Abstract:In order to improve the water and fertilizer use efficiency of drip fertigation for protected vegetables, the effects of drip fertigation strategies on yield and quality of greenhouse vegetables, and soil nitrogen distribution, nitrogen balance and nitrogen use efficiency in soil-vegetable system were investigated for 15 months in a solar heated greenhouse. The results showed that the fruit yield and the contents of total nitrogen and nitrate were affected significantly by fertigation strategies. The yield, total nitrogen and nitrate content were all higher in the treatment of fertilizing at the early stage of irrigation, and the nitrogen uptake by vegetable increased first and then decreased with the time of fertilization progressing backwards. After harvest, the soil nitrogen contents of the treatment of fertilizing at the end stage of irrigation were the lowest in all soil layers, while the nitrogen consumptions were the highest. In the treatment of fertilizing at the medium stage of irrigation, the apparent loss and surplus of nitrogen in soil-vegetable system were 15.35%~59.13% less than those in other treatments. Nitrogen fertilizer partial productivity and nitrogen apparent efficiency of the treatment of fertilizing at the medium irrigation stage were higher than those in other treatments. The average nitrogen fertilizer apparent utilization rate of the three stubbles in the T2 treatment was 7.09%, 7.41% and 11.48% higher than that in other treatments, respectively. In conclusion, fertigation strategies had a significant comprehensive impact on the yield, quality and nitrogen distribution of soil-vegetable system, and the strategy of applying fertilizer at the medium stage of irrigation schedule was recommend.