Influence of fluorinated surfactants on the efficacy of some post-emergence sulfonyluera herbicides

• Published in: Journal of pesticide science (2003) Vol. 32; no. 1
• Main Authors: Stagnari, F.(University of Teramo (Italy)), Chiarini, M, Pisante, M
• Format: Journal Article
• Language: English
• Published: 01.02.2007
• Subjects: ADJUVANT; ADJUVANTS; COADYUVANTES; HERBICIDAS; HERBICIDE; HERBICIDES; MALEZAS; MAUVAISE HERBE; SULFONILUREAS; SULFONYLUREE; SULPHONYLUREAS; WEEDS
• ISSN: 1348-589X; 1349-0923

Fluorinated non-ionic surfactants were assessed as adjuvants for tribenuron-methyl, triflusulfuron-methyl and foramsulfuron. The compared adjuvants included hydroxy-terminated fluorinated polyether (PF-151N), polyoxyethylene-alpha-fluoro-omega-(2-hydroxyethyl)poly(difluoromethylene) (Zonyl FSN-100), and polyoxyethylene(23) lauryl ether (Brij 35). Greenhouse experiments were performed to evaluate these surfactants both for their efficacy in controlling weeds and selectivity to crops. Tribenuron-methyl and triflusulfuron-methyl absorption into catchweed and giant foxtail leaves due to surfactant addition was also estimated. Zonyl FSN-100 and Brij 35 allowed a reduction in the application rate of triflusulfuron-methyl to nearly 1/2 of the labelled rate to control redroot pigweed. The foramsulfuron rate was reduced by more than 50% to control barnyardgrass thanks to the addition of Zonyl FSN-100 and it controlled giant foxtail only applied at the maximum labelled rate and mixed with Zonyl FSN-100. Tribenuron-methyl activity against poppy was only slightly enhanced by the use of adjuvants. Tribenuron-methyl efficacy was clearly enhanced by the use of adjuvants to control catchweed; however, the required dose was not lower than the labelled one. The addition of adjuvants induced slight phytotoxicity in the crops. Brij 35 caused the greatest absorption of triflusulfuron-methyl into giant foxtail leaves and of tribenuron-methyl into catchweed leaves.