Blackshaw, R.E.

Harker, N.H.

O'Donovan, J.T.

Strelkov, S.S.

Tozzi, E.

Willenborg, C.J.

English

University of Saskatchewan Research Archive

Late glyphosate applications alter yield and yield components in glyphosate-resistant canola (Brassica napus L.)E. Tozzi1, N.H. Harker2, R.E. Blackshaw3, J.T. O’Donovan2, S.S. Strelkov2, and C.J. Willenborg11University of Saskatchewan2University of Alberta 3Agriculture and Agri-Food CanadaBackground90% of all canola grow in Canada is GM (Beckie et al. 2011)- 48% is glyphosate-resistant (Beckie et al. 2011)Early/On-label glyphosate applications = optimal yields (Clayton et al. 2002)Crop injury from late glyphosate applications in cotton and soybean (Pline et al. 2002, Krausz and Young 2001)Increasingly wet weather during growing season in the Prairies since 2010 (Environment Canada, 2015)ObjectiveDetermine effects of late or sequential herbicide applications of glyphosate on glyphosate-resistant canola yield and yield components.Slide 2 of 213Materials and MethodsLacombe, Alberta 2010-2012St. Albert, Alberta from 2010-2011 Lethbridge, Alberta from 2011-2012 Saskatoon, Saskatchewan in 2012Canola 45H28 (RR) Plots were hand weededRCBD4 reps/treatmentPlot size 2 x 6 mStubble (St. Albert, Lethbridge)Fallow (Lacombe, Saskatoon)two-leaf (2L), six-leaf (6L) ,bolt (B), early bloom (EB),2L&6L, 2L&B, 2L&EB• Yield• Seeds/Pod• Aborted Pods• Thousand-Seed Weight (TSW)Data CollectionSt. Albert 2010 - Yield19%Lethbridge 2011 - Yield34%Lethbridge 2012 - Yield16%Contrasts - YieldSt. Albert 2010 – Seeds/pod23%St. Albert 2011 – Seeds/pod12%Lethbridge 2011 – Seeds/pod11%St. Albert 2010 – TSW31%Lethbridge 2011 - TSW11%St. Albert 2010 – Aborted Pods76%St. Albert 2011 – Aborted Pods52%Lethbridge 2012 – Aborted Pods42%Discussion• Stubble (St. Albert, Lethbridge) vs. Fallow (Lacombe, Saskatoon)• Local Seasonal Weather –site/year differences• Taco Bell?Conclusion• Potential for reduced tolerance in GR canola to late and sequential applications• Possible significant economic impact (~20bu/ac)• Important to stay on-label• Yield effects if late or sequential applications are needed

Late glyphosate applications alter yield and yield components in glyphosate-resistant canola (Brassica napus L.)

eCommons@USASK

https://harvest.usask.ca/bitstream/10388/8884/1/E.%20Tozzi%20et%20al.%2c%202015.pdf

Late glyphosate applications alter yield and yield components in glyphosate-resistant canola (Brassica napus L.)

Abstract

Similar works

Full text

Available Versions

University of Saskatchewan Research Archive

eCommons@USASK