Effect of azolla and urea on N, P, K and S content in rice

A field experiment was carried out to investigate the impact of azolla manuring and urea fertilization on N, P, K and S content in BR3 rice. There were six treatments of which four were azolla treatments, one urea application and the other treatment without azolla or urea (control). The azolla treatments were: one, two and thrice incorporations of Azolla and dual culture. Urea was applied at a normal rate (80 kg N/ha). Both azolla and urea applications produced significant effects on N concentration and uptake by rice. Urea supplement gave the best result. Among the azolla treatments, thrice incorporation of azolla showed the highest performance, and it appreas to reduce as much as 60% use of costly urea fertilizer in rice cultivation. Concentration and uptake of other nutrients such as P, K and S were also significantly influenced by azolla and urea applications.