In order to explore the effects of different reducing fertilizer application modes on wheat yield, nutrient use efficiency in rice-wheat cropping system, and to provide theoretical basis for achieving high efficient application of chemical fertilizer and its zero increase in China, a 3-year field positioning experiment of rice-wheat cropping system was carried out. Six treatments were set including no fertilizer (T1), conventional chemical fertilization (T2), combination of organic manure and chemical fertilizer (T3), reducing 20% chemical fertilizer plus nitrogen synergist (T4), reducing 20% chemical phosphorus fertilizer plus phosphorus activator (T5), and reducing 20% nitrogen and 20% phosphorus plus nitrogen synergist and phosphorus activator (T6). The results showed that compared with T2 treatment, the effects of fertilizer reduction on wheat yield was not significant. The average production investment ratio of three years of T4 treatment was 3.96%, higher than that of T2 treatment, and that of T5 and T6 treatments were 59.21% and 56.24% lower than that of T2 treatment; T4 treatment increased nitrogen absorption efficiency, nitrogen use efficiency and potassium use efficiency by 9.22%-20.70%, 7.01%-28.67%, and 4.69%-7.67%, respectively. T5 treatment could increase the total phosphorus uptake by 15.53%, the range of phosphorus absorption efficiency, partial productivity and use efficiency were increased by 21.43%-46.67%, 12.18%-52.06%, and 3.77%-4.52%, respectively. T6 treatment increased nitrogen absorption efficiency, phosphorus partial productivity, and potassium utilization efficiency by 5.67%-19.40%, 10.88%-43.43%, and 7.38%-12.97%, respectively. T3 treatment had no significant effects on the absorption and utilization of nitrogen and phosphorus, and significantly reduced the partial productivity of potassium. The comprehensive results showed that T6 treatment could stabilize wheat yield and coordinate crop nutrient absorption, but the economic benefit was low due to high cost of phosphorus activator.
Keywords：Wheat yield;Economic benefit;Nutrient use efficiency;Rice-wheat cropping system;Reduced fertilizer application
