Superoxide dismutase (SOD), guaiacol peroxidase (g-pox) and catalase (CAT) activities in the barley (a,c,e) and pea (b,d,f) seedlings after 3 days of growth, watered with tap water (control: B/P-C), plasma-activated water (PAW) of glow discharge with water cathode and treatment time 1 and 2 min (B/P-GD1 and B/P-GD2), PAW of transient spark discharge with electrospray (B/P-TS) and 2-mM nitric acid (B/P-N). Values are shown as mean ± SD from three experimental rounds, in each round (one run represents five seedlings per variant, 1.5 g mixed samples were analysed per one experimental run and each variant for SOD, G-POX and CAT activity). Different letters represent statistically significant difference at p < 0.05 according to LSD test.