EN
In 2007–2008 field experiments were conducted to estimate the biological activity of glyphosate (Roundup 360 SL) against Agropyron repens and broad-leaved weed species on stubble and barren land. The herbicide was applied with some additives (Superzwilżacz, water glass) and water conditioner adjuvants (X-Change, Niagara, ammonium sulfate, AS 500 SL) at two spray volumes 130 and 260 l/ha, respectively. For treatments different spray quality (water distilled, standard tap water – 13,4°n, hard water – 33,4°n) was used. The best results were obtained when glyphosate with addition of ammonium sulfate or AS 500 SL was applied, regardless of water quality used for the dilution of herbicide. Effect on weeds was better when herbicide was applied with hard water. The addition of water conditioner, especially X-Change increased glyphosate activity against A. repens and other weed species. The efficiency of glyphosate against weeds was higher with the use of the lower spray volume 130 l/ha comparing to the treatments with spray volume of 260 l/ha.