Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-24T07:53:04.802Z Has data issue: false hasContentIssue false

Defining Optimum Herbicide Rates and Timing for Wild Oat (Avena fatua) Control in Spring Wheat (Triticum aestivum)

Published online by Cambridge University Press:  20 January 2017

F. A. Holm*
Affiliation:
Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, Canada S7N 5A8
Ken J. Kirkland
Affiliation:
Agriculture and Agri-Food Canada Research Farm, Box 10, Scott, SK, Canada S0K 4A0
F. Craig Stevenson
Affiliation:
206A Dunlop Street, Saskatoon, SK, Canada S7N 2B7
*
Corresponding author's E-mail: [email protected].

Abstract

Knowledge of optimal combinations of graminicide rate and stage of application could improve the effectiveness and net benefit of commonly used graminicides. A study was conducted at two locations in Saskatchewan, Canada, from 1994 to 1997. Factorial combinations of five graminicides (CGA 184927, fenoxaprop-p-ethyl, ICIA 0604, imazamethabenz, and flamprop-methyl), three graminicide rates (full, two-thirds, and one-third recommended label rate), and three leaf stages of wild oat (Avena fatua; two-, four-, and six-leaf) were compared to determine their effect on wild oat fresh weight, wheat (Triticum aestivum) seed yield, and net return. Wild oat fresh weight increased and wheat seed yield decreased to a greater extent at Saskatoon (median wild oat fresh weight of 56 g/m2) than at Scott (median wild oat fresh weight of 85 g/m2) when graminicide rate was reduced from the recommended label rate. Net return consistently decreased at both locations and among all graminicides when application rate was reduced from two-thirds to one-third of the recommended label rate. Imazamethabenz applied at progressively later growth stages caused greater wild oat fresh weight at both locations and reduced wheat yield and net return. Applying other graminicides at the earliest (two-leaf) stage of wild oat generally resulted in more or similar levels of wild oat fresh weight compared with delayed applications, especially at Saskatoon. With the exception of imazamethabenz, crop yield and net return were unaffected by leaf stage at both locations. The optimal graminicide rate is mostly dependent on the level of wild oat infestation, and the best time to control wild oat is dependent mostly on the particular graminicide.

Type
Research
Copyright
Copyright © Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

Barton, D. L., Thill, D. C., and Shafii, B. 1992. Integrated wild oat (Avena fatua) management affects spring barley (Hordeum vulgare) yield and economics. Weed Technol. 6: 129135.Google Scholar
Crop Protection Guide. 1997. Chemical Weed Control. Regina, SK: Saskatchewan Agriculture and Food Publication 207 p.Google Scholar
Harker, K. N. and Blackshaw, R. E. 1991. Influence of growth stage and broadleaf herbicides on tralkoxydim activity. Weed Sci. 39: 650659.Google Scholar
Harker, K. N. and O'Sullivan, P. A. 1991. Effect of imazamethabenz on different growth stages of green foxtail, Tatary buckwheat and wild oat. Can. J. Plant Sci. 71: 821829.Google Scholar
Lemerle, D. and Verbeek, B. 1995. Influence of soil water deficit on performance of foliar-applied herbicides for wild oat and annual ryegrass in wheat. Plant Prot. Q. 10: 143147.Google Scholar
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.Google Scholar
Miller, S. D. and Alley, H. P. 1987. Weed control and rotational crop response with AC 222,293. Weed Technol. 1: 2933.Google Scholar
O'Donovan, J. T., de St. Remy, E. A., O'Sullivan, P. A., Dew, D. A., and Sharma, K. A. 1985. Influence of the relative time of emergence of wild oat (Avena fatua) on yield loss of barley (Hordeum vulgare) and wheat (Triticum aestivum). Weed Sci. 33: 498503.Google Scholar
Spandl, E., Durgan, B. R., and Miller, D. W. 1997. Wild oat (Avena fatua) control in spring wheat (Triticum aestivum) and barley (Hordeum vulgare) with reduced rates of postemergence herbicides. Weed Technol. 11: 591597.Google Scholar
Stougaard, R. N., Maxwell, B. D., and Harris, J. D. 1997. Influence of application timing on the efficacy of reduced rate postemergence herbicides for wild oat (Avena fatua) control in spring barley (Hordeum vulgare). Weed Technol. 11: 283289.Google Scholar
Tabachnick, B. G. and Fidell, L. S., eds. 1996. Principal components and factor analysis. In Using Multivariate Statistics. 3rd ed. New York: Harper Collins College Publishers. p. 82.Google Scholar