Effect of NPK on yield of rice?

Question

Effect of NPK on yield of rice?

Answer 1

NPK are always good for plant growth if they are in limit.

Answer 2

All plants require these macronutrients as well as the 12 micronutrients. Soil test and subsequent examination of ashed plant samples will tell you exactly what is needed per crop type.

Answer 3

All three are needed for rice production.  Rice is an fascinating crop with some interesting interactions.  The mere use of flooding the site alters the soil pH, which in turn affects the availability of nutrients, especially P.  The flooding also reduces oxygen levels in the soil, which leads to conversion of nitrate-N to ammonium-N.

But to answer what I suspect is your real question, the amount of N, P and K a farmer needs to apply will be dependent on the amounts of plant available N, P and K in the soil and if those amounts will remain sufficiently high after flooding.  This will require either advanced knowledge of the site (you have farmed it before) or considerable soil testing and tissue analysis.

Once you have that data, combined with the knowledge of the available fertilizer (including organic materials), the nonlabile to labile conversion rate in the soil, and the crop needs over time, a solid fertilizer program and be determined, applied and the crop production goal attained.