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Timing and Dose of Metolachlor Affect Rigid Ryegrass (Lolium rigidum) Control in Wheat

Published online by Cambridge University Press:  20 January 2017

Bhagirath S. Chauhan*
Affiliation:
Discipline of Agricultural and Animal Science, The University of Adelaide, Roseworthy Campus, South Australia 5371
Gurjeet S. Gill
Affiliation:
Discipline of Agricultural and Animal Science, The University of Adelaide, Roseworthy Campus, South Australia 5371
Christopher Preston
Affiliation:
Discipline of Plant and Food Science, The University of Adelaide, Waite Campus, South Australia 5064
*
Corresponding author's E-mail: b.chauhan2@cgiar.org

Abstract

The efficacy of metolachlor on rigid ryegrass was determined under a no-till seeding system in an experiment conducted in 2004 and 2005 in South Australia. Metolachlor at a rate of 0.48 and 0.96 kg ai/ha was applied at 40 or 46 d (very early preplant, VEPP) and 20 or 23 d before crop sowing (early preplant, EPP), and at sowing (preplant, PP) in 2004 and 2005; the herbicide was incorporated by sowing. The control of rigid ryegrass was greater than 80% when metolachlor was applied PP; however, that application resulted in phytotoxic effects on emergence and yield of wheat; metolachlor was more phytotoxic when applied at 0.96 kg/ha than at 0.48 kg/ha. Metolachlor applied EPP provided 71 to 83% rigid ryegrass control, whereas VEPP application provided only 33 to 49% control. Reduction in wheat grain yield was not observed at these application times. This study indicates that metolachlor at 0.48 kg/ha could be safely applied around 20 d before crop sowing to selectively control rigid ryegrass in wheat.

Type
Research
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Accinelli, C., Dinelli, G., and Vicari, A. 2001. Atrazine and metolachlor degradation in subsoils. Biol. Fert. Soils 33:495500.Google Scholar
Ahrens, W. H. 1994. Herbicide Handbook. 7th ed. Champaign, IL Weed Science Society of America. 197220.Google Scholar
Beestman, G. B. and Deming, J. M. 1974. Dissipation of acetanilide herbicides from soils. Agron. J. 66:308311.Google Scholar
Llewellyn, R. S. and Powles, S. B. 2001. High levels of herbicide resistance in rigid ryegrass (Lolium rigidum) in the wheat belt of Western Australia. Weed Technol. 15:242248.Google Scholar
McAlister, F. M., Holtum, J. A. M., and Powles, S. B. 1995. Dinitroaniline herbicide resistance in rigid ryegrass (Lolium rigidum). Weed Sci. 43:5562.Google Scholar
Mueller, T. C., Shaw, D. R., and Witt, W. W. 1999. Relative dissipation of acetochlor, alachlor, metolachlor, and SAN 582 from three surface soils. Weed Technol. 13:341346.Google Scholar
Ritter, R. L. and Menbere, H. 2002. Preemergence control of Italian ryegrass (Lolium multiflorum) in wheat (Triticum aestivum). Weed Technol. 16:5559.CrossRefGoogle Scholar
Rouchaud, J., Neus, O., Cools, K., and Bulcke, R. 1999. Flufenacet soil persistence and mobility in corn and wheat crops. Bull. Environ. Contam. Toxicol. 63:460466.Google Scholar
Walsh, M. J., Devlin, R. D., and Powles, S. B. 2004. Potential for preseason herbicide application to prevent weed emergence in the subsequent growing season. 1. Identification and evaluation of possible herbicides. Weed Technol. 18:228235.Google Scholar
Zimdahl, R. L. and Clark, S. K. 1982. Degradation of three acetanilide herbicides in soil. Weed Sci. 30:545548.Google Scholar