1Weifang Institute of Science and Technology，Shouguang 262700，Shandong，China；2Shouguang Vegetable Industry Group Co.，Ltd. of Shandong，Shouguang 262700，Shandong，China；3Shouguang Vegetable Industry Development Center，Shouguang 262700，Shandong，China；4Shandong Vegetable Engineering and Technology Research Center Co.，Ltd.，Weifang 262700，Shandong，China；5Facility Vegetable Technology Innovation Center of Shandong，Shouguang 262700，Shandong，China；6Weifang Seed Valley Technology Co.，Ltd.，Weifang 261111，Shandong，China
Abstract：In order to reduce the usage amount of chemical fertilizers and improve nitrogen use efficiency，this paper studied the effects of fertilizer synergist polyaspartic acid and ETS biological compound fertilizer on facility tomato quality，yield and nitrogen use efficiency under the condition of reduced application of chemical fertilizers．This experiment set early spring-cultivation，autumn and winter cultivation，and 5 treatments，including no fertilizer applied（CK0）；conventional chemical fertilizer（CK）；chemical fertilizer +polyaspartic acid（T1），N was 80% of the CK；ETS biological compound fertilizer（T2）；ETS bioorganic fertilizer + polyaspartic acid（T3），N was 80% of the T2．The results showed that the application of polyaspartic acid and ETS biological compound fertilizer could significantly increase tomato yield，improve nutritional quality，increase dry mass quantity of each plant part，and enhance tomato ability to absorb nitrogen．The early spring-cultivation，autumn and winter cultivation showed similar change trends．Compared with the CK，in early spring-cultivation of T3 the average yield increased by 16.47%，sugar-acid ratio increased by 38.12%，nitrogen fertilizer absorbtion and utilization rate increased by 13.77 percentage point．Compared with the CK，in T2 tomato yield increased by 18.83%，nitrogen fertilizer absorbtion and utilization rate increased by 8.11 percentage point．In conclusion，using ETS bio-compound fertilizer to replace chemical fertilizer, and combined applying polyaspartic acid under the premise of reducing nitrogen application by 20% can effectively increase tomato yield，improve tomato quality，and enhance nitrogen agronomy efficiency．
