THE INFLUENCE OF THE METHOD OF PRODUCTION ON THE CONTENT OF MINERAL SUBSTANCES AND NITRATES IN LETTUCE

The lettuce is a very good and inexpensive source of minerals (N, P, K), but in the winter it is prone to accumulation of toxic substances (nitrates). The main goal of our research is to examine the impact of new technologies of production (land cover) on the quality of lettuce produced in the winter. Mineral content varied depending on the mode of production. The values of nitrogen content in lettuce tend to rise from bare ground (2.89-4.58%) to covered (3.09-4.85%) soil. The type of material that covers the land also has an impact on the content of potassium. The applied versions of the cover did not significantly affect the phosphorus content. There is a trend of nitrate increase when applying different methods of production.