Abstract:

Based on the scientific and reasonable fertilization scheme, according to supply capacity of soil nutrient, fertilizer requirement regularity of rice, and target yield, this experiment adopted the principles of soil to yield determination, yield to fertilization requirement and application of slow-release fertilizer to explore the influence of polyurethane coated slow-release fertilizer on the yield and fertilizer use efficiency of double-cropping rice in Wucheng Distrist, depending on the formulation technology of soil testing. The results showed that for the early rice, the target yield and actual yield were 6 000.0 kg·hm^-2, and 6 405.0 kg·hm^-2, respectively, under full fertilizer treatment. The N, P and K use efficiencies were 44.9%, 25.2% and 49.1%, respectively. For the late rice, the target yield and actual yield were 8 250.0 kg·hm^-2, and 8 707.5 kg·hm², respectively, under full fertilizer treatment. The N, P, K use efficiencies were 43.6%, 27.8% and 51.6%, respectively. Polyurethane coated slow-release fertilizer is an excellent slow-release fertilizer. The average N, P and K use efficiencies were 44.3%, 26.5% and 50.4%, respectively, by applying polyurethane coated slow-release fertilizer. Thus, it is recommended to use polyurethane coated slow-release fertilizer instead of general compound fertilizer.

Key words: double-cropping rice, slow-release fertilizer, utilization efficiencies of nutrients