ABSTRACT

The unnecessary application of nitrogen could negatively impact both the yield and quality of crops, and could also lead to nitrate leaching and soil pollution. The objective of this study was to investigate the effects of the optimized nitrogen application on ¹⁵N accumulation, utilization and distribution of processing tomato in China. Through field experiments with ¹⁵N and consisted two treatments: optimized nitrogen application (NY) and no nitrogen application (N0). The results showed that the absorption efficiency of applied fertilizer nitrogen was 46%. In processing tomato plants, 128.9 kg ha⁻¹ of nitrogen came from applied fertilizer, while the remainder of the nitrogen (177.6 kg ha⁻¹) came from the soil. The processing tomato fully absorbed the soil nitrogen, which reduced the nitrogen loss rate and resulted in higher production of dry matter. In the harvest stage. The residual percentage in soil of applied fertilizer nitrogen was 34%, which was mainly distributed in the 0-40 cm soil layer. This reduced the leaching of nitrogen and was conducive to the reuse of crops in the next year. This study provides a reference for the development of precise nitrogen management techniques using drip irrigation methods in arid areas..