E-Book Overview
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.
E-Book Content
NITROGEN ECONOMY OF FLOODED RICE SOILS
Developments in Plant and Soil Sciences 1.
J. Monteith and C. Webb, eds., Soil Water and Nitrogen in Mediterranean-type Environments. 1981. ISBN 90-247-2406-6 2. J.C. Brogan, ed., Nitrogen Losses and Surface Run-off from Landspreading of Manures. 1981. ISBN 90-247-2471-6 3. J.D. Bewley, ed., Nitrogen and Carbon Metabolism. 1981. ISBN 90-247-2472-4 4. R. Brouwer, I. Gasparikovii, J. Kolek and B.C. Loughman, eds., Structure and Function of Plant Roots. 1981. ISBN 90-247-2510-0 5. Y.R. Dommergues and H.G. Diem, eds., Microbiology of Tropical Soils and Plant Productivity. 1982. ISBN 90-247-2624-7 6. G.P. Robertson, R. Herrera and T. Rosswall, eds., Nitrogen Cycling in Ecosystems of Latin America and the Caribbean. 1982. ISBN 90-247-2719-7 7. D. Atkinson et aI., eds., ' Tree Root Systems and their Mycorrhizas. 1983. ISBN 90-247-2821-5 8. M.R. Saric and B.C. Loughman, eds., Genetic Aspects of Plant Nutrition. 1983. ISBN 90-247-2822-3 9. J.R. Freney and J.R. Simpson, eds., Gaseous Loss of Nitrogen from Plant-Soil Systems. 1983. ISBN 90-247-2820-7 10.. United Nations Economic Commission for Europe. Efficient Use of Fertilizers in Agriculture. 1983. ISBN 90-247-2866-5 11. J. Tinsley and J.F. Darbyshire, eds., Biological Processes and Soil Fertility. 1984. ISBN 90-247-2902-5 12. A.D.L. Akkermans, D. Baker, K. Huss-Danell and J.D. Tjepkema, eds., Frankia Symbioses. 1984. ISBN 90-247-2967-X 13. W.S. Silver and E.C. Schroder, eds., Practical Application of Azolla for Rice Production. 1984. ISBN 90-247-3068-6 14. P.G.L. Vlek, ed., Micronutrients in Tropical Food Crop Production. 1985. ISBN 90-247-3085-6 15. T.P. Hignett, ed., Fertilizer Manual. 1985. ISBN 90-247-3122-4 16. D. Vaughan and R.E. Malcolm. eds .. Soil Organic Matter and Biological Activity. 1985. ISBN 90-247-3154-2 17. D. Pasternak and A. San Pietro, eds., Biosalinity in Action: Bioproduction with Saline Water. 1985. ISBN 90-247-3159-3. 18. M. Lalonde, C. Camire and J.O. Dawson, eds., Frankia and Actinorhizal Plants. 1985. ISBN 90-247-3214-X 19. H. Lambers, J.J. Neeteson and I. Stulen, eds., Fundamental, Ecological and Agricultural Aspects of Nitrogen Metabolism in Higher Plants. 1986. ISBN 90-247-3258-1 20. M.B. Jackson, ed. New Root Formation in Plants and Cuttings. 1986. ISBN