Authors: Sevil AĞAR, Richard M. WILKINS
Abstract: In this study, It was determined the effect of adjuvant oils on the growth of plants, for this purpose, Black grass (Alopecurus myosuroides Hudson.) grown in greenhouse conditions was treated with the post-emergence herbicide fenoxaprop-p-ethyl at two dosages (55 g Al. ha^-1, 45g Al. ha^-1). In addition, soybean oil and soybean oil methyl ester were emülsified by the non-ionic compound Triton X-100 at 5 % (v/v). These adjuvants were added to the herbicide and they were applied at 0.1 % (v/v), 1 % (v/v) and 5 % (v/v). Their influence on the biological activity of herbicides was observed. The retention of the herbicide solutions was measured by Shimadzu Spectrofluorophotometer using a fluorescent dye (0.01 %) and surface tension of solutions was determined by torsion balance. Surface tension of fenoxaprop-p-ethyi solution was 34.2-34.3 mM. m^-1 and was not modifield by and of adjuvant that used in this study. Addition of soybean oil and soybean oil methyl ester increased the herbicidal activity (especially at 5 % v/v) and they gave an increase in retention (15.15/mul. g^-1 for fenoxaprop-p-ethyl without adjuvant, 23.20/mul.g^-1 for soybean oil, 25.20mul. g^-1 for its methyl ester) although the surface tension was unaltered.