Author
Price, Andrew | |
Koger Iii, Clifford | |
WILCUT, J - N.C. STATE UNIVERSITY | |
MILLER, D - LOUISIANA STATE UNIV. | |
VAN SANTEN, EDZARD - AUBURN UNIVERSITY |
Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/3/2008 Publication Date: 10/1/2008 Citation: Price, A.J., Koger III, C.H., Wilcut, J.W., Miller, D., Van Santen, E. 2008. Efficacy of residual and non-residual herbicides used in cotton production systems when applied with glyphosate, glufosinate, or MSMA. Weed Technology. 22:459-466. Interpretive Summary: Field experiments were conducted to evaluate weed control provided by glyphosate, glufosinate, and MSMA applied alone or in mixture with residual and non-residual LAYBY herbicides. Herbicide treatments included glyphosate early postemergence alone or followed by: 1) glyphosate, 2) glufosinate, or 3) MSMA late-postemergence alone or tank mixed with one of the following layby herbicides: 4-7) carfentrazone-ethyl 8-11) diuron, 12-15) flumioxazin, 16-19) fluometuron, 20-23) lactofen, 24-27) linuron, 28-31) oxyfluorfen, 32-35) prometryn, or 36-39) prometryn + trifloxysulfuron. Residual herbicides were also applied alone LPOST. Treatments containing MSMA provided lower average weed control compared to those containing glyphosate or glufosinate, and residual herbicides applied alone provided inadequate weed control compared to mixtures containing a non-residual herbicide. Across 315 of 567 comparisons (55%), when a LAYBY herbicide was added, weed control increased. Technical Abstract: Field experiments were conducted to evaluate weed control provided by glyphosate, glufosinate, and MSMA applied alone or in mixture with residual and non-residual LAYBY herbicides. Herbicide treatments included glyphosate early postemergence (EPOST) alone or followed by: 1) glyphosate, 2) glufosinate, or 3) MSMA late-postemergence (LPOST) alone or tank mixed with one of the following layby herbicides: 4-7) carfentrazone-ethyl at 0.3 kg ai/ha, 8-11) diuron at 1.12 kg ai/ha, 12-15) flumioxazin at 0.07 kg ai/ha, 16-19) fluometuron at 1.12 kg ai/ha, 20-23) lactofen at 0.84 kg ai/ha, 24-27) linuron at 0.56 kg ai/ha, 28-31) oxyfluorfen at 1.12 kg ai/ha, 32-35) prometryn at 1.12 kg ai/ha, or 36-39) prometryn + trifloxysulfuron at 1.12 kg ai/ha + 10 g ai/ha. Residual herbicides were also applied alone LPOST. Weeds evaluated included barnyardgrass, broadleaf signalgrass, coffee senna, entireleaf morningglory, hemp sesbania, ivyleaf morningglory, johnsongrass, large crabgrass, Palmer amaranth, pitted morningglory, prickly sida, redroot pigweed, sicklepod, smooth pigweed, spiny amaranth, and velvetleaf. Treatments containing MSMA provided lower average weed control compared to those containing glyphosate or glufosinate, and residual herbicides applied alone provided inadequate weed control compared to mixtures containing a non-residual herbicide. Across 315 of 567 comparisons (55%), when a LAYBY herbicide was added, weed control increased. The most difficult to control weed species at all locations was pitted morningglory. Barnyardgrass and hemp sesbania at the Mississippi location and hemp sesbania at the Louisiana location were collectively difficult to control across all treatments as well. |