Dr hab. inż. Ewa Stanisławska-Glubiak, prof. nadzw., mgr inż. Sylwia Gołda, Department of Weed Science and Soil Tillage Systems in Wroclaw, Institute of Soil Science and Plant Cultivation - State Research Institute in Pulawy, Orzechowa 61 St., 50-540 Wroclaw, Poland, phone: +48 71 3638707