A greenhouse study was conducted in the Department of Agronomy and Plant Breeding, Mohaghega Ardabili, University of Ardabil, Iran during 2012 to determine the efficacy of 3 adjuvants (citogate, castor oil and canola oil) at concentrations of 0, 0.1 and 0.2 (%v/v) with mixture of metsulfuron methyl and sulfosulfuron (Total®) herbicide @ 4, 10, 20, 30 and 40 g. a.i to control littleseed canary grass (Phalaris minor Ritz.). Results showed that all adjuvants enhanced the efficacy of Total® in decreasing the dry weights of littleseed canary grass. Performance of herbicide increased with enhancing their concentrations against the tested plant. Measured ED50 and ED90 doses of Total® alone based on littleseed canary grass dry weight were 17.61 and 34.27 g a.i./ha, respectively. Whereas values for citogate 0.2 (%v/v), were 6.03 and 14.27 g a.i/ha, respectively. The addition of citogate and canola oil had the highest and lowest effect on Total® efficacy against littleseed canary grass, respectively, supporting the idea that this adjuvant solubilizes the cuticular waxes thus facilitating herbicide uptake.

Keywords