Phosphorus Dynamics and Rice Yield Response to Different Fertilization in Acid Soils

Abstract

Proper fertilizer management is needed to overcome the problem of phosphorus deficiency in acid soils which is a major constraint in rice production. Knowledge on phosphorus (P) fractions is vital in understanding the P bioavailability. The objective of this study was to compare the effect of organic manures and compost, cattle manure, poultry manure and sheep manure and Triple Super Phosphate (TSP), on phosphorus availability and rice yield. The treatment with TSP + recommended chemical fertilizer (200 kg ha-1 NPK 15:15:15, 50 kg ha-1 Urea (tillering stage) + 50 kg ha-1 MOP (panicle initiation)) recorded highest yield but showed no significant difference with TSP+ cattle manure treatment. The lowest yield, available P, total P and highest Al-P and Ca-P recorded in control (no fertilizer). This indicates that application of P is necessary to maintain the soil phosphorus level at optimum to achieve targeted yield in acid soil. Maximum level of available and total phosphorus was recorded by application of TSP +cattle manure. Cattle manure with TSP increased yield and P availability which helps to reduce the mineral fertilizer usage and production cost. This could be a good practical technique that improves soil P content and increases the yield in acid soils.