GROWTH AND YIELD OF GARDEN ROCKET (Eruca sativa. Mill.) AFFECTED BY NITROGEN AND POTASSIUM FERTILIZATION

We studied the effect of differentiated nitrogen-potassium fertilization upon the growth, yield and chemical composition of garden rocket leaves grown in unheated greenhouse in autumn. Two nitrogen doses were applied (0.3 and 0.6 g dm(-3)) in the form of calcium saltpeter and two doses of potassium (0.3, 0.6 and 0.9 g dm(-3)) in the form of chloride and sulfate. The increased amounts of nitrogen and potassium generally contributed to the increase of fresh leaf weight yield. Plants nourished with KCl had larger concentrations of L-ascorbic acid, chlorine and calcium, whereas the contents of protein, sugars in total, as well as sulfates were smaller, as compared to plants nourished with K(2)SO(4).