EFFECTS OF NITROGEN AND POTASSIUM FERTILIZATION ON GROWTH, YIELD AND CHEMICAL COMPOSITION OF GARDEN ROCKET

Abstract. Plants of the family Brassicaceae are characterized by high nutritional and fer-tilization requirements, in particular with respect to nitrogen, potassium, and sulphur. The positive action of the above-mentioned nutrients on plant growth and yield is associated, among others, with their rate and form as well as with interrelationships between individ-ual nutrients. The present experiment was conducted in a greenhouse during the period from March to May in the years 2010 and 2011. Garden rocket plants were seeded indi-vidually in 2dm3 pots, with peat as the growing medium. The experimental design in-cluded three rates (g dm-3 of medium) of potassium in the form of K2SO4: 0.3 K (and 0.34 S); 0.6 K (and 0.47 S); 0.9 K (and 0.6 S), in the form of KCl: 0.3 K (and 0.27 Cl); 0.6 K (and 0.54 Cl); 0.9 K (and 0.81 Cl), as well as two rates of nitrogen in the form of Ca (NO3)2: 0.3 N (and 0.37 Ca); 0.6 N (and 0.74 Ca). The following traits were deter-mined: plant height (cm), number of leaves per rosette (pcs), plant weight (g), and fresh weight yield of leaf rosettes (g. pot-1). The content of N, P, K, Ca and of Mg, S-SO4, Cl was determined in dried plant material. The increase in the rate of nitrogen in the nutri-tional environment of rocket did not affect plant height and the number of leaves per ro