Efficacy Of Control Release Fertilizer On Nutrient Uptake And Fresh Fruit Bunch Production In North Sumatra- Indonesia.

Abstract

Controlled Release Fertilizer/CRF was an alternative solution to increase the fertilizer efficiency by reducing rate of application, depressing fertilizer round application and losses through leaching and volatilization.  The trial aimed to compare CRF with three different dosage with conventional (straight)  fertilizer and to distinguish it’s effect to vegetative growth, nutrient uptake and yield of  the oil palm. Randomized block design was used with eight treatments and three replications. The result showed that there was no significant difference statistically at P 0,05 between CRF and straight fertilizer in term of vegetative growth, nutrient uptake and yield of oil palm, however there were an indication that the CRF at rate of 4 kg/palm//year tend to increase frond weight and leaf area  by 3%, improved the nutrient uptake especially on Potasium in the leaf  by 9% and consequently improved the bunch weight and number of bunch per palm by 7%  and 3% respectively and eventually increased the fresh fruit bunch per ha by 7%  compared to straight fertilizer with average dosage of 5,2 kg/palm/year over periode three years of maturity phase. The lower dosage of CRF require the enhancement after the sixth month of CRF application.  To sum up CRF could substitute the straight fertilizer on the newly mature phase and  CRF at 4kg/palm/year increased fresh fruit bunch production up to 7% compared to straight  fertilizer and consequently depressed the man power requirement and minimized the negative impact of fertilizer to the environmental.