ABSTRACT
Rice is one of the most important food crops of the world. Rice production provides employment to the largest sector of the rural population in most of Asia. Rice will grow under appropriate temperature regimes wherever there is enough water to sustain a crop. Rice is grown on a variety of soils ranging from waterlogged and poorly drained to well drained. Submergence creates a unique environment for rice growth and nutrition. Nutrient deficiency symptoms in the rice plant are seen in color of the leaves, stems, and roots, in plant height and tillering habit, and in the development of root systems. The steadily increasing cost of fertilizer has resulted in more emphasis on improved management of fertilizer for efficient use in rice. One method to increase efficiency is to avoid fertilizers where they are not needed and then apply the fertilizers saved to soils where substantial responses are likely.
