Properties of a new slow-release nitrogen fertilizer “SUPER-IB”

Abstract

Isobutylidene diurea (IBDU) is well--known as a hydrolytic, slow--release nitrogen fertilizer. The powder of IBDU was granulated by agitation granulator with urea--formaldehyde condensation as a binder, in order to improve the physical characteristic and the fertilizer use efficiency. We termed the granulated product ``SUPER--IB''. Three experiments were carried out to evaluate the characteristic of SUPER--IB as a slow--release fertilizer. The breaking hardness (kg/granule) of SUPER--IB was over 1.8, and the hygroscopicity was very low. The mineralization rate of SUPER--IB was increased by higher temperatures. In the paddy rice test, almost equal yields was obtained by only basal fertilization of SUPER--IB in comparison with conventional application of compound fertilizer. It is concluded that SUPER--IB has a ideal physical characteristic and a superior fertilizer use efficiency compared to conventional treatments.