Arugula is a common name that refers to several leafy vegetable species of the family Brassicaceae. Diplotaxis tenuifolia (L.) D.C. and Eruca sativa Mill. have gained the greatest economic importance. The aim of this study was to determine the effect of plant covering with perforated polyethylene (PE) film and non-woven polypropylene (PP) fabric on the concentrations of micronutrients, heavy metals and nitrates in arugula leaves. A two-factorial experiment was conducted in the Experimental Garden of the University of Warmia and Mazury in Olsztyn. The experimental factors were two plant species: D. tenuifolia and E. sativa, and two types of plant cover: perforated PE film with 100 openings per m2 and non-woven PP fabric with surface density of 17 g m-2. In the control treatment, plants were grown without any covers. Each year, seeds were sown in mid-April. Immediately after seeding, the plots were covered with PE film or non-woven PP fabric. The covers were removed after approximately five weeks. Mineral content was determined in dry plant material collected at first harvest. The content of cadmium (Cd), lead (Pb), nickel (Ni), copper (Cu), chromium (Cr), zinc (Zn) and manganese (Mn) was determined by atomic absorption spectrometry (AAS), and Zn:Cu and Mn:Zn weight ratios were calculated. The concentrations of all analyzed heavy metals (including micronutrients) in arugula leaves were affected by both plant species and cover type. The leaves of E. sativa had a higher content of Cd, Pb, Ni, Cu, Cr, Zn and Mn. The use of covers contributed to a decrease in the accumulation levels of micronutrients and heavy metals in the edible parts of arugula plants. A widened Zn:Cu ratio was noted in all treatments, whereas Mn:Zn ratios were regarded as too narrow, relative to the normal ranges. The concentrations of nitrates (V) were higher in the leaves of D. tenuifolia. Plants of both species covered with non-woven PP fabric accumulated the highest levels of nitrates(V).

26.2.2021