The aim of this study is to improve potato crop yields in the Loukkos region, which is characterised by nutrient-poor soil, through a trial designed to study the crop's response to different doses of nitrogen, phosphorus and potassium fertilisers, and to rationalise the use of these nutrients (N, P, K) on potato crops while maintaining good plant mycorrhisation in order to obtain all the benefits of this association. We studied the effect of 32 fertilisation treatments (N and P), applied at different stages of potato development, on mycorrhizal load. The yield and grading of harvested potato tubers were the two main parameters used to assess the crop's response to fertilisation. The results show that the X2 nitrogen, X3 phosphorus and X2 potassium (2 3 2) treatments produced the highest yields while maintaining good plant mycorrhization.