Skip to main content Accessibility help

Glyphosate-resistant wheat persistence in western Canadian cropping systems

  • K. Neil Harker, George W. Clayton (a1), Robert E. Blackshaw (a2), John T. O'Donovan (a3), Eric N. Johnson (a4), Yantai Gan (a5), Frederick A. Holm (a6), Ken L. Sapsford (a6), R. Byron Irvine (a7) and Rene C. Van Acker (a8)...


As a weed, wheat has recently gained greater profile. Determining wheat persistence in cropping systems will facilitate the development of effective volunteer wheat management strategies. In October of 2000, glyphosate-resistant (GR) spring wheat seeds were scattered on plots at eight western Canada sites. From 2001 to 2003, the plots were seeded to a canola–barley–field-pea rotation or a fallow–barley–fallow rotation, with five seeding systems involving seeding dates and soil disturbance levels, and monitored for wheat plant density. Herbicides and tillage (in fallow systems) were used to ensure that no wheat plants produced seed. Seeding systems with greater levels of soil disturbance usually had greater wheat densities. Volunteer wheat densities at 2 (2002) and 3 (2003) yr after seed dispersal were close to zero but still detectable at most locations. At the end of 2003, viable wheat seeds were not detected in the soil seed bank at any location. The majority of wheat seedlings were recruited in the year following seed dispersal (2001) at the in-crop, prespray (PRES) interval. At the PRES interval in 2001, across all locations and treatments, wheat density averaged 2.6 plants m−2. At the preplanting interval (PREP), overall wheat density averaged only 0.2 plants m−2. By restricting density data to include only continuous cropping, low-disturbance direct-seeding (LDS) systems, the latter mean dropped below 0.1 plants m−2. Only at one site were preplanting GR wheat densities sufficient (4.2 plants m−2) to justify a preseeding herbicide treatment in addition to glyphosate in LDS systems. Overall volunteer wheat recruitment at all spring and summer intervals in the continuous cropping rotation in 2001 was 1.7% (3.3 plants m−2). Despite the fact that volunteer wheat has become more common in the central and northern Great Plains, there is little evidence from this study to suggest that its persistence will be a major agronomic problem.


Corresponding author

1 Corresponding author. Agriculture and Agri-Food Canada, Lacombe Research Centre, 6000 C & E Trail, Lacombe, AB T4L 1W1, Canada;


Hide All
Amor, R. L. and Francisco, T. M. 1987. Survey of weeds in field peas, chickpeas and rapeseed in the Victorian Wimmera. Plant Protect. Q 2:124127.
Anderson, R. L. and Nielsen, D. C. 1996. Emergence pattern of five weeds in the Central Great Plains. Weed Technol 10:744749.
Anderson, R. L. and Soper, G. 2003. Review of volunteer wheat (Triticum aestivum) seedling emergence and seed longevity in soil. Weed Technol 17:620626.
Beckie, H. J., Hall, L. M., and Warwick, S. I. 2001. Impact of herbicide-resistant crops as weeds in Canada. Proc. Br. Crop Prot. conf.— Weeds. Pp. 135142.
Blackshaw, R. E. and Harker, K. N. 2002. Selective weed control with glyphosate in glyphosate-resistant wheat (Triticum aestivum). Weed Technol 16:885892.
Blackshaw, R. E., Harker, K. N., Clayton, G. W., and O'Donovan, J. T. 2006. Broadleaf herbicide effects on clethodim and quizalofop-P efficacy on volunteer wheat (Triticum aestivum). Weed Technol. In press.
Blackshaw, R. E., Larney, F. J., Lindwall, C. W., Watson, P. R., and Derksen, D. A. 2001. Tillage intensity and crop rotation affect weed community dynamics in a winter wheat cropping system. Can. J. Plant Sci 81:805813.
Budd, E. G. 1995. The control of blackgrass and volunteer wheat in perennial ryegrass grown for seed. Proc. Brighton Crop Prot. conf.— Weeds. Pp. 937942.
Campbell, C. A., Zentner, R. P., Gameda, S., Blomert, B., and Wall, D. D. 2002. Production of annual crops on the Can. prairies: trends during 1976–1998. Can. J. Soil Sci 82:4557.
Cardina, J. and Sparrow, D. H. 1996. A comparison of methods to predict weed seedling populations from the soil seed bank. Weed Sci 44:4651.
Cussans, G. W. 1978. The problem of volunteer crops and some possible means of their control. in Proceedings of the 1978 British Crop Protection conference—Weeds. Brighton, UK: British Crop Protection Council. Pp. 915921.
Derksen, D. A., LaFond, G. P., Thomas, A. G., Loeppky, H. A., and Swanton, C. J. 1993. The impact of agronomic practices on weed communities: tillage systems. Weed Sci 41:409417.
Derksen, D. A., Thomas, A. G., Lafond, G. P., Loeppky, H. A., and Swanton, C. J. 1994. Impact of agronomic practices on weed communities: fallow within tillage systems. Weed Sci 42:184194.
Friesen, L., Morrison, I. N., Marshall, G., and Rother, W. 1990. Effects of volunteer wheat and barley on the growth and yield of flax. Can. J. Plant Sci 70:11151122.
Harker, K. N., Clayton, G. W., Blackshaw, R. E., O'Donovan, J. T., Lupwayi, N. Z., Johnson, E. N., Gan, Y., Zentner, R. P., Lafond, G. P., and Irvine, R. B. 2005. Glyphosate-resistant spring wheat production system effects on weed communities. Weed Sci 53:451464.
Hilhorst, H. W. M. and Toorop, P. E. 1997. Review on dormancy, germinability, and germination in crop and weed seeds. Adv. Agron 61:111165.
Hu, T., Metz, S., Chay, C., Zhou, H. P., Biest, N., Chen, G., Cheng, M., Feng, X., Radionenko, M., Lu, F., and Fry, J. 2003. Agrobacterium-mediated large-scale transformation of wheat (Triticum aestivum L.) using glyphosate selection. Plant Cell Rep 21:10101019.
Komatsuzaki, M. and Endo, O. 1996. Seed longevity and emergence of volunteer wheat in upland fields. Weed Res. Jpn 41:197204.
Leeson, J. Y., Thomas, A. G., Hall, L. M., Brenzel, C. A., Andrews, T., Brown, K. R., and Van Acker, R. C. 2005. Prairie weed surveys of cereal, oilseed and pulse crops from the 1970s to the 2000s. Saskatoon, Canada: Agriculture and Agri-Food Canada Weed Survey Series 05-1, 395 p.
Littel, R. C., Milliken, G. A., Stroup, W. W., and Wolfinger, R. D. 1996. SAS System for Mixed Models. Cary, NC: Statistical Analysis Systems Institute. 656 p.
Lyon, D. J., Bussan, A. J., Evans, J. O., Mallory-Smith, C. A., and Peeper, T. F. 2002. Pest management implications of glyphosate-resistant wheat (Triticum aestivum) in the western United States. Weed Technol 16:680690.
Marshall, G., Morrison, I. N., Friesen, L., and Rother, W. 1989. Effects of ‘volunteer’ wheat and barley on the growth and yield of rapeseed. Can. J. Plant Sci 69:445453.
Mohler, C. L. 1993. A model of the effects of tillage on emergence of weed seedlings. Ecol. Appl 3:5373.
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.
Ogg, A. G. Jr. 1993. Control of downy brome (Bromus tectorum) and volunteer wheat (Triticum aestivum) in fallow with tillage and pronamide. Weed Technol 7:686692.
Ogg, A. G. Jr. and Isakson, P. J. 2001. Agronomic benefits and concerns for Roundup-Ready® wheat. Proc. West. Soc Weed Sci 54:8090.
Ott, P. M., Dawson, J. H., and Appleby, A. P. 1989. Volunteer wheat (Triticum aestivum) in newly seeded alfalfa (Medicago sativa L). Weed Technol 3:375380.
Pickett, A. A. 1993. Cereals: seed shedding, dormancy, and longevity. Asp. Appl. Biol 35:1728.
Rainbolt, C. R., Thill, D. C., and Young, F. L. 2004. Control of volunteer herbicide-resistant wheat and canola. Weed Technol 18:711718.
Saskatchewan Soil Conservation Association. 2001. Roundup-Ready Wheat Position Paper. Saskatchewan Soil Conservation Association Online:
Staniforth, D. W. and Wiese, A. F. 1985. Weed biology and its relationship to weed control in limited-tillage systems. Pages 1525 in Wiese, A. F. ed. Weed Control in Limited-Tillage Systems. No. 2., Champaign, IL: Weed Science Society of America.
Thomas, A. G. and Leeson, J. Y. 1999. Persistence of volunteer wheat and canola using weed survey data. Sainte-Anne-de-Bellevue, Canada: Proc. 1999 Ann. Mtg. Expert Comm. Weeds, P. 88.
Van Acker, R. C., Brule-Babel, A. L., and Friesen, L. F. 2004. Interspecific gene movement can create environmental risk: the example of Roundup Ready® wheat in western Canada. Pages 3747 in Breckling, B. and Verhoeven, R. eds. Risk Hazard Damage—Specification of Criteria to Assess Environmental Impact of Genetically Modified Organisms. Bonn: Bundesamt für Naturschutz—Naturschutz und Biologische Vielfalt.
Wicks, G. A. and Smika, D. E. 1990. Central Great Plains. Pages 127157 in Donald, W. ed. Systems of Weed Control in Wheat in North America. Champaign, IL: Weed Sci Soc. Am.
Wicks, G. A., Nordquist, P. T., Hanson, G. E., and Schmidt, J. W. 1994. Influence of winter wheat (Triticum aestivum) cultivars on weed control in sorghum (Sorghum bicolour). Weed Sci 42:2734.
Wicks, G. A., Popken, D. P., and Lowry, S. R. 1989. Survey of winter wheat (Triticum aestivum) stubble fields sprayed with herbicides after harvest in 1986. Weed Technol 3:244254.
Zhou, H., Berg, J. D., and Blank, S. E. et al. 2003. Field efficacy assessment of transgenic Roundup Ready wheat. Crop Sci 43:10721075.


Related content

Powered by UNSILO

Glyphosate-resistant wheat persistence in western Canadian cropping systems

  • K. Neil Harker, George W. Clayton (a1), Robert E. Blackshaw (a2), John T. O'Donovan (a3), Eric N. Johnson (a4), Yantai Gan (a5), Frederick A. Holm (a6), Ken L. Sapsford (a6), R. Byron Irvine (a7) and Rene C. Van Acker (a8)...


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.