high-input systems; nevertheless, plant responses to nitrogen fertilization, in terms of the effects on dry matter production and allocation to different plant organs, have yet to be investigated in depth. Moreover, information on the crop marginal net return and global warming potential (as an index of the environmental impact of crop cultivation) at different nitrogen rates is still scarce. Therefore, the aim of this work was to study the effects of different nitrogen rates (0, 50, 100, 150, 200, and 250 kg of N ha−1) on the agronomic, economic, and environmental aspects of processing tomato grown under conventional management in the Mediterranean area. The results of the two-year trials indicated 200 kg of nitrogen ha−1 as the best rate,...