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Field-Scale Time of Weed Removal in Canola

Published online by Cambridge University Press:  20 January 2017

K. Neil Harker*
Affiliation:
Agriculture and Agri-Food Canada (AAFC), Lacombe Research Centre, 6000 C&E Trail, Lacombe, Alberta, Canada T4L 1W1
John T. O'Donovan
Affiliation:
Agriculture and Agri-Food Canada (AAFC), Lacombe Research Centre, 6000 C&E Trail, Lacombe, Alberta, Canada T4L 1W1
George W. Clayton
Affiliation:
AAFC, Lethbridge Research Centre, P.O. Box 3000, Lethbridge, Alberta, Canada T1J 4B1
John Mayko
Affiliation:
Canola Council of Canada, P.O. Box 325, Mundare, Alberta, Canada T0B 3H0
*
Corresponding author's E-mail: [email protected].

Abstract

Field-scale experiments were conducted at several western Canada locations to determine the importance of early weed removal over variable landscapes. In eight of 10 cases, imidazolinone-resistant (IR) canola yield decreased linearly as herbicide application (15/15 g/ha imazamox/imazethapyr or 15/15 g/ha imazamox/imazethapyr plus 150 g/ha clopyralid) was delayed beyond the one- to two-leaf stage. In two of 10 cases, canola oil content also decreased as herbicide treatment was delayed. Canola yields at all environments (location by year combinations) averaged 2,073, 1,872, or 1,650 kg/ha when treated at the one- to two-, three- to five-, or six- to seven-leaf stage, respectively. Assuming canola prices from a low of $250/t to a high of $650/t, growers could lose $50 to $131/ha, respectively, by delaying herbicide application from the one- to two- to the three- to five-leaf stage, or $106 to $275/ha, respectively, by delaying herbicide application from the one- to two- to the six- to seven-leaf stage.

Type
Note
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Clayton, G. W., Harker, K. N., O'Donovan, J. T., Baig, M. N., and Kidnie, M. J. 2002. Glyphosate timing and tillage system effects on glyphosate-tolerant canola (Brassica napus). Weed Technol 16:124130.Google Scholar
Harker, K. N. 2001. Survey of yield losses due to weeds in central Alberta. Can J. Plant Sci 81:339342.Google Scholar
Harker, K. N., Clayton, G. W., and Johnston, A. M. 1999. Time of weed removal for canola. in Proceeding of the 10th International Rapeseed Congress. September 26 to 29, Canberra, Australia. [CD ROM]. 4.Google Scholar
Martin, S. G., Friesen, L. F., and Van Acker, R. C. 2001. Critical period of weed control in spring canola. Weed Sci 49:326333.Google Scholar
O'Donovan, J. T. 1991. Quackgrass [Agropyron repens (L.) Beauv.] interference in canola (Brassica campestris L.). Weed Sci 39:397401.Google Scholar
O'Donovan, J. T., Harker, K. N., Clayton, G. W., and Blackshaw, R. E. 2006. Comparison of a glyphosate-resistant canola (Brassica napus L.) system with traditional herbicide regimes. Weed Technol 20:494501.Google Scholar
O'Donovan, J. T., Kirkland, K. J., and Sharma, A. K. 1989. Canola yield and profitability as influenced by volunteer wheat infestations. Can. J. Plant Sci 69:12351244.Google Scholar
O'Donovan, J. T., Sharma, A. K., Kirkland, K. J., and de St. Remy, E. A. 1988. Volunteer barley (Hordeum vulgare) interference in canola (Brassica campestris and B. napus). Weed Sci 36:734739.Google Scholar
SAS Institute 1999. SAS/STAT User's Guide. Version 8. Cary, NC 27511.Google Scholar
Senseman, S. A., editor. 2007. Herbicide Handbook. 9th ed. Lawrence, KS: Weed Science Society of America. 458.Google Scholar
Swanton, C. J., Harker, K. N., and Anderson, R. L. 1993. Crop losses due to weeds in Canada. Weed Technol 7:537542.Google Scholar