Effect of different rates and methods of application of NPK-fertilizers on the quality of potato tubers

Research on the effect of different rates and methods of application of mineral NPK fertilizers on the quality of potato variety 'Carrera' was conducted on a luvisol of the Radocelo Mountain massif. Treatments included an unfertilized control, NPK 16:16:16 (1500 kg/ha) applied in-furrow at planting, NPK 16:16:16 (1200 kg/ha) applied in-furrow at planting, and NPK 16:16:16 applied at 700 kg/ha during seedbed preparation and at 500 kg/ha in-furrow at planting. Results on the nutritional value of potato tubers showed that the levels of tested nutrients were higher in the skin than in the flesh. The concentrations of tested nutrients in potato tubers were highest at the highest NPK fertilizer rate, whereas the lowest levels of all nutrients, except Fe, were determined in tubers at NPK rates of 700 kg/ha applied pre-plant and 500 kg/ha applied at planting.