The green revolution research paradigm

Most of the conventional breeding research that launched the green revolution was conducted by the public sector with the explicit goal of creating technologies that could be transferred internationally. International and national public sector researchers bred dwarfing genes into elite wheat and rice cultivars, causing them to produce more grain and shorter stems and enabling them to respond to higher levels of fertilizer and water. These semidwarf cultivars were made freely available to plant breeders from developing countries who further adapted them to meet local production conditions. Private firms were involved in the development and commercialization of locally adapted varieties in some countries, but the improved germplasm was provided by the public sector and disseminated freely as a public good.

The initial focus of the green revolution research was on raising yield potential for the major cereal crops. During the early decades of the green revolution, the crops grown by poor farmers in less favorable agro-ecological zones (such as sorghum, millet, barley, cassava and pulses) were neglected, but since the 1980s modern varieties have been developed for these crops and their yield potential has risen (Evenson and Gollin, 2003). In addition to their work on shifting the yield frontier of cereal crops, public sector plant breeders continue to have successes in other important areas of applied research. These include development of plants with durable resistance to a wide spectrum of insects and diseases, plants that are better able to tolerate a variety of physical stresses, crops that require significantly lower number of days of cultivation, and cereal grain with enhanced taste and nutritional qualities.

3.1.1 The public sector and international technology transfer

Prior to 1960, there was no formal system in place that provided plant breeders access to germplasm available beyond their borders. Since then, the international public sector (the Consultative Group on International Agricultural Research (CGIAR) system) has been the predominant source of supply of improved germplasm developed from conventional breeding approaches, especially for self-pollinating crops such as rice and wheat and for open-pollinated maize. These CGIAR-managed networks evolved in the 1970s and 1980s, when financial resources for public agricultural research were expanding and plant intellectual property laws were weak or nonexistent. The exchange of germplasm is based on a system of informal exchange among plant breeders, which is generally open, and without charge. Breeders can contribute any of their material to the nursery and take pride in its adoption elsewhere in the world, while at the same time they are free to pick material from the trials for their own use.

The international flow of germplasm has had a large impact on the speed and the cost of crop development programs of national agricultural research systems (NARS), thereby generating enormous efficiency gains (Evenson and Gollin, 2003). Evenson and Gollin (2003) report that even in the 1990s, the CGIAR content of modern varieties was high for most food crops; 35% of all varietal releases were based on CGIAR crosses, and an additional 22% had a CGIAR-crossed parent or other ancestor. Thus, while the green revolution promoted the spread of genetically uniform modern varieties in the developing world, the genetic pedigrees of these modern varieties were more complex than the landraces they replaced.

0 0

Post a comment