Rice productivity and profitability with slow-release urea containing organic-inorganic matrix materials

Abstract Applying slow-release fertilizers is possible means for reducing nitrogen (N) loss in rice production. Matrix-based fertilizers represent novel slow-release fertilizers. To date, there is little consensus about the effect of combined addition of organic and inorganic matrix materials on rice production. We developed a slow-release urea fertilizer with selected organic and inorganic matrix materials. The study aimed to: i) determine the effect of the slow-release urea on rice yield, profit, and agronomic efficiency and ii) elucidate its possible mechanisms. A two-year field experiment was conducted during 2015–2016. Besides, laboratory experiments were conducted to determine the potential N loss risk. Three treatments were set up: control without N application (CK), regular urea treatment (RU, 150 kg N ha–1), and slow-release urea treatment (SU, 150 kg N ha–1). The results showed that rice biomass and grain yield were significantly higher in SU than in RU (P