Modified heptamethylhexane polyalkyleneoxide, ethoxylated isodecyl ale. and methylated rape oil ester were added as adjuvants to the halved dose of the corn. herbicide and then used as a spray liq. to control Echinochloa crus-galli L. under greenhouse conditions. Addnl., citric acid, AcOH as well as aq. NH3 and K3PO4 solns. were added to the figs. to modify their pH value to 4 or 9, resp. For comparison, the spray lips. contg. only the studied herbicide in the full dose (150 g/ha) or in reduced dose (75 g/ha) were also tested. Measurements of surface tension and adhesion angle of the spray liq. droplets were detd. for each chem. compn. of the liq. Addnl., a visual evaluation of the herbicide action was carried out 21 days after application of the spray. The highest control efficiency of Echinochloa crusgalli plant was achieved for the liq. with the adjuvant. The pH value of the spray liquid tested had major impact on its effectiveness.