ECONOMIC GROWTH CENTER

                      YALE UNIVERSITY

                      P.O. Box 208269
                     27 Hillhouse Avenue
                   New Haven, CT 06520-8269


               CENTER DISCUSSION PAPER NO. 771



               RICE VARIETAL IMPROVEMENT AND
          INTERNATIONAL EXCHANGE OF RICE GERMPLASM


                      Robert E. Evenson
                       Yale University




                        February 1997








Note:  Center Discussion Papers are preliminary materials circulated to
       stimulate discussions and critical comments.

                       Abstract



    Rice is the most important food grain in developing countries.  Rapid
population growth in developing countries during the 1950s and 1960s presented
a massive challenge to rice producers.  Rice production would have to be
expanded at historically unprecedented rates to maintain per capita rice
consumption levels.  That challenge was met.  Rice production expanded more
rapidly than population.  The challenge was met primarily by increased yields
per hectare of land.  This paper documents the role of varietal improvement
and of genetic resources in achieving yield improvement.  It shows that
varietal improvement was international in character with the International
Rice Research Institute in the Philippines playing the leading role.  More
than 100 national rice breeding programs contributed to the pool of
approximately 2,000 rice varieties constituting the "green revolution" in
rice.  Accss to and the international exchange of genetic resources in the
form of farmer selected "landraces" was vital.  More than ninety percent of
the green revolution rice varieties were developed from genetic resorces
originating in more than one country.








KEY WORDS: Rice Production, Genetic Resource Evaluation, Rice Productivity