The steadily increasing cost of nitrogen fertilizer has resulted in more
emphasis on basic and applied studies to improve nitrogen use efficiency
in lowland rice. The efficiency of fertilizer nitrogen in farmers'
fields is shockingly low a luxury resource-scarce farmers in tropical
Asia can ill afford. We believe it is critical to quantify the basic
transformation processes and develop management practices for higher N
use efficiency for two reasons. They are: 1. Nitrogen fertilizer
together with water management is a key factor for achieving the yield
potentials of modern rices. 2. Fertilizer nitrogen prices are high and
most Asian rice farmers are poor. The International Rice Research
Institute (IRRI), Philippines; Internation- al Fertilizer Development
Center (IFDC), USA; Commonwealth Scientific and Industrial Research
Organization (CSIRO), Australia; U.S. Universities (Louisiana, Cornell,
California, Arkansas and others); and Dr Justus Leibig University in
West Germany are actively engaged in individual or collaborative
research that addresses basic transformation processes on N gains and
losses and management practices to maximize N use efficiency in rice. It
is appropriate to update and summarize, in a double issue of Fertilizer
Research, the 10 papers presented at the special symposium organized by
the American Society of Agronomy (ASA) at the 75th Annual Meeting in
Washington, D.C. in 1983. S.K. De Datta, Head of Agronomy Department,
IRRI, was chairman of the International Agronomy Division of ASA (A-6)
in 1982 and 1983.