Effect of dripper fertigation on tomato yield and apparent N balance in a greenhouse

Conventional water and fertilizer management for greenhouse vegetable crops results in soil nitrate accumulation and severe leaching, groundwater contamination and heavy occurrence of soil borne plant pathogens, which have been attributed to higher input of fertilizer and much frequent flooding irrigation. In the present study, two irrigation/fertilization systems were compared in a greenhouse experiment conducted in Shouguang, Shandong. Results showed that the fertigation with a dripper system increased production of tomato yield by 19.6%, compared with the conventional system. During a whole growing season, 36% of water and 80% of nitrogen were saved. And total economic input was 18 percent lower and net benefit reached to an increase by 33%. The nitrate accumulation in the soil profile (090 cm) depth was N 107551 kg /ha for conventional production system and N 57246 kg/ha for dripper fertilization system, while N 99961 and -4640 kg/ha was not recovered and thought to be lost from the both systems respectively.