Fertilizer management in deepwater rice
1988
Puckridge, D.W. | Thongbai, P. (International Rice Research Inst., Bangkok (Thailand))
This paper summarizes the results of many fertilizer experiments and analyzes the conditions under which fertilizer responses are likely. In areas where a P response is obtained, a basal P application each year or a periodic application of rock phosphate can be decided on economic grounds. Decisions on use of N fertilizer are more complex, and must take into account the soil type, sources of N other than fertilizer, weather pattern in the preflood period, length of this period, rate of rise of floodwater, and characteristics of the rice variety. The dry weight and N content of plant samples from unfertilized fields can give an integrated value for supply of N from the environment and provide a basis for calculating N requirements.
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