Fuente: WIPO "tomato" New type urea-based granular fertilizers provided with a multiple-layer coating. The coating comprises, independently distributed among the layers: an ammonium converting microorganism, an ureolytic microorganism, an oil-binder mixture and an anticaking agent. The present granules are meant for administration to the soil for purpose of fertilization. They may be administered a such or as part of a composition comprising them. The granules of the invention provide a prolonged fertilizing effect combined with an enhanced conversion of urea in plant-absorbable nitrogen, mainly in form of nitrites and nitrates, advantageously accompanied by a reduced loss on nitrogen in form of gaseous ammonia and a prolonged duration of action.