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Registros recuperados: 71
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A Regional Analysis of Maize Biological Diversity in Southeastern Guanajuato, Mexico AgEcon
Gomez, Jose Alfonso Aguirre; Bellon, Mauricio R.; Smale, Melinda.
Four environments with contrasting potential for agricultural productivity and infrastructure development were identified in Guanajuato State, Mexico, to test hypotheses about the relationship of maize biological diversity to the region's potential for agricultural productivity and infrastructure development. Samples of all types of maize grown by a random sample of farmers were collected from each environment. The maize samples were classified by race, racial mixture, or type of 'creolized' or improved variety. Landraces were the dominant maize class in all four environments; the use of improved varieties was negligible. Several diversity indices were calculated, and no statistically significant differences were apparent between the environments with the...
Tipo: Working or Discussion Paper Palavras-chave: Crop Production/Industries.
Ano: 1998 URL: http://purl.umn.edu/7671
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AGRI-ENVIRONMENTAL POLICIES IN A TRANSITIONAL ECONOMY: THE VALUE OF AGRICULTURAL BIODIVERSITY IN HUNGARIAN HOME GARDENS AgEcon
Birol, Ekin; Smale, Melinda; Gyovai, Agnes.
Agricultural biodiversity is an environmental resource. Much of the agricultural biodiversity remaining in situ today is found on the semi-subsistence farms of poorer countries and the small-scale farms or home gardens of more industrialized nations. The traditional small farms of Hungary are labelled "home gardens" as a reflection of their institutional identity during the collectivisation period. Homesteads managed with family labor, they continue to serve essential food security and diet quality functions during economic transition. Home gardens contribute to the preservation of rural settlements and cultural heritage, and they contain relatively high levels of several components of agricultural biodiversity. The role of home gardens in the...
Tipo: Working or Discussion Paper Palavras-chave: Agricultural biodiversity; In situ conservation; Choice experiment method; Hungary; Home garden; Agricultural and Food Policy; Crop Production/Industries; Environmental Economics and Policy.
Ano: 2004 URL: http://purl.umn.edu/60331
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Betting on cotton: Potential payoffs and economic risks of adopting transgenic cotton in West Africa AgEcon
Falck-Zepeda, Jose Benjamin; Horna, J. Daniela; Smale, Melinda.
Cotton is the largest source of export receipts in several West African nations where yields are declining and pesticide use is rising. Although there may be payoffs to introducing genetically modified Bt (Bacillus thurigiensis) cotton, limited information is available to predict its potential economic impact and there is uncertainty about its performance. Recognizing these constraints, we use an economic surplus model augmented with stochastic simulation to estimate ex ante the impact and distribution of benefits from Bt cotton. We consider the effects of adoption on both yields and abating crop damage, and offer scenarios depicting the policy options faced by West African stakeholders. The findings indicate that although the total net benefits of...
Tipo: Journal Article Palavras-chave: Crop biotechnology; Bt cotton; Economic surplus model; West Africa; Agricultural development; Risk; Crop Production/Industries.
Ano: 2008 URL: http://purl.umn.edu/56962
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Breeder Demand for and Utilisation of Wheat Genetic Resources in Australia AgEcon
Brennan, John P.; Godden, David P.; Smale, Melinda; Meng, Erika C.H..
As part of an ACIAR-funded project on genetic diversity in wheat in Australia and China, Australian wheat breeders were surveyed to assess the importance of genetic diversity to breeders. This paper reports the findings of that survey, and identifies the key issues that concern wheat breeders. The issues addressed include the breeders’ attitude to diversity and the diversity available in their current gene pool. The sources of materials that breeders use to maintain and/or increase diversity in their programs are identified, and ways in which diversity influences breeding decisions are also examined. More importantly from the policy view point, survey responses identify changes over time in the environment in which breeders operate that affect the extent...
Tipo: Presentation Palavras-chave: Genetic/diversity/wheat/breeder/survey; Crop Production/Industries.
Ano: 1999 URL: http://purl.umn.edu/123776
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Combining revealed and stated preference methods to assess the private value of agrobiodiversity in Hungarian home gardens AgEcon
Birol, Ekin; Kontoleon, Andreas; Smale, Melinda.
Hungarian home gardens are small-scale farms managed by farm households using traditional management practices and family labor. They generate private benefits for farmers by enhancing diet quality and providing food when costs of transacting in local markets are high. Home gardens also generate public benefits for society by supporting long-term productivity advances in agriculture. In this paper, we estimate the private value to farmers of agrobiodiversity in home gardens. Building on the approach presented in EPTD Discussion Paper 117 (2004), we combine a stated preference approach (a choice experiment model) and a revealed preference approach (a discrete-choice, farm household model). Both models are based on random utility theory. To combine the...
Tipo: Report Palavras-chave: Home gardens; Small-scale farmers; Diet quality; Agricultural productivity; Agrobiodiversity; Household surveys; Private value; Choice experiment model; Farm household model; Revealed and stated preference methods; Biodiversity; Crop Production/Industries.
Ano: 2006 URL: http://purl.umn.edu/55415
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Comparing Farm and Village-Level Determinant of Millet Diversity in Marginal Environments of India: The Context of Seed Systems AgEcon
Nagarajan, Latha; Smale, Melinda; Glewwe, Paul.
The purpose of the research paper is to characterize biological diversity related to millets in the semi-arid regions of India at various spatial scales of analysis (e.g., farm household versus community levels) and place that evidence in a broader seed systems (includes both formal and informal) context. An important finding of this research is that producer access to millet genetic resources is affected by the extent to which seed is traded via formal markets or through other social institutions, along with farm and household characteristics. Findings also underscore the need for an enhanced theoretical understanding of local seed markets in analyzing crop variety choices and the diversity of materials grown in less favored environments.
Tipo: Working or Discussion Paper Palavras-chave: Millet diversity; Seed systems; Local markets; Crop diversity; Biological diversity; Crop Production/Industries.
Ano: 2005 URL: http://purl.umn.edu/59235
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CROP BIOTECHNOLOGY FOR AFRICA: WHO WILL GAIN FROM BT MAIZE IN KENYA? AgEcon
Owuor, George; Smale, Melinda; De Groote, Hugo.
Bt maize in Kenya is promising biotechnology innovation for poor households. Econometric prediction from a trait-based model of variety adoption indicates that the choice of host variety has equity and efficiency implications related to heterogeneity in maize growing environments and pest pressures, as well as the differences among farm households in terms of wealth, income, and market access.
Tipo: Conference Paper or Presentation Palavras-chave: Maize; Bt; Adoption; Area allocation; Crop Production/Industries; Research and Development/Tech Change/Emerging Technologies.
Ano: 2004 URL: http://purl.umn.edu/20379
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Cultural Endowments, Institutional Renovation and Technical Innovation: The "Groupements Naam" of Yatenga, Burkina Faso AgEcon
Smale, Melinda; Ruttan, Vernon W..
Tipo: Working or Discussion Paper Palavras-chave: Institutional and Behavioral Economics.
Ano: 1994 URL: http://purl.umn.edu/12983
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Demand for Maize Hybrids, Seed Subsidies, and Seed Decisionmakers in Zambia. AgEcon
Smale, Melinda; Mason, Nicole M..
The successful development and diffusion of improved maize seed in Zambia during the 1970s–80s was a major achievement of African agriculture but was predicated on a government commitment to parastatal grain and seed marketing, the provision of services to maize growers, and a pan-territorial pricing scheme that was fiscally unsustainable. Declining maize output when this system was dismantled contributed to the reinstatement in 2002 of subsidies for maize seed and fertilizer through the Fertilizer and Farmer Input Support Programs (FISP). In the meantime, seed liberalization has led to an array of new, improved maize varieties, most of which are hybrids. This analysis explores the determinants of demand for first-generation (F1) hybrid maize seed in...
Tipo: Working Paper Palavras-chave: Zambia; Maize; Seed subsidies; Agricultural and Food Policy; Food Security and Poverty.
Ano: 2012 URL: http://purl.umn.edu/123555
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DETERMINANTS OF CEREAL DIVERSITY IN COMMUNITIES AND ON HOUSEHOLD FARMS OF THE NORTHERN ETHIOPIAN HIGHLANDS AgEcon
Benin, Samuel; Gebremedhin, Berhanu; Smale, Melinda; Pender, John L.; Ehui, Simeon K..
On farm conservation of crop diversity poses obvious policy challenges in terms of the design of appropriate incentive mechanisms and possible trade-offs between conservation and productivity. This paper compares factors explaining the inter-specific diversity (diversity among species) and infra-specific diversity (diversity among varieties within a species) of cereal crops grown in communities and on individual farms in the northern Ethiopian highlands. Using named varieties and ecological indices of spatial diversity (richness, evenness, and inverse dominance), we find that a combination of factors related to the agro-ecology of a community, its access to markets, and the characteristics of its households and farms significantly affect both the inter-...
Tipo: Working or Discussion Paper Palavras-chave: Household Farms; Communities; Ethiopia; Agrobiodiversity; On Farm Conservation; Crop Production/Industries.
Ano: 2003 URL: http://purl.umn.edu/16101
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Determinants of social capital formation in rural Uganda: Implications for group-based agricultural extension approaches AgEcon
Katungi, Enid; Machethe, Charles Lepepeule; Smale, Melinda.
Although social capital is a potentially important asset for poverty reduction in developing economies, there has been little analysis of factors affecting its formation in developing countries such as Uganda. This paper analyzes what influences households to join local organizations and the intensity of social networks in central Uganda. Social networks were disaggregated by major activity to gain insight into household access, and the interaction between local organizations and social networks was examined. Probit and ordered probit models were estimated to identify what led households to participate in organizations and the intensity of participation. A negative binomial model was applied to analyze the household intensity of social networks. The...
Tipo: Journal Article Palavras-chave: Social capital; Group based extension approaches; Uganda; Teaching/Communication/Extension/Profession.
Ano: 2007 URL: http://purl.umn.edu/57016
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Does Household Headship Affect Demand for Hybrid Maize Seed in Kenya? An Exploratory Analysis Based on 2010 Survey Data AgEcon
Smale, Melinda.
Women are central to food production and maize is a dominant food staple in Sub-Saharan Africa, but published gender analyses of hybrid seed use in Sub-Saharan Africa are uncommon. Building on previous work, this paper tests the effects of headship definitions on hybrid seed use and explores the variation between male- and female-headed households and among female-headed households in Kenya. Analysis is based on survey data collected by Tegemeo Institute of Egerton College during the 2009-10 cropping season.
Tipo: Working Paper Palavras-chave: Maize; Seed; Kenya; Household headship; Agricultural and Food Policy; Consumer/Household Economics; Crop Production/Industries; Food Security and Poverty.
Ano: 2011 URL: http://purl.umn.edu/118475
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Farmer Management of Maize Diversity in the Central Valleys of Oaxaca, Mexico: CIMMYT/INIFAP 1998 Baseline Socioeconomic Survey AgEcon
Smale, Melinda; Aguirre, Alfonso; Bellon, Mauricio R.; Mendoza, Jorge; Rosas, Irma Manuel.
Tipo: Working or Discussion Paper Palavras-chave: Crop Production/Industries.
Ano: 1999 URL: http://purl.umn.edu/7689
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Farmer management of production risk on degraded lands: the role of wheat genetic diversity in Tigray Region, Ethiopia AgEcon
Di Falco, Salvatore; Chavas, Jean-Paul; Smale, Melinda.
This paper investigates the effects of wheat genetic diversity and land degradation on risk and agricultural productivity in less favored production environments of a developing agricultural economy. Drawing production data from household survey conducted in the highlands of Ethiopia, we estimate a stochastic production function to evaluate the effects of variety richness, land degradation, and their interaction on the mean and the variance of wheat yield. Ethiopia is a centre of diversity for durum wheat and farmers manage complex variety mixtures on multiple plots. Econometric evidence shows that variety richness increases farm productivity. Variety richness also reduces yield variability but only for high levels of genetic diversity. Simulations with...
Tipo: Report Palavras-chave: Land degradation; Wheat production; Productivity; Risk; Genetic diversity; Household surveys; Biodiversity; Stochastic analysis; Crop Production/Industries; Risk and Uncertainty.
Ano: 2006 URL: http://purl.umn.edu/55417
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Farmer Preferences for Milpa Diversity and Genetically Modified Maize in Mexico: A Latent Class Approach AgEcon
Birol, Ekin; Villalba, Eric Rayn; Smale, Melinda.
Maize, the second most globally important staple crop after wheat, originated in Mexico, where it is typically grown as part of a set of associated crops and practices called the milpa system. This ancient mode of production is practiced today in ways that vary by cultural context and agro-environment. Milpas generate private economic value, in terms of food security, diet quality and livelihoods, for the two-million farm households who manage them. Furthermore, milpas generate public economic value by conserving agrobiodiversity, especially that of maize landraces, which have the potential to contribute unique traits needed by plant breeders for future crop improvement. In this way, milpas contribute to global food security in maize. However, the...
Tipo: Working or Discussion Paper Palavras-chave: Mexico; Maize; Genetically modified crops; Conservation; Crop Production/Industries.
Ano: 2007 URL: http://purl.umn.edu/42373
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Farmer Willingness to Pay for Seed-Related Information: Rice Varieties in Nigeria and Benin AgEcon
Horna, J. Daniela; Smale, Melinda; von Oppen, Matthias.
A typical private good is defined by its excludability and rivalry characteristics. Information embodied in a technology might not generate rivalry among its users. By contrast, excludability is certainly a characteristic of this kind of information and its delivery can generate incentives for private participation. This study examines farmers’ preferences for seed of new rice varieties and their willingness to pay for seed-related information in villages of Nigeria and Benin. Conjoint analysis is used to estimate the structure of farmers’ preferences for rice seed given a set of alternatives. Farmers are considered to be consumers of seed as a production input, preferring one variety over another based on the utility they obtain from its attributes, which...
Tipo: Working or Discussion Paper Palavras-chave: Seed-related information; Conjoint analysis; Rice attributes; Farmers’ preferences; Technology; Seed markets; Willingness to pay (WTP); Crop Production/Industries.
Ano: 2005 URL: http://purl.umn.edu/58587
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Farmers' Seed Selection Practices and Maize Variety Characteristics in a Traditionally-Based Mexican Community AgEcon
Louette, Dominique; Smale, Melinda.
Experimental results and farmer surveys in a Mexican community indicate that farmers’ seed selection practices protect the phenological integrity of their maize varieties as they define them, despite numerous factors contributing to genetic instability. Analysis of morphological and genetic data suggests that when subjected to significant gene flow through cross-pollination, ear characteristics are maintained through farmers’ selection even though other characteristics may continue to evolve genetically. Because the effects of farmers’ selection practices are confined largely to ear characteristics and plant characteristics that are linked to them, their practices appear to offer only limited scope for improving varieties. Farmers’ expectations of what...
Tipo: Working or Discussion Paper Palavras-chave: Crop Production/Industries.
Ano: 1998 URL: http://purl.umn.edu/7667
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Farmers' Use of Improved Seed Selection Practices in Mexican Maize: Evidence and Issues from the Sierra de Santa Marta AgEcon
Rice, Elizabeth; Smale, Melinda; Blanco, Jose-Luis.
The principal advantage of in situ conservation is that it allows adaptive evolutionary processes to continue in the species that are being conserved. For a cultivated crop species, in situ conservation involves farmers' management of their own genetic resources even as the farmers themselves adapt to a changing environment. Improved seed selection practices and other on-farm breeding strategies have been proposed as a means of providing economic incentives for farmers to continue growing traditional varieties or landraces identified as important for conservation. This paper describes a pilot study among a group of indigenous farmers in the Sierra de Santa Marta, Veracruz, Mexico, who have collaborated in such efforts. The findings raise key issues about...
Tipo: Working or Discussion Paper Palavras-chave: Crop Production/Industries.
Ano: 1997 URL: http://purl.umn.edu/7690
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Gender, Social Capital and Information Exchange in Rural Uganda AgEcon
Katungi, Enid; Smale, Melinda.
Changing agricultural research and extension systems mean that informal mechanisms of information diffusion are often the primary source of information about improved seed and practices for farmers in sub-Saharan Africa. This paper investigates the interactions between gender, social capital and information exchange in rural Uganda. Within the framework of farmer-to-farmer models, we conceptualize the informal information diffusion process to comprise social capital accumulation and information exchange. We assume that each agent participates in information exchange with a fixed (predetermined) level of social capital and examine how endowments of social capital influence information exchange, paying close attention to gender differences. A multinomial...
Tipo: Working or Discussion Paper Palavras-chave: Gender; Social capital; Information exchange; Informal mechanisms; Uganda; Labor and Human Capital.
Ano: 2006 URL: http://purl.umn.edu/50070
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IDENTIFYING APPROPRIATE GERMPLASM FOR PARTICIPATORY BREEDING: AN EXAMPLE FROM THE CENTRAL VALLEYS OF OAXACA, MEXICO AgEcon
Bellon, Mauricio R.; Smale, Melinda; Aguirre, Alfonso; Taba, Suketoshi; Aragon, Flavio; Diaz, Jaime; Castro, Humberto.
Identifying the appropriate germplasm to be improved is a key component of any participatory breeding effort because of its implications for impacts on social welfare and genetic diversity. This paper describes a method developed to select a subset of 17 populations for a participatory breeding project from a set of 152 maize landraces. The larger set of landraces was collected in order to characterize, for conservation purposes, the maize diversity present in the Central Valleys of Oaxaca, Mexico. The method combines data representing the perspectives of both men and women members of farm households and those of genetic resources specialists, including professional plant breeders, gene bank managers, and social scientists. The different perspectives...
Tipo: Working or Discussion Paper Palavras-chave: Mexico; Oaxaca; Maize; Zea mays; Land race; Germplasm conservation; Plant breeding; Selecting; Innovation adoption; Social welfare; Welfare economics; On farm research; Participatory research; Farm Management.
Ano: 2000 URL: http://purl.umn.edu/46524
Registros recuperados: 71
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