AS  Vol.6 No.3 , March 2015
Evaluation of Delayed Glyphosate Burndown in No-Till Soybean
Abstract: Application of a preplant or preemergence glyphosate burndown is routine in most no-tillage production systems of annual crops, however, time of application may influence overall weed control and grain yield. Six field trials were conducted over a three-year period (2008, 2009 and 2010) near Ridgetown, Ontario, Canada to determine the effect of glyphosate burndown application timing in glyphosate-resistant (GR) no-tillage soybean [Glycine max (L.) Merr.]. Soybean growth was reduced 5%, 10% and 20% when the burndown was delayed to 1, 5 and 12 days after planting (DAP), when evaluated one week after application (WAA), respectively. By 8 WAA, predicted burndown timing increased to 9, 14 and 23 DAP, and was 10, 17 and 26 DAP at 12 WAA, to reduce soybean growth by 5%, 10% and 20%, respectively. Similarly, burndown application at 14, 21 and 30 DAP corresponded to a soybean yield reduction of 5%, 10% and 20%. Seed moisture content was generally insensitive to burndown timing; 80 and 140 DAP were required to increase moisture by 5% and 10%, respectively. This research indicates that delaying glyphosate burndown by up to 14 DAP, approximately VE to VC growth stage, has the potential to result in a modest reduction in soybean yield (5%).
Cite this paper: Belfry, K. , Shropshire, C. and Sikkema, P. (2015) Evaluation of Delayed Glyphosate Burndown in No-Till Soybean. Agricultural Sciences, 6, 346-351. doi: 10.4236/as.2015.63035.

[1]   Statistics Canada (2014) Production of Principle Field Crops, September 2014.

[2]   Kulasekera, K. (2014) Estimated Area, Yield, Production and Farm Value of Specified Field Crops, Ontario, 2011-2013. Ontario Ministry of Agriculture, Food and Rural Affairs.

[3]   Beckie, H.J. (2006) Herbicide-Resistant Weeds: Management Tactics and Practices. Weed Technology, 20, 793-814.

[4]   Duke, S.O. and Powles, S.B. (2008) Glyphosate: A Once-in-a-Century Herbicide. Pest Management Science, 64, 319-325.

[5]   Beckie, H.J., et al. (2006) A Decade of Herbicide-Resistant Crops in Canada. Canadian Journal of Plant Science, 86, 1243-1264.

[6]   Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) (2013) Guide to Weed Control 2014-2015: Publication 75. Queen’s Printer for Ontario, Toronto.

[7]   Owen, M.D. (2008) Weed Species Shifts in Glyphosate-Resistant Crops. Pest Management Science, 64, 377-387.

[8]   Marra, M.C., Piggott, N.E. and Carlson, G.A. (2004) The Net Benefits, Including Convenience, of Roundup Ready? Soybeans: Results from a National Survey, Technical Bulletin 2004-3. NSF Center for Integrated Pest Management, Ralieigh.

[9]   Gonzini, L.C., Hart, S.E. and Wax, L.M. (1999) Herbicide Combinations for Weed Management in Glyphosate-Resistant Soybean (Glycinemax). Weed Technology, 13, 354-360.

[10]   Van Acker, R.C., Swanton, C.J. and Weise, S.F. (1993) The Critical Period of Weed Control in Soybean [Glycinemax (L.) Merr.], Weed Science, 41, 194-200.

[11]   Vangessel, M.J., Ayeni, A.O. and Majek, B.A. (2000) Optimum Glyphosate Timing with or without Residual Herbicides in Glyphosate-Resistant Soybean (Glycine max) under Full-Season Conventional Tillage, Weed Technology, 14, 140-149.[0140:OGTWOW]2.0.CO;2

[12]   Seefeldt, S.S., Jensen, J.E. and Fuerst, E.P. (1995) Log-Logistic Analysis of Herbicide Dose-Response Relationships. Weed Technology, 9, 218-227.

[13]   Bowley, S. (1999) A Hitchhiker’s Guide to Statistics in Plant Biology. AnyOldSubjectBooks, Guelph.

[14]   Vangessel, M.J., Ayeni, A.O. and Majek, B.A. (2001) Glyphosate in Full-Season No-Till Gly-phosate-Resistant Soybean: Role of Preplant Applications and Residual Herbicides. Weed Technology, 15, 714-724.[0714:GIFSNT]2.0.CO;2

[15]   Tharp, B.E. and Kells, J.J. (2001) Delayed Burndown in No-Tillage Glyphosate-Resistant Corn (Zea mays) Planted into Soybean (Glycine max) Residue and a Wheat (Triticum aestivum) Cover Crop. Weed Technology, 15, 467-473.[0467:DBINTG]2.0.CO;2

[16]   Cox, W.J., Hahn, R. and Stachowski, P.J. (2006) Time of Weed Removal with Glyphosate Affects Corn Growth and Yield Components. Agronomy Journal, 98, 349-353.

[17]   Mulugeta, D. and Boerboom, C.M. (2000) Critical Time of Weed Removal in Glyphosate-Resistant Glycinemax. Weed Science, 48, 35-42.[0035:CTOWRI]2.0.CO;2

[18]   Swanton, C.J., Shrestha, A., Chandler, K. and Deen, W. (2000) An Economic Assessment of Weed Control Strategies in No-Till Glyphosate-Resistant Soybean (Glycinemax). Weed Technology, 14, 755-763.[0755:AEAOWC]2.0.CO;2

[19]   Johnson, W.G., Gibson, K.D. and Conley, S.P. (2007) Does Weed Size Matter? An Indiana Grower Perspective about Weed Control Timing. Weed Technology, 21, 542-546.