NUTRIENT DEMANDS OF Tenera OIL PALM PLANTED ON INLAND SOILS OF MALAYSIA

Oil palm is unrivalled in its ability to convert solar energy into dry matter and vegetable (palm) oil. This process requires a large amount of nutrients, which must be supplied through soil or fertilizers. Good nutrient management, which includes a site-specific nutrient management plan, is important to achieve high yields of palm oil. Good knowledge of nutrient requirements at the various stages of growth and development of the oil palm is needed for the nutrient management plan and greater fertilizer-use efficiency. This paper highlights the nutrient requirements of oil palm based on the nutrient contents of tenera palms from analysis of their nutrients in fresh fruit bunches (FFB), trunk and roots in a 3 2 NK x 2P factorial fertilizer trial on Bungor series soil. The results showed that more of N is actually removed than previously estimated but an annual application of 4.2 kg ammonium sulphate per palm meets the nutrient demands to produce 30 t FFB ha -1 , i.e., the N applied balances the N demand. However, the K applied was surplus (23% of the 3.5 kg potassium chloride per palm applied) to the actual requirement of the palms. The unaccounted P (surplus of 20%) could have been fixed by the soil, which suggests that more phosphate rock fertilizer, i.e. over 2 kg palm -1 yr -1 , is required to compensate for the P immobilized by the soil. The paper also proposes a comprehensive and sound