Pengelolaan Hara Padi pada Tanah Sawah demi Peningkatan Efisiensi Pupuk

Abstract

The problem in soil fertilizing today is the low fertilizer efficiency. The attempt to raise the fertilizer efficiency is done especially by improving the agronomical techniques, as in the agronomy of paddy rice. Fertilizer management of paddy soils is not the same as of dry land because of the difference in paddy soil characteristics due to water logging that leads to reductive condition. Water logging causes the changes in pH and Eh, the two main factors that affect nutrient solubility in the soil solution. The main nutritional problem in paddy soils is nitrogen deficiency that can be overcome by split application of fertilizer according to rice growth stages, deep placement of fertilizer in the reduced zone, and usage of slow release fertilizer and nitrification inhibitor. Other nutritional problems are the deficiencies of P, K, Zn, S, and Si. The management of N, P, K, Zn, S, and Si fertilizers adjusted with the paddy soil condition and nutrient need of rice plant has to be done to guarantee a high fertilizer efficiency.