocupação com o crescente aumento da geração de resíduos pela população mundial. O aproveitamento energético do gás gerado pela decomposição dos resíduos sólidos é um caminho atrativo para a solução, de uma só vez, desses dois problemas. Com objetivo de contribuir para o desenvolvimento da geração de energia elétrica a partir de aterros sanitários no Brasil, o presente trabalho compreende uma análise de potencial energético e de viabilidade financeira dessa alternativa energética no Brasil. Para a construção das análises, utilizaram-se dados de geração de resíduos e climáticos de seis cidades brasileiras, o que permitiu a estimativa da vazão de produção de gás nos aterros de cada uma dessas localidades, a potência ótima a ser instalada em cada um desses aterros e da viabilidade econômica dessa alternativa. Os valores de custo de geração obtidos variaram entre R$ 345 e 440·MWh, sendo fortemente influenciados por fatores como população, captação de resíduos e aspectos climáticos, sendo, em geral, superiores aos valores típicos de tarifa de venda de energia no país. Isso implica uma necessidade de formulação de políticas públicas de incentivo à geração de energia a partir de resíduos sólidos urbanos no Brasil.

ABSTRACT The search for alternative and renewable sources of energies is growing, as is the concern with the growing increase in the generation of waste by the world population. The energy use of the gas generated by the decomposition of solid waste at landfills is an attractive way to solve these two problems, at once. In order to contribute to the development of electric power generation from landfills in Brazil, the present work comprises an analysis of the energy potential and financial viability of this energy alternative in the country. For the construction of the analyses, waste and climate generation data from six Brazilian cities were used, which allowed the estimation of the gas production flow in the landfills of each city, the optimum power to be installed in each of these landfills and the economic viability of this alternative. The generation cost values obtained ranged between R$ 345 and 440·MWh, being strongly influenced by factors such as population, waste capitation and climatic factors, being, in general, higher than the typical values of energy sales tariff in the country. This implies a need to formulate public policies to encourage the generation of energy from solid urban waste in Brazil.

Integrated project of a smart microgrid allied with energy management: An initiative to reduce electrical energy costs

Abstract Electricity is undoubtedly one of the most important resources in the modern world. As the demand for electric energy increases, conventional resources that are transformed into electric energy are being exhausted, generating a need to search for alternative sources, resulting in a significant increase in energy costs. This study presents an integrated project of an intelligent microgrid and energy management aimed at reducing energy costs. At the Federal University of Paraná (UFPR), electricity represents an annual cost of over BRL 13 million, which is the third largest operating expense of the university. In addition, the public education budget in Brazil has been decreased in recent years. Therefore, this study was conducted within the scope of UFPR and aimed to analyze three alternatives to reduce electric energy costs: i) demand management through an analysis of energy bills, ii) migration to the free energy market, and iii) the development of an in-house photovoltaic generation facility. A computational tool to optimize the contracted demand and simulate the annual savings with the free market and distributed generation projects was developed using Microsoft Excel. Payback, the net present value, and the internal rate of return were calculated. Finally, the economic viability of all alternatives was proven, with demand management demonstrating an economic potential of greater than BRL 500,000 per year, use of the free market saving more than BRL 300,000, and the developed in-house photovoltaic generation system achieving an economic impact of more than BRL 600,000 per year.

Feasibility Study through Grid-Connected Photovoltaic Systems in Curitiba

ABSTRACT The increase in energy demand in Brazil encourages the country to increasingly invest in generation of electric energy, where the demand for other renewable sources increases gradually because they have a lower impact on the environment. The use of Grid-Connected Photovoltaic Systems (GCPVS) is a viable solution for the country, since it presents favorable natural conditions for the use of solar energy. This study approaches the current scenario of three photovoltaic systems installed in Curitiba in 2016 and part of 2017: Green Office (GO) located in Curitiba Campus Downtown, Curitiba Campus Neoville, both of the Federal Technological University of Paraná (UTFPR), as well as a residence. By means of performance parameters, performance analysis of these systems were carried out and, in order to measure the length of time of the return of the initial investment in its installation, a study of the economic viability of these systems according to the current rate model in Brazil through economic engineering tools was carried out: Simple Payback and Discounted Payback, Net Present Value and Internal Rate of Return. Finally, the application of the saved value of electric energy bills was simulated in a bank account during the system´s lifespan.

Criação de pacas (Cuniculus paca) como alternativa de diversificação de produção e renda em Rio Branco - Acre / Pacas creation (Cuniculus paca) as production diversification of alternative and income in Rio Branco - Acre / Creación de pacas (Cuniculus paca) como alternativa de diversificación de producción y ganancia en rio Branco - Acre

Para iniciar uma atividade comercial, estudos neste segmento devem ser realizados para verificação da viabilidade econômica e financeira, analisando as oportunidades e os riscos pertinentes ao projeto. Dessa forma, a finalidade deste estudo foi analisar indicadores de viabilidade de custo-benefício dos investimentos para um projeto de criação comercial de pacas (Cuniculus paca), em Rio Branco-Acre. Para este estudo utilizou-se índices econômicos para criação de 36 matrizes e 12 reprodutores, sendo um macho para três fêmeas, em sistema intensivo de produção, considerando-se a construção do galpão com o uso de parte da matéria-prima disponível na região, mão de obra local de profissionais autônomos, assistência técnica fornecida por órgãos públicos, alimentação adquirida na propriedade, animais fornecidos pelo IBAMA, por meio de doações e/ou capturados, mão de obra familiar para criação dos animais, custo de produção dos animais, valor da carne vendida para restaurantes R$35,00/Kg, preço do prato individual comercializado pelos restaurantes, porção de 250g R$30,00/40,00 e 50,00, dependendo do restaurante. Os resultados destacaram como principais custos para a implantação da atividade, a construção das instalações, considerando-se matéria-prima e mão de obra. Além disso, constatou-se que a criação comercial de pacas pode se tornar uma alternativa viável da diversificação de produção e renda para produtores da região.

For feasibility and performance of commercial activity, we need to study for economic and financial evaluation, verification of the opportunities and risks relevant to the project. Therefore, the purpose of this study was to analyze the investment cost-benefit feasibility indicators for a commercial breeding project pacas (Cuniculus paca) in Rio Branco-Acre. For this study we used economic indices for creating arrays 36 and 12 breeders, with a male to female three in intensive production system, considering the construction of the shed with the use of the available raw material in the region hand local work of independent professionals, technical assistance provided by public agencies, gained power in the property, animals supplied by IBAMA through donations and / or captured, family labor for animal husbandry, production cost of animals, the value of meat to Restaurants will be R$35.00kg, the price of individual plate to be sold by restaurants, 250g portion of R$30.00/40.00 and 50.00, that depending on the restaurant. The results highlighted as major costs for the implementation of activity the construction of the facility, considering raw materials and labor. The results of this study found that trade creation of pacas can become a viable alternative to diversify production and income for producers in the region.

Para la viabilidad y el desempeño de una actividad comercial hay necesidad de estudios de evaluación económica y financiera, la verificación de las oportunidades y los riesgos pertinentes para el proyecto. Por lo tanto, el propósito de este estudio ha sido analizar los indicadores de viabilidad de coste/beneficio de las inversiones para un proyecto de creación comercial de pacas (Cuniculus paca) en Rio Branco-Acre. Para este estudio se utilizó los indicadores económicos para la creación de 36 matrices y 12 reproductores, siendo un macho para tres hembras, en sistema intensivo de producción, considerándose la construcción del galpón con la utilización de una parte de las materias primas disponibles en la región, la mano de obra local de profesionales autónomos, asistencia técnica proporcionada por organismos públicos, alimentación adquirida en la propiedad, animales proporcionados por IBAMA, a través de donaciones y/o capturados, mano de obra familiar para la ganadería, costo de producción de los animales, valor de la carne vendida a los restaurantes de R$ 35,00 / kg, el precio del plato individual vendido por restaurantes, porción de 250 g de R$ 30.00 / 40.00 y 50.00, dependiendo del restaurante. Los resultados destacaron como principales costos, para la implantación de la actividad, la construcción de las instalaciones, considerándose materias primas y mano de obra. Además, se encontró que la creación comercial de pacas puede convertirse en una alternativa viable de diversificación de producción y renta para los productores de la región.

Use of ground and extruded canola seeds in feed for 15-30 kg piglets / Uso de la semilla de canola molida y extrusada en la alimentación de lechones de 15-30 kg

Objective. Determine the nutritional values of ground (SCI) or extruded (SCE) canola seed and evaluate its use in the performance of piglets from 15 to 30 kg. Materials and methods. Two experimental diets with canola seed were evaluated in a digestibility trial. We used 15 barrows with an initial weight of 19.79±1.43kg, distributed in a completely randomized design. In the performance, four experimental diets were evaluated consisting of a diet with soybean oil added (RAS), one with the of addition of canola oil (RAC) and two oil-free; one with 11% SCI included and one with 6% SCE (RSCE) included. 40 commercial hybrid piglets were used that had 15.25±1.5kg initial body weight, randomly distributed, in four treatments and five replicates; two animals per experimental unit. Results. The digestible energy values for SCI and SCE were 4.197 kcal/kg and 5.234 kcal/kg, respectively. The extrusion process improved the digestibility coefficients. Piglets fed with RSCI showed less daily weight gain (DWG) and F:G ratio. Conclusion. Results suggest that SCE can be included in diets of piglets from 15 to 30 kg until 6% without negatively affecting performance.

Objetivo. Determinar los valores nutricionales de las semillas de canola integral molida (SCI) y extrusada (SCE) y evaluar su influencia sobre el desempeño de lechones de 15 a 30 kg. Material y métodos. Se evaluaron dos dietas experimentales con semilla de canola en un ensayo de digestibilidad. Fueron utilizados 15 lechones machos, castrados, con peso inicial de 19.79±1.43kg, distribuidos en un diseño completamente al azar. En el desempeño se evaluaron cuatro dietas experimentales que consistieron de una dieta con adición de aceite de soya (RAS), una con adición de aceite de canola (RAC) y otras dos exentas de aceite; siendo una con la inclusión de 11% de SCI (RSCI) y otra con la inclusión de 6% de SCE (RSCE). Fueron utilizados 40 lechones híbridos comerciales, con peso vivo medio inicial de 15.25±1.5kg, distribuidos en un diseño experimental completamente al azar, con cuatro tratamientos, cinco repeticiones; siendo dos animales por unidad experimental. Resultados. Los valores de energía digestible para SCI y SCE en base seca fueron de 4.197 kcal/kg y 5.234 kcal/kg, respectivamente. El proceso de extrusión mejoró los coeficientes de digestibilidad. Los lechones alimentados con RSCI presentaron menor ganancia de peso (GPD) y peor conversión alimentaria (CA). Conclusiones. Los resultados indicaron que la SCE puede ser incluida en la dieta de lechones de 15 a 30 kg, hasta un nivel de 6% sin afectar el desempeño.

Avaliação nutricional da glicerina vegetal semipurificada para codornas de corte / Nutritional evaluation of vegetable semi-purified glycerin of meat type quail

Foram conduzidos três experimentos com o objetivo de determinar a composição química e os valores de energia metabolizável da glicerina vegetal semipurificada e verificar o desempenho e as características de carcaça de codornas de corte alimentadas com rações contendo níveis crescentes de glicerina. No experimento 1, foram utilizadas 50 codornas, alojadas em gaiolas de metabolismo. Os tratamentos consistiram de uma ração referência e de uma ração teste contendo nível de substituição de 10% de glicerina, com cinco repetições de cinco codornas por repetição. O valor de energia metabolizável aparente corrigida para balanço de nitrogênio da glicerina foi de 3.069kcal/kg. No experimento 2, foram utilizadas 640 codornas, distribuídas em um delineamento inteiramente ao acaso, com cinco tratamentos (ração controle e níveis de glicerina = 4, 8, 12 e 16%) e quatro repetições com 32 aves em cada repetição. Não foram observadas diferenças (P>0,05) para consumo de ração e ganho de peso. A inclusão de glicerina, na fase de um a 14 dias de idade, piorou a conversão alimentar. No experimento 3, foram utilizadas 440 codornas, distribuídas em um delineamento inteiramente ao acaso, com cinco tratamentos e quatro repetições com 22 aves em cada repetição. Os tratamentos utilizados foram os mesmos do experimento 2. O consumo de ração aumentou linearmente (P<0,05) com o aumento dos níveis de glicerina, contudo o ganho de peso e a conversão alimentar não foram influenciados. Conclui-se que a glicerina semipurificada pode ser incluída nas rações das codornas, na fase de 15 a 35 dias de idade, até o nível de 16%.

Three experiments were carried out to determine the chemical composition and metabolizable energy values of vegetable semi-purified glycerin and verify the performance and carcass yeild of meat type quai, fed with diets containing increasing levels of glycerin. In the first experiment 50 quails were used, housed in metabolism cages. The treatments consisted of a reference diet and a test diet containing the replacement level of 10% glycerin, with five replications of five quails per replication. The value of apparent metabolisable energy corrected by nitrogen balance of glycerin was 3.069 kcal/kg. In the second experiment 640 quails were used, distributed in a completely randomized design, with five treatments (control diet and four levels = 4, 8, 12 and 16% of glycerin), four replications with 32 birds per replication. There were no differences (P>0.05) on feed intake and weight gain. The inclusion of glycerin (1 - 14 days of age) decrease feed:gain ratio. In the third experiment, 440 quails were used, distributed in a completely randomized design, with five treatments, with four replications with 22 birds per repetition. The treatments used were the same as the second trial. The feed intake increased linearly (P<0.05) with the increase in the levels of glycerin, however, weight gain and feed:gain ratio were not influenced. It follows that the semi-purified glycerin can be included in the diets of quail (15 - 35 days of age) in levels up to 16%.

Análise da quantidade produzida de CO2 pela bovinocultura no estado do Rio Grande do Sul / Analysis of CO2 produced from cattle culture in the state of Rio Grande do Sul, Brazil

Este trabalho tem como objetivo identificar a quantidade de gases causadores de efeito estufa emitidos anualmente pela bovinocultura no Estado do Rio Grande do Sul. A partir dos resultados, é analisada a viabilidade econômica, em termos de instalação de créditos de carbono, da instalação de biodigestores nas propriedades rurais, calculando-se a quantidade de toneladas medidas em unidades de gás carbônico, equivalentes por ano, que a adoção dessa tecnologia permitiria mitigar. Entre os resultados obtidos, tem-se que a instalação de biodigestores é viável apenas para propriedades que possuem mais de 20 animais, as quais representam 63% do rebanho bovino gaúcho, e a mitigação de 29.548,26ton equiv. CO2 ano.

The aim of this paper is to identify the amount of greenhouse gases from cattle culture in the state of Rio Grande do Sul. Thus, it was analyzed the economic viability, in terms of installation of carbon credits, of biodigesters installations on farms. It was calculated the measure of the amount of tons measured in units of carbon dioxide per year in which the use of that technology would mitigate. Among the outcomes obtained, the biodigesters installation is profitable just on farms where there are more than 20 animals. These farms represent 63% of cattle culture in Rio Grande do Sul and the mitigation 29.548,26 CO2 tons per year.

Economia na produção de helicônias no Estado do Rio de Janeiro / Economy in helicônias production in Rio de Janeiro State

A pesquisa teve como objetivo determinar, mediante o cálculo do valor presente líquido (VPL), da taxa interna de retorno (TIR) e do Payback Econômico (PBE), a viabilidade da produção de helicônias no Estado do Rio de Janeiro, bem como identificar e verificar, por meio da análise de sensibilidade, em que medida alguns fatores do sistema produtivo exercem impacto sobre a rentabilidade das regiões produtoras. Os resultados mostraram que a produção de helicônias é uma atividade lucrativa, segundo o método da TIR e considerando taxas mínimas de atratividade (TMA) de 6 por cento e 12 por cento para o cálculo do VPL. Porém, ocorrem limitações no setor de escoamento da produção, retardando a consolidação desse mercado. O percentual de perdas e o preço de venda do produto apresentaram-se como fatores determinantes sobre o tempo de retorno do investimento (PBE). Além disso, o preço de venda do produto foi a variável com maior efeito sobre a rentabilidade, seguida do valor da terra e do custo das mudas.

The purpose of the research was to determine, through the calculation of net present value (VPL), internal return rate (TIR) and Economic Payback (PBE), the viability of Heliconias production in the Rio de Janeiro State, as well as identify and verify, by means of sensitivity analysis in which extent some factors of the production system exercise impact on the profitability of the producing regions. The results showed that helicônia production is a profitable activity, according to the method of TIR and considering minimal attractiveness rates (TMA) of 6 percent and 12 percent for calculating the net present value (VPL). However, there are limitations in the sector of produce flow, delaying the consolidation of this market. The percentage of losses and the selling price of the product presented determinant factors on the time of return on investment (PBE). In addition, the selling price of the product was the variable with greater effect on profitability, followed by the land value and the seedlings cost.

Custo de produção e rentabilidade das culturas de alface, rabanete, rúcula e repolho em cultivo solteiro e consorciadas com pimentão / Production cost and profitability of lettuce, radish, arugula and cabbage sole crop and intercropped with sweet pepper

Realizou-se, o trabalho na UNESP, Jaboticabal, SP, com o objetivo de avaliar a rentabilidade das culturas de alface, rabanete, rúcula e repolho, em cultivo solteiro e consorciadas com pimentão. A determinação dos custos de produção das culturas em cultivo solteiro e em consórcio foi realizada com base na metodologia do custo operacional total (COT), com valores referentes a março de 2005. Para o cálculo da receita bruta, considerou-se o preço do setor atacadista, CEAGESP, no mês de março de 2005. Os COT das culturas de repolho, rúcula, alface e rabanete, quando consorciadas com pimentão, tiveram redução de 34,0 por cento, 24,7 por cento, 21,3 por cento e 20,8 por cento em relação aos seus respectivos cultivos solteiros. As culturas de alface e rabanete consorciadas com pimentão apresentaram aumento na receita líquida em 49,6 por cento e 13,9 por cento, respectivamente, quando comparadas com seus cultivos solteiros. A maior rentabilidade foi obtida em consórcio de pimentão com alface. A taxa de retorno e índice de lucratividade dos consórcios foram superiores aos observados nas monoculturas.

This work was carried out at UNESP, in Jaboticabal, SP, with the aim of evaluating the production cost and profitability of lettuce, radish, arugula and cabbage sole crop and intercropped with sweet pepper. The determination of the production cost was accomplished with base on the methodology of the total operational cost (TOC), in March of 2005. For the calculation of the gross revenue, the price of the wholesale sector, CEAGESP, applied in March 2005, was considered,. The TOC of the cultures cabbage, arugula, lettuce and radish when intercropped with sweet pepper had a reduction of 34.0 percent, 24.7 percent, 21.3 percent and 20.8 percent, when compared to their respective single cultivation. The cultures of lettuce and radish intercropped with sweet pepper had net revenue increase of 49.6 percent and 13.9 percent, respectively, when compared to their single cultivation. The largest profitability was obtained when sweet pepper was intercropped with lettuce. The return rate and the profitability index of the intercropping were higher than those of the single cultivation.