Several studies have expressed concerns about the effects of gene flow from transgenic herbicide‐resistant crops to their wild relatives, but no major problems have been observed. This review describes a case study in which what has been feared in transgenics regarding gene flow has actually changed biodiversity and people's lives. Nontransgenic imidazolinone‐resistant rice (IMI‐rice) cultivars increased the rice grain yield by 50% in southern Brazil. This increase was beneficial for life quality of the farmers and also improved the regional economy. However, weedy rice resistant to imidazolinone herbicides started to evolve three years after the first use of IMI‐rice cultivars. Population genetic studies indicate that the herbicide‐resistant weedy rice was mainly originated from gene flow from resistant cultivars and distributed by seed migration. The problems related with herbicide‐resistant weedy rice increased the production costs of rice that forced farmers to sell or rent their land. Gene flow from cultivated rice to weedy rice has proven to be a large agricultural, economic, and social constraint in the use of herbicide‐resistant technologies in rice. This problem must be taken into account for the development of new transgenic or nontransgenic rice technologies.
Resumo -O objetivo deste trabalho foi avaliar a eficiência bioeconômica de cordeiros F 1 Dorper x Santa Inês para produção de carne. Analisou-se o desempenho de ovinos ½ sangue Dorper x ½ sangue Santa Inês, nas fases de cria e de acabamento. A fase de produção das crias foi realizada em caatinga nativa e a fase de acabamento em confinamento. As matrizes foram suplementadas nos últimos 50 dias de prenhez e nos primeiros 30 dias de lactação. As crias foram desmamadas aos 70 dias de idade, divididas em três lotes e confinadas, alimentadas com capim-elefante (Pennisetum purpureum) ad libitum e concentrado na proporção de 1,5%, 2,5% e 3,5% do peso vivo, respectivamente. O sexo não exerceu influência sobre os pesos no nascimento, no desmame, nem sobre o ganho em peso até o desmame. Não foi observada influência do sexo sobre os pesos e os ganhos em peso aos 30 e 50 dias de confinamento. Nas fases de produção e acabamento em confinamento, os animais de nascimento simples foram superiores aos de nascimento duplo quanto a essas variáveis. Houve efeito linear significativo para peso e ganho em peso aos 30 e 50 dias de confinamento. Os três níveis de uso de concentrado foram economicamente viáveis. As margens brutas de peso vivo, por kg de cordeiro produzido, foram de R$ 0,26 kg -1 , R$ 0,30 kg -1 e R$ 0,36 kg -1 para concentrados a 1,5%, 2,5% e 3,5% do peso vivo, respectivamente. Os melhores resultados econômicos foram obtidos quando o nível de concentrado foi de 3,5% do peso vivo.Termos para indexação: ovino, cruzamento industrial, peso corporal, ganho em peso, confinamento, viabilidade econômica. Bioeconomic efficiency of F 1 Dorper x Santa Inês lambs for meet productionAbstract -The objective of this work was to evaluate bioeconomic efficiency of F 1 Dorper x Santa Inês lambs for meet production. Performance of F 1 Dorper x Santa Inês lambs in raising and fattening phases was analyzed. The production phase of lambs was realized in native pastures ("caatinga") and the finishing phase was in confinement. The ewes were supplemented during the last 50 days of pregnancy and the first 30 days of lactation. Lambs were weaned at 70 days of age, divided into three lots, confined and fed elephant grass (Pennisetum purpureum) ad libitum, and concentrate in the proportion of 1.5%, 2.5% and 3.5% of live weight, respectively. Lambs sex did not have significant influence on birth weight, as well as on weaning weight and weight gain until weaning. In production and confinement phases, lambs of single births were superior to double births ones considering these variables. Linear effect was significant for weight and for weight gain, at 30 and 50 days of confinement. The three inclusion levels of concentrate were economically viable. Gross margins of live weight for each kg of lamb produced were R$ 0.26 kg -1 , R$ 0.30 kg -1 and R$ 0.36 kg -1 of live weight to concentrates of 1.5%, 2.5% and 3.5%, respectively. The best economics results were obtained when the concentrate level was 3.5% of live weight.
The objective of this study is to estimate the production costs and profitability of corn cultivation in the setup phase of the crop-livestock-forest integration system for pasture recovery in the municipality of Pindaré-Mirim/MA, Brazil. The study was developed at the Technological Reference Unit (TRU) for the Integration of Crop-Livestock-Forest (ICLF) of Embrapa Cocais, located in the municipality of Pindaré-Mirim/MA, Brazil. Data collection occurred during the agricultural year 2015/2016. The management of the ICLF system was carried out following the molds of the "Santa Fé" technique. The cost of production was used to calculate the Total Operational Cost (TOC) and were extrapolated per hectare. For the economic analysis of corn production, three different prices were considered: (a) the price received by the producer; (b) the historical average of the last 30 months to the date of actual sale of the product; and (c) the minimum guarantee price of the federal government. The TOC was found to be US$ 1,672.72 per hectare. The economic efficiency indicators showed promising profit values, demonstrating that in this study with corn production in the 1st year, it would be possible to pay for the implementation of the ICLF system as an alternative for the recovery of degraded pasture.
Resumo O objetivo deste trabalho foi avaliar a contribuição do sistema de produção integrada de feijão-comum (PI), em comparação ao sistema de produção convencional, quanto ao uso de energia, à eficiência energética e à pegada de carbono, contabilizados desde a fabricação de insumos até a colheita de grãos nas fazendas, tendo-se excluído o transporte. Foram selecionadas quatro fazendas em Cristalina, GO, na terceira época de produção de feijão, em 2009. O sistema PI reduziu o uso médio de energia em 3,1%, em comparação ao convencional. Os resultados variaram de 22.759,9 a 25.518,4 MJ ha-1. A adubação nitrogenada com 6.584,0 MJ ha-1, as operações mecanizadas com 5.309,4 MJ ha-1 e a irrigação com 4.961,4 MJ ha-1 tiveram a maior participação quanto ao uso de energia. A eficiência energética em PI (2,16) foi superior à observada no sistema convencional (2,01). Não houve diferença significativa entre os dois sistemas quanto à pegada de carbono por hectare, mas a pegada de carbono por quilograma de feijão produzido no PI (0,301 kg CO2-eq kg-1) foi significativamente menor do que no convencional (0,325 kg CO2-eq kg-1). A melhora da eficiência da adubação nitrogenada, por meio do uso de fixação biológica de N, e a racionalização da mecanização são os componentes dos sistemas de produção que mais contribuem para a diminuição da pegada de carbono.
The objective of this paper is to verify the existence of asymmetric price transmission in the farm, wholesale and retail dry bean market in Sāo Paulo, Brazil. The dry bean market is characterised by high price volatility, mainly due to harmful interference from informal actors. Consequently, the prices being practiced at different chain levels have asymmetric transmission, which can be explained by failures in coordination, opportunistic behaviour of farmers and intermediaries, and the asymmetry of information amongst actors within the chain. Our findings confirm those of the existing literature - in situations of asymmetric price transmission, price increases at farm level are more intensely transmitted to wholesalers and retailers than price decreases. Consequently, the common bean market shows inefficiencies in price transmission along the chain, as price increases at farm level generate higher impacts on retail prices, violating the absolute form of purchasing power parity.
The patterns of consumption of food have been rapidly changing. This change has been reflecting in the increase of safer and more sustainable food consumption. Agricultural foods that are grown in Integrated Production (IP) also match the new consumer food quality patterns. In Brazil, the supply of IP certified products is still small. The objective of the present study was to evaluate the consumer perception and intention of purchasing certified beans based on the replication of the Theory of Planned Behavior (TPB). The survey was conducted in Goiania (GO), Brazil, in 2014, when 160 consumers of common beans were interviewed in a local hypermarket. Data were analyzed based on the structural equation modeling (SEM). The results revealed characteristics of consumer behavior when faced to certified beans as a hypothetical product, since they are not yet available on the market. The results indicated that the theoretical model based on the TPB used to explain the intention behavior of purchasing certified beans resulted in reasonable fit indices, but with only some of the relations among constructs were consistent with the theory. Thus, the results showed that the proposed model was adequate for explaining the consumer behavior towards the IP certified beans purchasing. As exceptions, one can refer the constructs subjective norms and perceived behavioral control toward the intention of purchasing.
Resumo: Objetivou-se descrever os estabelecimentos agropecuários de produção orgânica em comparação com os estabelecimentos convencionais no estado de Santa Catarina, Brasil. A comparação foi feita utilizando-se os microdados do Censo Agropecuário de 2006. A análise de qui-quadrado efetuada com os dados mostra que somente num parâmetro não há diferença entre agricultores convencionais e orgânicos. O tamanho da família com até 2 pessoas é igual entre convencionais e orgânicos. Encontraram-se diferenças estatísticas dentre convencionais e orgânicos nos seguintes parâmetros: sexo, domicílio, renda média mensal, propriedade da terra, uso do crédito agrícola, associação a cooperativas, uso da área pelos estabelecimentos, escolaridade e anos de experiência. Palavras-chave: Dados regionais; Medidas econômicas regionais; Renda.Abstract: This paper makes a comparison between the conventional and the organic farms of the state of Santa Catarina, Brazil. The comparison was made using the microdata from the 2006 Agricultural Census. The chi-square analysis showed that only one parameter does not differentiate between conventional and organic farmers: family size with up to 2 people. In this parameter there are no statistical differences between conventional and organic. There were statistical differences between conventional and organic farms in the following parameters: sex, domicile, average monthly income, land ownership, use of agricultural credit, membership at cooperatives, use of the area by establishments, schooling and years of experience.
No sistema plantio direto (SPD), a rotação de culturas é requisito imprescindível. Entretanto, ainda existem questionamentos sobre a economicidade do sistema, principalmente em áreas agrícolas irrigadas. O objetivo deste trabalho foi determinar o efeito de rotações de culturas e manejo do solo na produtividade de grãos de milho e feijoeiro comum e no rendimento econômico do sistema. O delineamento experimental foi o de blocos ao acaso, em parcelas divididas, com seis repetições. Os tratamentos incluíram três sistemas de manejo do solo (parcelas): P 1 = plantio direto no verão seguido anualmente de um preparo com arado no inverno; P 2 = plantio direto seguido bienalmente de um preparo com arado no inverno; P 3 = plantio direto contínuo; incluíram-se, também, três rotações de culturas (subparcelas): R 1 = Milho/feijão/milho/feijão; R 2 = Milheto/feijão/milho/feijão; R 3 = Soja/ feijão/milho/feijão. No final da rotação, repetiram-se as mesmas rotações na mesma área, havendo, portanto, dois ciclos de rotação. O sistema plantio direto proporcionou a menor produtividade de grãos para as culturas do milho e do feijoeiro comum. O milheto proporciona a maior produtividade de grãos do feijoeiro comum no SPD. Todas as rotações testadas proporcionam rendimento econômico positivo, ou seja, são economicamente viáveis. Dentre as opções testadas, a rotação de culturas milheto/feijoeiro comum/milho/feijoeiro comum, no SPD, é a que proporciona maior rentabilidade econômica.
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