ABSTRACT
Sustainable increase in rice production in the near future requires substantial improvement in productivity and effi ciency. Rice yield and production have been considerably increased during the last 30 years. In a number of countries, yields of rice in favourable ecologies have reached the research yield potential of the present generation of high yield ceiling, where yield gaps are nearly closed. These increases not only enhance rice productivity but also the effi ciency in production systems, resulting in high economic output as well as high income of farmers.
