Evaluation of the effect of coated urea on rape growth

A pot experiment was set up to study the effects of four different coated urea fertilizers on rape growth through appraising their impact on soil urease activity,yield and quality of rape and fertilizer utilization rate.Based on the above mentioned indices,the best treatment (FSU-4) was selected that fully met rape nutrition demand just from single application.Compared with urea treatment,rape biomass raises by 70.8%,Vc content increases by 7.8%,and chlorophyll content increases by 46.1% when treated with FSU-4;while nitrate content drops by 46.0%.In two experiments conducted,fertilizer utilization rate of FSU-4 increases by 36% compared with urea.Suppression of urease activity by coated urea is observed in the early rape growth stage,but subsequently gains vigor in the late stage;an unexplained phenomenon that needs further research.