Effects of coated urea replacing water-soluble nitrogen fertilizer on the yield and quality of greenhouse tomato

LI Quanhui; ZHAO Kaili; GUO Ning; YIN Xinxin; SHI Wenxue

doi:10.16861/j.cnki.zggc.2024.0486

Abstract：In order to explore the effect of controlled release nitrogen fertilizer as a substitute for water-soluble nitrogen fertilizer,a spring tomato experiment was carried out in greenhouse in the suburbs of Beijing.The effects of four fertilization methods,namely conventional fertilizer(FP),optimal fertilizer(OPT),50％coated urea replacing(CU50),and 100％coated urea replacing(CU1 00),on tomato yield,quality,nutrient absorption and soil nitrate nitrogen residue were studied.The results showed that the yield of FP(30.8 t·hm-2)was the lowest,followed by CU100 and OPT treatments,while the CU50 treatment had the highest yield(35.6 t·hm-2),which was significantly 15.9％higher than FP and 1.6％higher than OPT.The output value and net income also showed a similar pattern of change.The output value and net income of CU50 treatment were significantly higher than the other treatments,with a significant increase of 11 000 yuan·hm-2 and 14 000 yuan·hm-2 compared with the OPT treatment,respectively.The vitamin C content in tomato fruit was highest in the CU50 treatment,but there was no significant difference between CU50,OPT,and FP treatments.The nitrate content was lowest in the CU1 00,followed by CU50,both of which were significantly lower than FP and OPT.After the harvest,the residual amount of nitrate nitrogen in soil treated with CU50 was the lowest,followed by CU100,both of which were significantly lower than FP and OPT.The nutrient uptake of N,P,K by tomato plants,as well partial productivity of K fertilizer,were high-est in CU50,significantly higher than other treatments.There was no surplus of nitrogen,phosphorus and potassium nutri-ents in CU50 and CU100.In summary,the recommended fertilizer amount for spring greenhouse tomatoes is 42.3 kg·hm-2 of phosphorus,and 171.6 kg·hm-2 of potassium.By adjusting the water nitrogen coupling while keeping the traditional nitrogen application of 128.4 kg·hm-2 basically unchanged,using coated urea application instead of 50％water-soluble nitrogen application could improve both yield and quality.