Nitrogen responses and nitrogen management in potato

Innumerable experiments have been carried out to establish the yield response of potato to the rate of nitrogen (N) supply. Given the continuing change in production level of potato and because of the need to maximise the nutrient use efficiency and to reduce losses of harmful nitrogenous compounds to the environment, such research is still necessary and topical. This minireview addresses dose–response curves of fertiliser N input; the development of N fertiliser recommendation systems; the so-called three-quadrant diagram of fertiliser N response which dissects the ‘agronomic response’ into the underlying components; the concept of critical nitrogen concentration as a function of crop biomass; environmental aspects of fertiliser nitrogen supply; and the strategy of the potato plant to cope with nitrogen limitation. European legislation sets limits on the input of nitrogen and sets norms on water quality, making nitrogen use efficiency (NUE) a critical issue. Precision agriculture may help to maximise NUE, provided an adequate diagnostic system is developed that distinguishes between nitrogen deficiency and other causes of spatially divergent crop performanc