Centipedegrass Tolerance to Postemergence Grass Herbicides

Abstract

Abstract The phytotoxicity of single and sequential treatments of sethoxydim and fluazifop at 0.10, 0.20, and 0.30 kg·ha −1 ; haloxyfop, xylafop, fenoxaprop, and SC-1084 at 0.07, 0.15, and 0.30 kg·ha −1 , on centipedegrass [ Eremochloa ophiuroides (Munro.) Hack.] was determined. Turf color generally was unaffected by sethoxydim application except for a slight discoloration at 14 days after treatment (DAT) with the high rate. Recovery was evident from all rates of sethoxydim by 28 DAT. Turf density was similar to untreated control at 42 DAT. Single applications of fenoxaprop and SC 1084 at 0.07 kg·ha −1 initially caused severe discoloration; however, recovery was evident by 42 DAT. Density also was unaffected at this time. Unacceptable turf color and density were observed with single and sequential applications of fluazifop, haloxyfop, xylafop, and with sequential application of SC 1084 and fenoxaprop. Chemical names used: (2-[l-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-l-one (sethoxydim); (±)-2-[4-[[5-(trifluoromethyl)-2-pyridinyl]oxyl]phenoxy]propanoic acid (fluazifop); 2-[4-[[3-chloro-5-(trifluoromethyl)-2-pyridinyl]oxy]-phenoxyl]propanoic acid (haloxyfop); (2-[4-[(6-chloro-2-quinoxalinyl)-oxy]phenoxyl]propanoic acid (xylafop); (±)-2-[4-[(6-chloro-2-benzoxazolyl)oxy]phenoxy]propanoic acid (fenoxaprop); and methyl-3-hydroxy-4-[4-[[5-(trifluoromethyl)-2-pyridinyl]oxy]phenoxy]-pentanoate (SC-1084).