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1.
J Econ Entomol ; 108(3): 849-57, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26470203

RESUMEN

Food production is challenged by changes in climate and land use and expanding human population growth. Proper pollination can increase the production and quality of fruit, nut, oil, and fiber crops. We reviewed crop dependence on pollinators and estimated the economic value of pollination per year for each crop in Brazil. We analyzed 141 crops and found that 85 depend on pollinators. Almost one-third of these crops have an essential or great dependence on pollinators. The economic contribution of pollinators totals ∼30% (∼US$12 billion) of the total annual agricultural income of the dependent crops (totalizing almost US$45 billion). However, half of these figures includes soybean crop (US$5.7 billion of pollinators' contribution and US$22 billion of annual income). Soybean was considered as having a modest dependence on pollinators, but this remains controversial because pollinator dependence might vary among different varieties cultivated in Brazil. Moreover, we have no information about pollinator dependence regarding some important crops, showing the urgent need for basic research into reproductive biology and pollination ecology.


Asunto(s)
Abejas/fisiología , Productos Agrícolas/economía , Productos Agrícolas/fisiología , Polinización , Animales , Brasil , Productos Agrícolas/crecimiento & desarrollo , Glycine max/economía , Glycine max/crecimiento & desarrollo , Glycine max/fisiología
2.
Food Chem ; 153: 207-15, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-24491722

RESUMEN

This article describes the nutrient and elemental composition, including residues of herbicides and pesticides, of 31 soybean batches from Iowa, USA. The soy samples were grouped into three different categories: (i) genetically modified, glyphosate-tolerant soy (GM-soy); (ii) unmodified soy cultivated using a conventional "chemical" cultivation regime; and (iii) unmodified soy cultivated using an organic cultivation regime. Organic soybeans showed the healthiest nutritional profile with more sugars, such as glucose, fructose, sucrose and maltose, significantly more total protein, zinc and less fibre than both conventional and GM-soy. Organic soybeans also contained less total saturated fat and total omega-6 fatty acids than both conventional and GM-soy. GM-soy contained high residues of glyphosate and AMPA (mean 3.3 and 5.7 mg/kg, respectively). Conventional and organic soybean batches contained none of these agrochemicals. Using 35 different nutritional and elemental variables to characterise each soy sample, we were able to discriminate GM, conventional and organic soybeans without exception, demonstrating "substantial non-equivalence" in compositional characteristics for 'ready-to-market' soybeans.


Asunto(s)
Alimentos Modificados Genéticamente , Alimentos Orgánicos/análisis , Glycine max/química , Glicina/análogos & derivados , Herbicidas/análisis , Residuos de Plaguicidas/análisis , Plantas Modificadas Genéticamente/química , Carbohidratos/análisis , Alimentos Modificados Genéticamente/economía , Alimentos Orgánicos/economía , Glicina/análisis , Evaluación Nutricional , Plantas Modificadas Genéticamente/genética , Proteínas de Soja/análisis , Glycine max/economía , Glycine max/genética , Zinc/análisis , Glifosato
3.
Food Nutr Bull ; 35(4): 440-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25639129

RESUMEN

BACKGROUND: The global economic crisis in 2007/08 resulted in higher food prices, which increased household food expenditures while worsening the quantity and quality of food consumed, potentially leading to child undernutrition. OBJECTIVE: To characterize the relationship of the mean proportions of household expenditures on strategic foods with the prevalence of undernutrition (high stunting, wasting, and underweight) among children under 2 years of age in Indonesia. METHODS: The study used data from 437 districts from two nationally representative surveys conducted in 2007, the National Socioeconomic Survey (Susenas) and the Basic Health Research (Riskesdas). RESULTS: A higher mean proportion of household expenditure on soybeans was significantly associated with lower odds (3rd vs. 1st tertile) of prevalence of high wasting (OR, 0.51; 95% CI, 0.28 to 0.94; p =.031) and high underweight (OR, 0.09; 95% CI, 0.03 to 0.28; p < .0001). A lower mean proportion of household expenditure on sugar and cooking oil was significantly associated with lower odds of prevalence of high wasting (OR, 2.41; 95% CI, 1.37 to 4.23; p = .002) and high underweight (2nd vs. 1st tertile) (OR, 2.38; 95% CI, 1.05 to 5.41; p = .039). CONCLUSIONS: Among all strategic foods, a higher proportion of household expenditure on soybeans and a lower proportion of household expenditure on sugar and cooking oil are associated with lower odds of high wasting and underweight prevalence among children 0 to 23 months of age. The results indicate the need for promotion of consumption of fermented soybeans and education aiming at decreasing expenditure on sugar and cooking oil to increase consumption of more nutritious foods.


Asunto(s)
Alimentos/economía , Desnutrición/epidemiología , Presupuestos , Carbohidratos/economía , Costos y Análisis de Costo , Grasas Insaturadas en la Dieta/economía , Composición Familiar , Humanos , Indonesia/epidemiología , Lactante , Recién Nacido , Valor Nutritivo , Oportunidad Relativa , Glycine max/economía , Delgadez/epidemiología
4.
J Econ Entomol ; 106(4): 1676-83, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24020281

RESUMEN

ABSTRACT Since its discovery in the United States, the invasive plataspid Megacopta cribraria (F.) (Hemiptera: Plataspidae) has infested soybean [Glycine max (L.) Merrill] fields in often alarming numbers in parts of the southeastern United States. Although a known feeder on soybean, reports of its pest status in its native Asian range are conflicting, and little information exists documenting its impact on soybean yields. Our objective was to examine the relationship between M. cribraria density and soybean yield loss. M. cribraria adults and nymphs were confined to small soybean plots by using walk-in field cages from late vegetative stage to harvest in 2011 and 2012. Adults (0, 5, or 25 per plant) were added at late vegetative stages, and their progeny were allowed to complete a full generation within the caged plots. Densities reached as high as 182.5 +/- 23.1 (SEM) nymphs and adults per plant, and soybean yield was reduced by as much as 59.6% at the highest density treatment. The yield components seeds per pod and individual seed weight were reduced as M. cribraria densities increased, but pods per plant and protein and oil content were not affected. Preliminary economic injury level curves for a range of grain prices and management costs were calculated based on 2012 yield loss data combined with population monitoring. M. cribraria is capable of causing severe reductions in soybean yields at densities that are relevant within its invasive U.S. range.


Asunto(s)
Glycine max/crecimiento & desarrollo , Heterópteros/fisiología , Animales , Productos Agrícolas/economía , Productos Agrícolas/crecimiento & desarrollo , Conducta Alimentaria , Cadena Alimentaria , Heterópteros/crecimiento & desarrollo , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Densidad de Población , South Carolina , Glycine max/economía
5.
Philos Trans R Soc Lond B Biol Sci ; 368(1619): 20120160, 2013 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-23610168

RESUMEN

Land-use regulations are a critical component of forest governance and conservation strategies, but their effectiveness in shaping landholder behaviour is poorly understood. We conducted a spatial and temporal analysis of the Brazilian Forest Code (BFC) to understand the patterns of regulatory compliance over time and across changes in the policy, and the implications of these compliance patterns for the perceived costs to landholders and environmental performance of agricultural landscapes in the southern Amazon state of Mato Grosso. Landholdings tended to remain in compliance or not according to their status at the beginning of the study period. The perceived economic burden of BFC compliance on soya bean and beef producers (US$3-5.6 billion in net present value of the land) may in part explain the massive, successful campaign launched by the farm lobby to change the BFC. The ecological benefits of compliance (e.g. greater connectivity and carbon) with the BFC are diffuse and do not compete effectively with the economic benefits of non-compliance that are perceived by landholders. Volatile regulation of land-use decisions that affect billions in economic rent that could be captured is an inadequate forest governance instrument; effectiveness of such regulations may increase when implemented in tandem with positive incentives for forest conservation.


Asunto(s)
Agricultura/economía , Conservación de los Recursos Naturales/economía , Política Ambiental , Agricultura Forestal/legislación & jurisprudencia , Agricultura/legislación & jurisprudencia , Animales , Brasil , Carbono/análisis , Bovinos , Simulación por Computador , Conservación de los Recursos Naturales/legislación & jurisprudencia , Ecosistema , Agricultura Forestal/economía , Carne/economía , Glycine max/economía , Análisis Espacial , Árboles
7.
Biotechnol Bioeng ; 109(4): 1083-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22095526

RESUMEN

With the aim of understanding the contribution of enzymes to the cost of lignocellulosic biofuels, we constructed a techno-economic model for the production of fungal cellulases. We found that the cost of producing enzymes was much higher than that commonly assumed in the literature. For example, the cost contribution of enzymes to ethanol produced by the conversion of corn stover was found to be $0.68/gal if the sugars in the biomass could be converted at maximum theoretical yields, and $1.47/gal if the yields were based on saccharification and fermentation yields that have been previously reported in the scientific literature. We performed a sensitivity analysis to study the effect of feedstock prices and fermentation times on the cost contribution of enzymes to ethanol price. We conclude that a significant effort is still required to lower the contribution of enzymes to biofuel production costs.


Asunto(s)
Técnicas de Cultivo Celular por Lotes/economía , Biocombustibles/economía , Celulasa/economía , Etanol/economía , Proteínas Fúngicas/economía , Lignina/economía , Modelos Económicos , Benchmarking , Gastos de Capital , Carbohidratos , Costos y Análisis de Costo , Etanol/metabolismo , Fermentación , Lignina/metabolismo , Populus , Glycine max/economía , Trichoderma/enzimología , Madera/economía , Zea mays/economía
10.
Pest Manag Sci ; 67(2): 170-4, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20981726

RESUMEN

BACKGROUND: Defoliation by Anticarsia gemmatalis (Hübner), Pseudoplusia includens (Walker), Spodoptera eridania (Cramer), S. cosmioides (Walker) and S. frugiperda (JE Smith) (Lepidoptera: Noctuidae) was evaluated in four soybean genotypes. A multiple-species economic threshold (ET), based upon the species' feeding capacity, is proposed with the aim of improving growers' management decisions on when to initiate control measures for the species complex. RESULTS: Consumption by A. gemmatalis, S. cosmioides or S. eridania on different genotypes was similar. The highest consumption of P. includens was 92.7 cm(2) on Codetec 219RR; that of S. frugiperda was 118 cm(2) on Codetec 219RR and 115.1 cm(2) on MSoy 8787RR. The insect injury equivalent for S. cosmoides, calculated on the basis of insect consumption, was double the standard consumption by A. gemmatalis, and statistically different from the other species tested, which were similar to each other. CONCLUSIONS: As S. cosmioides always defoliated nearly twice the leaf area of the other species, the injury equivalent would be 2 for this lepidopteran species and 1 for the other species. The recommended multiple-species ET to trigger the beginning of insect control would then be 20 insect equivalents per linear metre.


Asunto(s)
Glycine max/parasitología , Control de Insectos/economía , Lepidópteros/fisiología , Enfermedades de las Plantas/parasitología , Animales , Genotipo , Control de Insectos/métodos , Larva/crecimiento & desarrollo , Larva/fisiología , Lepidópteros/crecimiento & desarrollo , Glycine max/economía , Glycine max/genética
11.
Sociol Q ; 51(3): 511-36, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20607926

RESUMEN

This article draws on world-system theorizing to explore the relationship between deforestation and the vertical flow of soybean exports from less-developed nations to more-developed nations as a specific form of ecologically unequal exchange. Despite overwhelming case-study research exploring soybean-deforestation dynamics in less-developed countries, the current literature lacks any cross-national investigation of this trend. Ordinary least squares regression is used to examine whether soybean exports are associated with deforestation and if the magnitude of this relationship varies by region. Overall, the findings confirm the proposed hypotheses and suggest that having a comparative advantage in soybean production is not a viable development strategy.


Asunto(s)
Comercio , Conservación de los Recursos Naturales , Abastecimiento de Alimentos , Agricultura Forestal , Glycine max , Agricultura/economía , Agricultura/educación , Agricultura/historia , Comercio/economía , Comercio/educación , Comercio/historia , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/historia , Abastecimiento de Alimentos/economía , Abastecimiento de Alimentos/historia , Agricultura Forestal/economía , Agricultura Forestal/historia , Historia del Siglo XX , Factores Socioeconómicos , Glycine max/economía , Glycine max/historia
12.
Bull Math Biol ; 71(6): 1463-81, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19267163

RESUMEN

The biological pest control in agriculture, an environment-friendly practice, maintains the density of pests below an economic injury level by releasing a suitable quantity of their natural enemies. This work proposes a multi-objective numerical solution to biological pest control for soybean crops, considering both the cost of application of the control action and the cost of economic damages. The system model is nonlinear with impulsive control dynamics, in order to cope more effectively with the actual control action to be applied, which should be performed in a finite number of discrete time instants. The dynamic optimization problem is solved using the NSGA-II, a fast and trustworthy multi-objective genetic algorithm. The results suggest a dual pest control policy, in which the relative price of control action versus the associated additional harvest yield determines the usage of either a low control action strategy or a higher one.


Asunto(s)
Evolución Biológica , Productos Agrícolas/economía , Glycine max/economía , Modelos Biológicos , Control Biológico de Vectores/economía , Control Biológico de Vectores/métodos , Algoritmos , Animales , Análisis Costo-Beneficio/métodos , Insectos , Dinámicas no Lineales , Dinámica Poblacional , Conducta Predatoria
13.
Proc Natl Acad Sci U S A ; 105(51): 20552-7, 2008 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-19075234

RESUMEN

Increased demand for corn grain as an ethanol feedstock is altering U.S. agricultural landscapes and the ecosystem services they provide. From 2006 to 2007, corn acreage increased 19% nationally, resulting in reduced crop diversity in many areas. Biological control of insects is an ecosystem service that is strongly influenced by local landscape structure. Here, we estimate the value of natural biological control of the soybean aphid, a major pest in agricultural landscapes, and the economic impacts of reduced biocontrol caused by increased corn production in 4 U.S. states (Iowa, Michigan, Minnesota, and Wisconsin). For producers who use an integrated pest management strategy including insecticides as needed, natural suppression of soybean aphid in soybean is worth an average of $33 ha(-1). At 2007-2008 prices these services are worth at least $239 million y(-1) in these 4 states. Recent biofuel-driven growth in corn planting results in lower landscape diversity, altering the supply of aphid natural enemies to soybean fields and reducing biocontrol services by 24%. This loss of biocontrol services cost soybean producers in these states an estimated $58 million y(-1) in reduced yield and increased pesticide use. For producers who rely solely on biological control, the value of lost services is much greater. These findings from a single pest in 1 crop suggest that the value of biocontrol services to the U.S. economy may be underestimated. Furthermore, we suggest that development of cellulosic ethanol production processes that use a variety of feedstocks could foster increased diversity in agricultural landscapes and enhance arthropod-mediated ecosystem services.


Asunto(s)
Productos Agrícolas/economía , Fuentes Generadoras de Energía , Control Biológico de Vectores/economía , Zea mays , Economía/tendencias , Ecosistema , Etanol , Glycine max/economía , Estados Unidos
14.
Anal Bioanal Chem ; 392(3): 395-404, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18668229

RESUMEN

Samples of rice from Mexican and USA retail stores were analyzed for the presence of transgenic (GM) events using real-time PCR. In screening for the CaMV35S promoter sequence (35SP), positive results were found in 49 and 35% of the Mexican and American samples, respectively. In further investigations in Mexican samples, 43% were positive for P35S::bar, with two above the quantifiable limit; these were 0.07% and 0.05% GMO. Fourteen out of the sixteen positive samples were labeled as imported from the USA. In testing samples bought in American retail shops, 24% showed positive results, all below the quantifiable range. It could be deduced that P35S::bar positive samples were Liberty Link(R) (LL) rice. In distinguishing between LL601 and LL62, end-point PCR was used, corroborating the P35S::bar amplicon length difference of these events. LL62 was found in one rice sample purchased in Mexico and two in the USA samples. Its presence was verified with the 35S terminator sequence. All other LL positive samples contained LL601. None of the samples analyzed showed the presence of Bt63 rice. The LL rice varieties found have been identified as not being commercially cultivated, and so their presence requires further investigation. 35SP was also present in samples which did not have any LL rice. Maize sequences could not be detected in any of the samples; however, soybean DNA was found in Mexican and USA rice samples. The Roundup Ready(R) trait was detected in trace amounts in 16 and 6% of the rice samples bought in Mexico and the USA, respectively. Real-time PCR was shown to be the method of choice for the sensitive and rapid screening of commodities and retail samples for the detection of GM and other contamination.


Asunto(s)
Comercio , Análisis de los Alimentos/métodos , Glycine max/genética , Oryza/genética , Plantas Modificadas Genéticamente/genética , Reacción en Cadena de la Polimerasa/métodos , Caulimovirus/genética , México , Oryza/clasificación , Oryza/economía , Regiones Promotoras Genéticas/genética , Glycine max/economía , Factores de Tiempo , Estados Unidos
18.
Säo Paulo; s.n; 2002. 262 p. ilus, tab, graf.
Tesis en Portugués | LILACS | ID: lil-317086

RESUMEN

O objetivo deste estudo é analisar alguns constrangimentos para modificar o padräo de dieta e comportamento alimentar necessários à prevençäo dos efeitos deletérios da transiçäo nutricional. O aspecto aplicado do trabalho é a abordagem do estudo de caso do "leite" e "iogurte" de soja. Estes produtos foram enfocados como veículos do valor "saúde" na alimentaçäo e como base de programa alimentar. Foram obtidos indicativos de que programas alimentares baseados no "leite" e "iogurte" de soja podem obter importantes resultados sob critérios de custo/benefício. Por outro lado estes produtos podem ocupar um vantajosa posiçäo de mercado frente a outros produtos similares, devido à existência de condições...


Asunto(s)
Animales , Ratas , Sustitutos de la Leche Humana , Glycine max/economía , Glycine max/metabolismo , Evaluación Nutricional , Política Nutricional , Yogur , Análisis de los Alimentos/métodos , Bioensayo , Muestras de Alimentos
19.
Poult Sci ; 76(9): 1256-63, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9276888

RESUMEN

An experiment was conducted to determine the effect of feeding method (constant vs variable) and method of formulation (lysine vs protein) on the performance and profits of first cycle, phase 2 DeKalb Delta hens from 40 to 52 wk of age as influenced by egg and feed prices. Treatments 1 to 5 were formulated based on lysine to contain 0.65 to 0.81% TSAA and fed continuously regardless of feed consumption (constant feeding). Treatments 6 to 10 and 11 to 15 were formulated based on lysine to supply 570 to 650 mg TSAA and protein to supply 580 to 660 mg TSAA per hen per d, respectively, and fed based on feed intake. Dietary TSAA level had no overall significant effect on feed consumption, egg production, egg weight, mortality, or body weight. Hens fed diets using the constant method of feeding had significantly higher egg production, egg weight, egg specific gravity, and body weight than hens fed diets formulated based on lysine or protein using the variable method of feeding. When the treatments in the two variable feeding methods were compared, feed consumption was significantly higher for hens fed diets formulated based on protein whereas egg production, egg weight, egg specific gravity, and body weight were not different. It was concluded that method of formulation (lysine vs protein) and TSAA levels required for maximum profits can vary from at least 570 to 821 mg per hen per d depending upon energy and protein cost.


Asunto(s)
Alimentación Animal/normas , Crianza de Animales Domésticos/métodos , Pollos/fisiología , Dieta/veterinaria , Proteínas en la Dieta/farmacología , Lisina/farmacología , Modelos Econométricos , Alimentación Animal/economía , Animales , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Pollos/crecimiento & desarrollo , Dieta/economía , Proteínas en la Dieta/administración & dosificación , Ingestión de Alimentos/fisiología , Huevos , Femenino , Alimentos Formulados/economía , Alimentos Formulados/normas , Modelos Lineales , Lisina/administración & dosificación , Oviposición/efectos de los fármacos , Oviposición/fisiología , Distribución Aleatoria , Glycine max/economía , Glycine max/normas , Zea mays/economía , Zea mays/normas
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