May 1999 - The agriculture sector must nearly double biological yields on existing farmland to meet food needs, which will double in the next quarter century. A sustainable approach to providing agricultural extension services in developing countries-minimal external inputs, a systems...

"The paper reviews the literature on the characteristics and impact of opinion leaders on the diffusion of new knowledge, concluding that there is no clear evidence on whether opinion leaders are more effective if they are similar in socioeconomic attributes to the other farmers rather than...