Development and Spread of High-Yielding Rice Varieties in Developing Countries

摘要

The use of high-yielding rice varieties (HYRVs) has expanded sharply in developing countries in recent years. The report reviews the development of these varieties and provides information on the extent of their adoption. Major emphasis is placed on short, fertilizer-responsive varieties, which are generally semidwarfs. They have usually been bred at one of the international agricultural research centers-or are an offspring of a center line or variety and have been further developed in national breeding programs. Adoption data cover the period from the middle 1960s, when the HYRVs were introduced, through the early to mid-1980s.