Skip to main content
    • Aa
    • Aa

Weed Control and Crop Response to Glufosinate Applied to ‘PHY 485 WRF’ Cotton

  • A. Stanley Culpepper (a1), Alan C. York (a2), Phillip Roberts (a3) and Jared R. Whitaker (a2)

Field experiments were conducted in Georgia to evaluate weed control and crop tolerance with glufosinate applied to ‘PHY 485 WRF®’ cotton. This glyphosate-resistant cotton also contains a gene, used as a selectable marker, for glufosinate resistance. Three experiments were maintained weed-free and focused on crop tolerance; a fourth experiment focused on control of pitted morningglory and glyphosate-resistant Palmer amaranth. In two experiments, PHY 485 WRF cotton was visibly injured 15 and 20% or less by glufosinate ammonium salt at 430 and 860 g ae/ha, respectively, applied POST two or three times. In a third experiment, glufosinate at 550 g/ha injured cotton up to 36%. Pyrithiobac or glyphosate mixed with glufosinate did not increase injury compared to glufosinate applied alone; S-metolachlor mixed with glufosinate increased injury by six to seven percentage points. Cotton injury was not detectable 14 to 21 d after glufosinate application, and cotton yields were not reduced by glufosinate or glufosinate mixtures. A program of pendimethalin PRE, glyphosate applied POST twice, and diuron plus MSMA POST-directed controlled glyphosate-resistant Palmer amaranth only 17% late in the season. S-metolachlor included with the initial glyphosate application did not increase control, and pyrithiobac increased late-season control by only 13 percentage points. Palmer amaranth was controlled 90% or more when glufosinate replaced glyphosate in the aforementioned system. Pitted morningglory was controlled 99% by all glufosinate programs and mixtures of glyphosate plus pyrithiobac. Seed cotton yields with glufosinate-based systems were at least 3.3 times greater than yields with glyphosate-based systems because of differences in control of glyphosate-resistant Palmer amaranth.

Corresponding author
Corresponding author's E-mail:
Linked references
Hide All

This list contains references from the content that can be linked to their source. For a full set of references and notes please see the PDF or HTML where available.

S. D. Askew , W. A. Bailey , G. H. Scott , and J. W. Wilcut 2002. Economic assessment of weed management in transgenic and nontransgenic cotton in tilled and nontilled systems. Weed Sci 50:512520.

M. R. Behrens , N. Mutlu , S. Chakraborty , R. Dumitru , W. Z. Jiang , B. J. LaValle , P. L. Herman , T. E. Clemente , and D. P. Weeks 2007. Dicamba resistance: enlarging and preserving biotechnology-based weed management strategies. Science 316:11851188.

L. K. Blair-Kerth , P. A. Dotray , J. R. Gannaway , M. J. Oliver , and J. E. Quisenberry 2001. Tolerance of transformed cotton to glufosinate. Weed Sci 49:375380.

Coetzer , E. K. Al-Khatib , and D. E. Peterson 2002. Glufosinate efficacy on Amaranthus species in glufosinate-resistant soybean (Glycine max). Weed Technol 16:326331.

A. S. Culpepper , A. C. York , R. B. Batts , and K. M. Jennings 2000. Weed management in glufosinate- and glyphosate-resistant soybean (Glycine max). Weed Technol 14:7788.

W. J. Grichar , B. A. Besler , K. D. Brewer , and B. W. Minton 2004. Using soil-applied herbicides in combination with glyphosate in a glyphosate-resistant cotton herbicide program. Crop Protect 23/10:10071010.

M. J. Horak and T. M. Loughin 2000. Growth analysis of four Amaranthus species. Weed Sci 48:347355.

C. H. Koger , I. C. Burke , D. K. Miller , J. A. Kendig , K. N. Reddy , and J. W. Wilcut 2007. MSMA antagonizes glyphosate and glufosinate efficacy on broadleaf and grass weeds. Weed Technol 21:159165.

H. Mullner , P. Eckes , and G. Donn 1993. Engineering crop resistance to the naturally occurring glutamine synthetase inhibitor phosphinothricin. Pages 3847. In S. O. Duke , J. J. Menn , and J. R. Plimmer Pest Control with Enhanced Environmental Safety. Washington, DC: American Chemical Society Series 524.

T. J. Muzik and W. G. Mauldin 1964. Influence of environment on the response of plants to herbicides. Weeds 12:142145.

J. L. Norris , D. R. Shaw , and C. E. Snipes 2002. Influence of row spacing and residual herbicides on weed control in glufosinate-resistant soybean (Glycine max). Weed Technol 16:319325.

J. K. Norsworthy , G. M. Griffith , R. C. Scott , K. L. Smith , and L. R. Oliver 2008. Confirmation and control of glyphosate-resistant Palmer amaranth (Amaranthus palmeri) in Arkansas. Weed Technol 22:108113.

C. M. Whaley , H. P. Wilson , and J. H. Westwood 2007. A new mutation in plant Als confers resistance to five classes of ALS-inhibiting herbicides. Weed Sci 55:8390.

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Weed Technology
  • ISSN: 0890-037X
  • EISSN: 1550-2740
  • URL: /core/journals/weed-technology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Full text views

Total number of HTML views: 0
Total number of PDF views: 4 *
Loading metrics...

Abstract views

Total abstract views: 32 *
Loading metrics...

* Views captured on Cambridge Core between 20th January 2017 - 27th June 2017. This data will be updated every 24 hours.