Engineering, Crop Science 

The FAO Expert Consultation on Yield Gap and Productivity Decline in Rice Production, held in Rome from 5 to 7 September 2000, recognized the existence of a sizeable yield gap between research and average farm yields across ecologies, regions within ecologies and crop seasons in all rice-growing countries worldwide. The key constraints contributing to the yield gap range from biophysical to socio-economic issues. The actual yield potential of a variety is thus the result of overcoming all these constraints. Narrowing of the yield gap requires precise assessment of problems present in rice production, indentification of key technology packages for a specific location and determination of appropriate remedies. This manual provides guidelines for the identification of biophysical constraints and suggests measures that could be taken to circumvent the shortcomings and boost yields on farmers' fields. - from Amzon