Effect of Application of Phosphorus, Iron and Manganese under Different Moisture Regimes on the Yield and Nutrition of Rice

A greenhouse experiment was conducted to study the effect of application of P, Fe and Mn on the straw and grain yield of rice, total nutrient uptake and the available P, Fe, and Mn content in soil under three moisture regimes, viz, continuous submerged (W₁), submerged during vegetative stage only followed by moist condition (W₂) and continuously moist (W₃) with the objective to find out if the benefits of continuous soil submergence can be achieved in a moist soil by supplying the above nutrient elements. The results showed that application of P and Mn increased the yield of straw and grain significantly in the moist soil and brought the same to the level comparable with that obtained in the continuously submerged soil under control (Fe₀P₀Mn₀). Application of P and Mn also increased the total uptake of nutrients by the plants and the available P and Mn content in soil under moist condition. The law yield of rice in soil kept continuously under moist condition was attributed to the availability of P and Mn in soil and their lower absorption by the plant. The results suggested that benefits of continuous flooding might be achieved in a moist soil by supplying P and Mn from external sources.