Diagnosis of Macronutrients in Oil Palm (Elaeis guineensis Jacq.) Using DOP and DRIS Methods

Abstract

Oil palm is an important plant in Indonesia. Good management must be practised to get high production. The fertilization management can still be improved to be more efficient and effective. Efficient fertilizer management begins with correct nutrient diagnosis. Two of the many diagnostic methods are the Deviation from optimum percentage (DOP) method and the Diagnosis and Recommendation Integrated System (DRIS). This research was conducted using secondary data, the results of analysis of nutrient levels and production from several plantations in Kalimantan. The research consisted of various stages, namely data collection, determining productivity, determining norms, nutrient diagnosis, and data processing. The DOP and DRIS methods resulted in norm values of nitrogen, phosphorus, potassium, calcium, and magnesium of 2.63, 0.16, 1.01, 0.77, and 0.29, respectively. Ca has the most negative nutrient index (61% with DOP) and 58% with DRIS. Meanwhile, Mg has the highest positive nutrient index, 55% with DOP and 61% with DRIS, which shows that from all the data. Ca is the nutrient that is most abundant in deficient conditions, while Mg is most abundant in excess conditions. DOP and DRIS showed that the average sequence of nutrient requirements and signs were the same.