Derek Byerlee

Farmers' Stepwise Adoption of Technological Packages: Evidence from the Mexican Altiplano

Agricultural research and extension programs in developing countries, rather than following the conventional package approach, should be designed to take into account the fact that farmers adopt improved technological components in a stepwise manner. On-farm experimental and survey data collected from two rainfall zones in a high valley of Mexico are synthesized to show that farmers have rationally followed a stepwise process of adopting improved varieties, fertilizer, and herbicide for barley, reflecting the relative profitability and riskiness of each component in each zone. Despite significant interactions between the components, it was still possible for farmers to adopt individual components in a sequential manner.

Has the green revolution been sustained? The quantitative impact of the seed-fertilizer revolution in Pakistan revisited

Abstract Quantitative impacts of the Green Revolution on food production in the Punjab of Pakistan are reviewed and the effects of different technologies on wheat yields over the past two decades decomposed. New quantitative evidence of sustainability problems in irrigated systems is presented. The yield increases expected in the post-Green Revolution period from the further spread of modern wheat varieties, a tripling of fertilizer dosage, and the release of newer higher yielding varieties have been cancelled by problems resulting from increased cropping intensity, use of poor quality groundwater, low fertilizer efficiency, and increased weed and disease losses. New directions in institutional policies and research and extension strategies are outlined to improve efficiency and sustainability in wheat production and prevent Pakistan from becoming a major food grain importer in the coming decades.

A Joint-Product Analysis of the Adoption of Modern Cereal Varieties in Developing Countries

Semi-dwarf wheat varieties have been slow to diffuse in some regions despite their superior grain yield. We analyze varietal differences in yields of the joint products of grain and straw, the decision to adopt new varieties, and nitrogen demand. The low straw yield of semi-dwarf varieties under low input conditions is shown to be a plausible explanation for their slow adoption in some regions. First generation modern varieties induced a large increase in the derived demand for nitrogen, but subsequent varietal development appears to have had little impact on nitrogen demand.

Research for marginal environments: Are we underinvested?

Abstract Evidence is presented to show that adoption of modern wheat varieties in rainfed marginal environments of the developing world has lagged substantially compared to adoption in favoured well-watered areas. Possible reasons for this lag are discussed, and a simple congruency model is used to examine the case for shifting research resources from favoured to marginal environments, with particular reference to wheat breeding. Application of the model to resource allocation in wheat research at the international level and for India, a major wheat-producing country, suggests that the proportion of research resources invested in marginal environments has been adequate or even a bit high relative to the share of the value of wheat produced in these environments, taking into account both efficiency and equity criteria.

Calculating levels of protection: Is it always appropriate to use world reference prices based on current trading status?

Abstract Protection measures such as the nominal protection coefficient (NPC), the effective protection coefficient (EPC), the producer subsidy equivalent (PSE), and the consumer subsidy equivalent (CSE) are conventionally calculated using world reference prices based on current trading status. Under certain conditions, the conventional approach can lead to incorrect estimation of the degree and sometimes even the direction of protection. This paper spells out the conditions under which use of world reference prices based on current trading status is incorrect and presents data for wheat in Pakistan to illustrate how failure to consider these conditions can lead to misleading policy recommendations.

Economic Returns to Crop Management Research in a Post-Green Revolution Setting

Returns to research studies have neglected research on crop management (CMR), which may account for half of all crop research. Because CMR enhances the efficiency of input use, returns to CMR are hypothesized to increase in settings characterized by high input levels and high yields. A method is developed to estimate returns to CMR, and this method is applied to wheat research in a post-green revolution setting in northwest Mexico. The results suggest that returns to CMR are positive over a range of model assumptions.

Food Pricing Policy in Developing Countries: Bias against Agriculture or for Urban Consumers?

Price policy discrimination against agricultural producers, in order to provide cheap food for urban consumers, has been widely cited in development forums as a cause of agricultural stagnation. Evidence is presented that suggests no consistent pattern of discrimination against producers for a major food commodity, wheat. However, consumer subsidies and trade policies have reduced bread prices to urban consumers in many countries. Price data from the early 1980s are assembled for thirty-one developing countries. Nominal protection coefficients for producers and consumers at official and corrected exchange rates and wheat-fertilizer price ratios are estimated for each country.

Reconciling conflicts in sequential cropping patterns through plant breeding: The example of cotton and wheat in Pakistan's Punjab

Abstract A cropping systems framework is used to analyze breeding priorities between wheat, a staple food crop, and cotton, a cash crop, which are increasingly grown in a sequential double cropping pattern in Pakistans Punjab. Survey and experimental data are presented to show how conflicts in harvesting of cotton and planting of wheat are being resolved through earlier cotton varieties and wheat varieties that perform well over a range of planting dates. However, changes in cotton pest management and price relationships between cotton and wheat call for continuous review of breeding priorities.

Agricultural research strategies for favoured and marginal areas: The experience of farming systems research in Pakistan

This paper draws on the results of farming systems research (FSR) conducted over five years at eight sites distributed throughout Pakistan. The main research findings with respect to the irrigated plains, or favoured areas (four sites), and the marginal mountainous and rainfed areas (four sites) are summarized, with emphasis on the role of system interactions in technology development. In favoured areas, most system interactions occur between crops grown in multiple cropping patterns, whereas in marginal areas, crop-livestock interactions dominate. Appropriate research strategies for each kind of environment are discussed. It is concluded that although there is a need for quite different research strategies for favoured and marginal areas, the methods and perspective of FSR are equally appropriate and even critical for achieving future gains in agricultural productivity in each type of environment. Estrategias de investigacion agricola en zonas favorecidas y marginales: Experiencias recogidas durante la investigacion de sistemas agricolas en Pakistan

Strengthening Linkages in Agricultural Research through a Farming Systems Perspective: The Role of Social Scientists

SUMMARY The principal contribution that the farming systems perspective brings to agricultural research is a farmer and problem-solving orientation. Development of this orientation helps strengthen linkages in national research systems between commodity programmes and between disciplines for both applied and adaptive research. It can also strengthen linkages between research and extension and between research and policy analysis. Issues in strengthening each of these linkages are briefly reviewed with particular emphasis on the socio-economic dimensions and the potential role of social scientists. It is argued that the farming systems perspective in agricultural research should be seen as performing an integrative role in research systems. This can often be developed without significant institutional reorganization. Derek Byerlee y Robert Tripp: Reforzando vinculos en la investigation agricola a traves de una perspectiva de sistemas agricolas: Lafuncionde los cientificos sociales. RESUMEN El principal aporte que trae la perspectiva de los sistemas agricolas a la investigacion agricola es una oricntacion hacia el cultivador y la resolucion de problemas. El desarrollo de esta orientation ayuda a reforzar los vinculos dentro de los sistemas nacionales de investigacion entre los programas de productos y entre disciplinas para la investigacion tanto aplicada como adaptiva. Tambien puede reforzar vinculos entre la investigacion y la extension y entre la investigacion y el analisis de politicas. Se repasan brevemente los temas en el refuerzo de cada uno de estos vinculos, con enfasis especial en las dimensiones socioeconomicas y la posible funcion de los cientificos sociales. Se argumenta que la perspectiva de los sistemas agricolas en la investigacion agricola deben verse como cumpliendo un papel de integration en los sistemas de investigacion. Esto a menudo puede ser desarrollado sin una gran reorganization institucional.