Deep placement of nitrogenous fertilizer (N) is an alternative for increasing the N use e$ciency of wetland rice
besides minimizing the adverse e!ects of fertilizers on the environment. It has been found to limit the loss of
N due to surface runo!, leaching, volatilization and denitri"cation that lead to reduction in applied N. Di!erent
machines as well as N materials (granular, urea supergranules or briquettes, liquid N) have been introduced for
this method. Although deep placement of fertilizer increased N use e$ciency in rice-growing countries, the
machines meant for this purpose have not been well accepted due to problems in performance consistency and
commercial unavailability or extra cost of recommended materials. Despite these problems, however, several
prototypes have shown potential but their acceptance maybe limited unless these promising mechanisms are
adapted into a system that addresses the "eld and socio-economic conditions of Asian farmers. A fertilizer
management system that combines machine deep placement, crop establishment and farmers' timing of
application using the commercially available materials could enhance adoption of the technology. Further
re"nements of the promising devices as well as addressing farmers' constraints are, thus, recommended for
a better acceptance of deep placement in the rice-growing countries of Asia