Person: Lopez Pereira, M.A.
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Lopez Pereira
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M.A.
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Lopez Pereira, M.A.
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- Impactos del mejoramiento de maíz en América Latina: 1966-1997(CIMMYT, 2000) Morris, M.L.; Lopez Pereira, M.A.Este informe documenta el número y los tipos de variedades e híbridos de maíz lanzados por los programas públicos de mejoramiento entre 1966 y 1997; describe las variedades e híbridos comercializados por organismos públicos y empresas privadas productores de semilla en América Latina en 1997; analiza las tendencias recientes en las ventas de semilla comercial de maíz; estima la superficie sembrada con germoplasma mejorado de maíz en 1996; y examina los factores que han influido en la adopción. Los autores han encontrado que el lugar preponderante que había ocupado la investigación por parte del sector público en el mejoramiento de maíz, corresponde ahora al sector privado, el cual controla la producción de semilla comercial de maíz, y que la industria semillera se ha concentrado cada vez más en América Latina. Si bien la superficie sembrada con germoplasma mejorado de maíz continúa aumentando, su adopción ha sido irregular. Los materiales del CIMMYT se han usado ampliamente en los programas de mejoramiento de los sectores público y privado, y la superficie total sembrada con materiales vinculados con el Centro sigue expandiéndose
Publication - Impacts of maize breeding research in Latin America, 1966-97(CIMMYT, 1999) Morris, M.L.; Lopez Pereira, M.A.This report documents the number and types of maize varieties and hybrids released by public breeding programs between 1966 and 1997, describes the varieties and hybrids marketed by public seed agencies and private companies in Latin America in 1997, analyzes recent trends in commercial maize seed sales, estimates the area planted to improved maize germplasm in 1966, and discusses factors that have influenced adoption. The authors find that the primary locus of maize breeding research has shifted to the private sector, the private sector now dominates commercial maize seed production, and the maize seed industry in Latin America has become increasingly concentrated. Although the area planted to improved maize germplasm continues to increase, adoption has been uneven. The use of CIMMYT materials has been extensive in public has well as private sector breeding programs, and total area shown to CIMMYT-related materials continues to increase.
Publication - Maize production and agricultural policies in Central America and Mexico(CIMMYT, 1999) Sain, G.; Lopez Pereira, M.A.This paper reviews trends in maize production and consumption in Central America and Mexico in the context of the political and economic changes taking place in the region since the 1970's. The authors focus on the effects of the structural adjustment programs in the 1980's and 1990's. The analysis begins by reviewing the economic context in which maize production occurs in the region and the main economic policy instruments affecting the maize economy. Next, trends in maize consumption and production are analyzed, along with the main factors influencing maize production, including trends in the public financing of maize research and extension. The authors find that several factors related to structural adjustment have defined -- and are still defining -- the course of agriculture, including maize production, in the countries of the region. The impact of these factors on maize production, consumption, and import trends has been different in Central America and in Mexico. In particular, the reduction or complete elimination of production incentives, the reduction of trade barriers, the liberalization of input and product prices, the deregulation of the currency exchange rate, the control of inflation, and the restructuring of agricultural research systems between the public and the private sectors have determined how basic grains are produced in the region and how they will be produced in the future. Furthermore, the visible and increasing deterioration of the natural resource base has raised great concern about the need to promote more sustainable, environmentally friendly uses of production systems and natural resources.
Publication - Las industrias de la semilla de maíz en Brasil y México: desempeño anterior, problemas actuales y perspectivas para el futuro(CIMMYT, 1997) Lopez Pereira, M.A.; Garcia, J.C.Este documento describe los resultados de un estudio de los principales factores que afectan el desarrollo de la industria de semilla de maiz en Brasil y Mexico (y, por extension, de otros paises en desarrollo). Los autores establecen un marco que pueden usar los investigadores y quienes formulan las politicas para evaluar el desempeno de la industria de la semilla en los paises en desarrollo. Se emplea este marco para analizar las industrias de semilla de Brasil y Mexico, donde circunstancias muy diferentes influyen sobre el desarrollo, la eficiencia y la estructura de la industria de la semilla. E1 analisis presta especial atencion a las distintas estrategias de mejoramiento de maiz aplicadas por los sectores publico y privado, las medidas de la competitividad y la eficiencia de la industria y las ventajas y desventajas que implica desarrollar y producir distintos tipos de semilla de maiz, en particular las variedades mejoradas de polinizacion libre en comparacion con diversos tipos de hibridos . Los autores identifican problemas de la industria de la semilla esenciales para los investigadores, los administradores de los programas nacionales y quienes formulan las politicas agricolas en los paises en desarrollo, especialmente los problemas vinculados con las funciones apropiadas de los organismos publicos y privados en la industria de la semilla de maiz del mundo en desarrollo.
Publication - The maize seed industries of Brazil and Mexico: past performance, current issues and future prospects(CIMMYT, 1997) Lopez Pereira, M.A.; Garcia, J.C.This paper describes results of a study of the main factors affecting the development of the maize seed industries in Brazil and Mexico (and, by extension, other developing countries). The authors develop a framework that researchers and policy makers can use to evaluate seed industry performance in developing countries. This framework is used to analyze the seed industries of Brazil and Mexico, where very different sets of circumstances influence seed industry development, efficiency, and structure. The analysis gives special attention to the different maize breeding strategies pursued by the public and private sectors, measures of industry competitiveness and efficiency, and the trade-offs involved in developing and producing different kinds of maize seed, particularly improved open-pollinated maize varieties versus different types of hybrids. The authors identify key seed industry issues for researchers, administrators of national maize programs, and agricultural policy makers in developing countries, especially issues related to the appropriate roles for public and private organizations in maize seed industries in the developing world.
Publication - Impacts of international maize breeding research in the developing world, 1966-1990(CIMMYT, 1994) Lopez Pereira, M.A.; Morris, M.L.The impacts of maize breeding research for non-temperate environments in the developing world by national agricultural research systems (NARSs) and the International Maize and Wheat Improvement Center (CIMMYT) over 1966-90 are analyzed. Collaborative maize breeding by NARSs and CIMMYT resulted in the development and release of 842 maize varieties and hybrids by public research organizations in developing countries during 1966-90. Of these materials, 53% contained CIMMYT germplasm. Although the share of hybrid releases rose substantially follOWing increased emphasis on hybrids by NARSs, for the period as a whole hybrids comprise just 35% of releases. Maize releases are distributed fairly evenly between tropical lowlands (53%) and tropical midaltitudes, tropical highlands, and the subtropics (47%). In non-temperate ecologies an estimated 24.6 million hectares were planted to improved maize in 1990 (43% of the 57.7 million hectares under maize in the countries under study). Public sector materials accounted for 19.9 million hectares (81%) of the area under improved maize; 4.7 million hectares (19%) were under proprietary materials. Improved maize containing CIMMYT germplasm was planted on 13.5 million hectares in 1990 (55% of the area under improved materials), mostly open-pollinated varieties in tropical lowlands. The fact that more than half (33 million hectares) of the developing world's maize area is still planted to unimproved varieties suggests that significant barriers continue to slow adoption of improved maize germplasm. To reach farmers who do not plant improved maize, breeders must continue developing varieties and hybrids adapted to marginal growing conditions, especially materials tolerant to biotic and abiotic stresses and low levels of external inputs. The still modest use of improved maize germplasm in some regions of the developing world also reflects farmers' difficulty in obtaining seed and points to the need for more effective maize seed industries, especially better seed production and distribution. Finally, to obtain more accurate estimates of the economic impacts of maize breeding research, researchers must monitor 1) the flow of germplasm from public research organizations, especially the use of this germplasm by private sector organizations; 2) farmers' adoption of improved maize; and 3) the yield effects of using improved maize at the farm level.
Publication - Emerging roles of the public and private sectors of maize seed industries in the developing world(CIMMYT, 1995) Lopez Pereira, M.A.; Filippello, M.P.Interactions between public and private sector organizations in the world maize seed industry are analyzed, with emphasis on the developing world. Information is presented on the share of total maize seed sales in 1992 by different kinds of seed enterprise and by different types of seed (hybrids, open pollinated varieties) and its origin (public or private sector breeding programs). In most developing countries, private organizations remain the major producers and distributors of maize seed; maize seed production and distribution by the public sector has tended to diminish. Public breeding systems, however, are still important in maize seed industries; more than half of the seed sold in developing countries in 1992 was of public origin. Although schemes for direct production and distribution of maize seed by the public sector are largely a thing of the past, public breeding systems will remain important for fostering the development of domestic private seed enterprises and small-scale seed producers, and conducting research directed at small-scale farmers.
Publication - Technical change in maize production: a global perspective(CIMMYT, 1994) Byerlee, D.; Lopez Pereira, M.A.The stages of technological change in maize production in commercial and small-scale semisubsistence systems are discussed and variation in the use of improved varieties/hybrids and adoption of associated inputs are noted. The impacts of the new biotechnologies and the increasing emphasis on resource-conserving technologies are also discussed with respect to prospects for technological progress in maize production in developing countries. Finally, strategic decisions that must be made by national agricultural research systems in developing countries are reviewed, especially decisions related to the relative emphasis to give to development of improved open-pollinated or hybrid maize varieties; the participation of the public and private sectors in research to achieve technological progress in maize production; and the types of farmers on which the public research system should focus its efforts.
Publication - La producción de maíz de temporal en México: tendencias, restricciones y retos tecnológicos e institucionales para los investigadores(CIMMYT, 1992) Saad, L.; Hibon, A.; Triomphe, B.; Lopez Pereira, M.A.Este documento examina las tendencias de la producción de maíz de temporal en México en los últimos decenios y la experiencia del INIFAP / OMMYT/ ORAD en la investigación en fincas (IEF) en las tierras bajas tropicales de México, para evaluar las perspectivas de una mayor producción de maíz en las regiones de temporal. Los datos de la producción nacional muestran que la superficie de maíz de temporal ha permanecido estable desde 1960 e, incluso, ha disminuido en el último decenio. Los rendimientos medios se han nivelado desde 1980 después de fuertes aumentos en los 70. No obstante, la tasa de incremento de los rendimientos medios necesaria para satisfacer la demanda prevista para el año 2000 (1.7% anual) superan con mucho las tasas de aumento de los rendimientos registradas desde 1980. Además, es probable que los precios de los insumos y créditos usados en la producción de maíz sean menos favorables en el futuro de lo que fueron antes, lo que implica que es factible que la superficie sembrada con maíz y los rendimientos del cereal disminuyan a menos que se disponga de nuevas tecnologías. Los resultados de seis años de IEF en las tierras bajas tropicales de México indican que es posible generar tecnologías económicamente viables, que permitirán a los agricultores aumentar los rendimientos del maíz de temporal. Sin embargo, hacer esto en gran escala implica la reorganización del programa de investigaciones, un mayor énfasis en la investigación con la participación de los agricultores y una mayor inversión en investigaciones agrícolas.
Publication - The economics of quality protein maize as an animal feed: case studies of Brazil and El Salvador(CIMMYT, 1992) Lopez Pereira, M.A.This study examines the potential of quality protein maize (QPM) as an animal feed ingredient in Brazil and EI Salvador. The minimum ingredient cost of pig and chicken feed with and without QPM and the optimal level of the main ingredients in the rations are obtained using linear programming models and compared for both cases. Sensitivity analysis is performed on relative prices of soybean meal (the main protein source), regular maize and sorghum (the main energy sources), synthetic lysine (the main amino acid supplement), and QPM. Model results indicate that QPM has the potential to reduce the production cost of pig feed by as much as 5.0% in Brazil and 3.4% in EI Salvador. Chicken feed cost savings of QPM are as high as 2.9% in Brazil and 2.8% in EI Salvador. If assigned the same price as regular maize, QPM constitutes 80% of the optimal pig feed in Brazil, replacing all regular maize and synthetic lysine and 40% of the soybean meal. At a 5% price premium over regular maize, QPM constitutes 50% of the optimal pig diet. In EI Salvador, QPM priced the same as regular maize also forms 80% of the pig diet; at a 5% price premium, QPM constitutes 40% of the diet. In both countries savings at the industry level depend on the size and technological sophistication of the pig industry and on the prices of the feed ingredients with which QPM competes. Future research and agricultural policy should emphasize means of distinguishing QPM from regular maize, improvement of QPM's storability, and promotion of QPM varieties already available.
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