Hostname: page-component-77c89778f8-vsgnj Total loading time: 0 Render date: 2024-07-17T21:42:02.992Z Has data issue: false hasContentIssue false

Differences in Glyphosate-Resistant Weed Management Practices over Time and Regions

Published online by Cambridge University Press:  20 January 2017

Xia “Vivian” Zhou*
Department of Agricultural and Resource Economics, University of Tennessee, Knoxville, TN 37996
Roland K. Roberts
Department of Agricultural and Resource Economics, University of Tennessee, Knoxville, TN 37996
James A. Larson
Department of Agricultural and Resource Economics, University of Tennessee, Knoxville, TN 37996
Dayton M. Lambert
Department of Agricultural and Resource Economics, University of Tennessee, Knoxville, TN 37996
Burton C. English
Department of Agricultural and Resource Economics, University of Tennessee, Knoxville, TN 37996
Ashok K. Mishra
Department of Agricultural Economics and Agribusiness, Louisiana State University, Baton Rouge, LA 70803
Lawrence L. Falconer
Delta Research and Extension Center, Mississippi State University, Stoneville, MS 38776
Robert J. Hogan Jr.
Department of Agricultural Economics, Texas A&M University, Stephenville, TX 76401
Jason L. Johnson
Department of Agricultural Economics, Texas A&M University, Stephenville, TX 76401
Jeanne M. Reeves
Agricultural and Environmental Research, Cotton Incorporated, Cary, NC 27513
Corresponding author's E-mail:


The objective of this research was to describe proportional differences across time and region in management practices among southern cotton farmers who experienced glyphosate-resistant (GR) weeds on their farms earlier than those who experienced them later and among farmers who were closest to one of four historical outbreak epicenters: Lauderdale County, TN; Macon County, GA; Edgecombe County, NC; and Terry County, TX. A mail survey was conducted with cotton farmers in 2012 from 13 southern, cotton-producing states. Survey responses on practices used by farmers were classified into three broad categories of labor, mechanical/tillage/chemical (MTC), and cultural. Proportions of respondents using practices from each category were identified by time and region; across which, proportional-difference tests were conducted. Results indicated respondents encountering GR weeds earlier were more likely than farmers who experienced them later to use the three broad-category practices (labor, 98 vs. 92%; MTC, 95 vs. 89%; and cultural, 86 vs. 76%) and specific practices, including hooded sprayers (76 vs. 58%), in-season herbicide change (83 vs. 60%), and field-border management (60 vs. 35%). Also, respondents closest to Lauderdale County were more likely than farmers closest to Edgecombe County to use broad-labor practices (99 vs. 91%) and specific practices, including hand hoeing (96 vs. 84%), hand spraying (49 vs. 31%), spot spraying (76 vs. 59%), wick applicator (13 vs. 11%), and field-border management (58 vs. 39%). Education programs on weed management can be developed and tailored according to the time and regional differences to provide effective information and communication channels to farmers.

El objetivo de esta investigación fue describir las diferencias proporcionales entre productores sureños de algodón en el uso de prácticas culturales, considerando el momento y la región, para productores que han tenido malezas resistentes a glyphosate (GR) en sus fincas primero y productores que las han tenido después, y entre productores que estuvieron cerca de uno de cuatro epicentros históricos de aparición de resistencia: condado Lauderdale, Tennessee; condado Macon, Georgia; condado Edgecombe, North Carolina; y condado Terry, Texas. Se realizó una encuesta por correo con productores de algodón en 2012 en 13 estados sureños productores de algodón. Las respuestas de la encuesta sobre las prácticas usadas por los productores fueron clasificadas en tres amplias categorías: mano de obra, mecánicas/labranza/químicas (MTC), y culturales. Las proporciones de los que respondieron que usaron prácticas de cada categoría fueron identificadas por momento y región; entre las cuales se realizaron pruebas de diferencias entre proporciones. Los resultados indicaron que quienes respondieron y encontraron malezas GR temprano, tuvieron más probabilidad de usar las tres categorías de prácticas que aquellos que encontraron malezas GR después (labranza, 98 vs. 92%, MTC, 95 vs. 89%, y cultural, 86 vs. 76%) y prácticas específicas que incluyeron aspersores con coberturas de campana (76 s. 58%), cambio de herbicidas durante la temporada de producción (83 vs. 60%), y el manejo de malezas en los bordes de los campos (60 vs. 35%). Además, los encuestados más cercanos al condado Lauderdale fueron los que tuvieron una mayor probabilidad de usar prácticas con mano de obra (99 vs. 91%) que los productores cercanos al condado Edgecombe, y prácticas que incluyeron labranza manual con azadón (96 vs. 84%), aplicación de herbicidas manual (49 vs. 31%), aplicaciones dirigidas (76 vs. 59%), aplicador con azadón químico (13 vs. 11%), y manejo de malezas en los bordes del terreno (58 vs. 39%). Los programas de educación en el manejo de malezas pueden ser desarrollados y dirigidos dependiendo de las diferencias en los momentos y las regiones en que se detecta la resistencia para brindar información y canales de comunicación efectivos para los productores.

Research Article
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.)


Associate Editor for this paper: Lawrence E. Steckel, University of Tennessee.


Literature Cited

Anonymous (2002) Managing Glyphosate-Resistant Weeds—An Investment in Land Value. Syngenta Crop Protection. Accessed October 31, 2005Google Scholar
Baldwin, F (2011) Going Back in Time for Weed Control. Delta Farm Press. Accessed May 22, 2014Google Scholar
Beckie, HJ (2006) Herbicide-resistant weeds: management tactics and practices. Weed Technol 20:793814 Google Scholar
Bonny, S (2008) Genetically modified glyphosate-tolerant soybean in the USA: adoption factors, impacts and prospects—a review. Agron Sustain Dev 28:2132 Google Scholar
Brandon, H (2011) Herbicide resistant weeds cost farmers millions. Delta Farm Press Blog February 25. Accessed November 5, 2015Google Scholar
Cline, H. (2013). Palmer Amaranth Resistance Spreads in Texas High Plains. Southeast Farm Press. Accessed: January 10, 2013Google Scholar
Culpepper, AS (2006) Glyphosate-induced weed shifts. Weed Technol 20:277281 Google Scholar
Culpepper, AS, York, AC, Kichler, J (2008) University of Georgia herbicide programs for controlling glyphosate-resistant Palmer amaranth in 2008 cotton. Tifton, GA: Georgia Cooperative Extension Service Circular 924Google Scholar
Dillman, DA (1978) Mail and Telephone Surveys: The Total Design Method. New York: Wiley & Sons. 325 Google Scholar
Duke, SO, Powles, SB (2008) Mini-review glyphosate: a once-in-a-century herbicide. Pest Manag Sci 64:319325 Google Scholar
Duzy, LM, Price, AJ, Balkcom, KS (2011) Estimating the net returns of managing pigweed in cotton. Pages 336339 in Proceedings of Beltwide Cotton Conference. Cordova, TN National Cotton Council of America Google Scholar
Foresman, C, Glasgow, L (2008) US grower perceptions and experiences with glyphosate-resistant weeds. Pest Manag Sci 64:388391 Google Scholar
Franz, JE, Mao, MK, Sikorski, JA (1996) Glyphosate: a unique global pesticide. Washington, DC: American Chemical Society. 653 pGoogle Scholar
Frisvold, GB, Hurley, TM, Mitchell, PD (2009) Adoption of best management practices to control weed resistance by corn, cotton, and soybean growers. Agbioforum 12:370381 Google Scholar
Givens, WA, Shaw, DR, Newman, ME, Weller, SC, Young, BG, Wilson, RG, Owene, MDK, Jorda, DL (2011) Benchmark study on glyphosate-resistant cropping systems in the United States, part 3: grower awareness, information sources, experiences and management practices regarding glyphosate-resistant weeds. Pest Manag Sci 67:758770 Google Scholar
Green, JM (2007) Review of glyphosate and ALS-inhibiting herbicide crop resistance and resistant weed management. Weed Technol 21:547558 Google Scholar
Green, JM (2012) The benefits of herbicide-resistant crops. Pest Manag Sci 68:13231331 Google Scholar
Harrington, J, Byrne, PF, Peairs, FB, Nissen, SJ, Westra, P, Ellsworth, PC, Fournier, AL, Mallory-Smith, CA, Zemetra, RS, Henry, WB (2009) Perceived consequences of herbicide-tolerant and insect-resistant crops on integrated pest management strategies in the western United States: results of an online survey. Agbioforum 12:412421 Google Scholar
Hayes, RM, Mueller, TC, Willis, JB, Montgomery, RF (2002) Glyphosate-resistant horseweed and factors influencing its control. Proc South Weed Sci Soc 55:119120 Google Scholar
Heap, I (2008) International Survey of Herbicide Resistant Weeds. Weed Science Society of America. Accessed June 21, 2014Google Scholar
Holm, LG, Plunknett, DL, Pancho, JV, Herberger, JP (1977) The World's Worst Weeds: Distribution and Biology. Honolulu, HI: University Press of Hawaii. 609 pGoogle Scholar
Johnson, WG, Davis, VM, Kruger, GR, Weller, SC (2009a) Influence of glyphosate-resistant cropping systems on weed species shifts and glyphosate-resistant weed populations. Eur J Agron 31:162172 Google Scholar
Johnson WG Gibson KD (2006) Glyphosate-resistant weeds and resistance management strategies: an Indiana grower perspective. Weed Technol 20:768772 Google Scholar
Johnson, WG, Owen, MDK, Kruger, GR, Young, BG, Shaw, DR, Wilson, RG, Wilcut, JW, Jordan, DL, Weller, SC, Bernards, ML, Young, BG (2009b) U.S. farmer awareness of glyphosate-resistant weeds and resistance management strategies. Weed Technol 23:308312 Google Scholar
Kruger, GR, Johnson, WG, Weller, SC, Owen, MDK, Shaw, DR, Wilcut, JW, Jordan, DL, Wilson, RG, Bernards, ML, Young, BG (2009) US grower views on problematic weeds and changes in weed pressure in glyphosate-resistant corn, cotton, and soybean cropping systems. Weed Technol 23:162166 Google Scholar
Laws, F (2010) Cotton: 2 Strikes in Weed Resistance. Southeast Farm Press. Accessed August 20, 2014Google Scholar
Llewellyn, RS, Lindner, RK, Pannell, DJ, Powles, SB (2002) Resistance and the herbicide resource: perceptions of Western Australian grain growers. Crop Prot 21: 10671075 Google Scholar
Lohr, SL (1999) Sampling: Design and Analysis. Pacific Grove, CA: Duxbury Pp 3942 Google Scholar
Norsworthy, JK, Griffith, GM, Scott, RC, Smith, KL, Oliver, LR (2008) Confirmation and control of glyphosate-resistant Palmer amaranth (Amaranthus palmeri) in Arkansas. Weed Technol 22:108113 Google Scholar
Norsworthy, JK, Ward, SM, Shaw, DR, Llewellyn, RS, Nichols, RL, Webster, TM, Bradley, KW, Frisvold, G, Powles, SB, Burgos, NR, Witt, WW, Barrett, M (2012) Reducing the risks of herbicide resistance: best management practices and recommendations. Weed Sci 60:3162 Google Scholar
Owen, MDK, Zelaya, IA (2005) Herbicide-resistant crops and weed resistance to herbicides. Pest Manag Sci 61:301311 Google Scholar
Prince, JM, Shaw, DR, Givens, WA, Newman, ME, Owen, MDK, Weller, SC, Young, BG, Wilson, RG, Jordan, DL (2012) Benchmark study, II: a 2010 survey to assess grower awareness of and attitudes toward glyphosate resistance. Weed Technol 26:531535 Google Scholar
Roberson, R (2011) Glyphosate resistant pigweed arrives in Virginia. Southeast Farm Press. Accessed December 5, 2013Google Scholar
Roberts, RK, English, BC, Gao, Q, Larson, JA (2006) Simultaneous adoption of herbicide-resistant and conservation-tillage cotton technologies. J Agric Appl Econ 38:629643 Google Scholar
Robinson, E (2010) Old technology coming out of the closet. Delta Farm Press Accessed October 12, 2014Google Scholar
Rowland, MW, Murray, DS, Verhalen, LM (1999) Full-season Palmer amaranth (Amaranthus palmeri) interference with cotton (Gossypium hirsutum). Weed Sci 47:305309 Google Scholar
Scott, BA, VanGessel, MJ (2007) Delaware soybean grower survey on glyphosate-resistant horseweed (Conyza canadensis). Weed Technol 21:270274 Google Scholar
Sheskin, D (2011) Test 29: Spearman's rank-order correlation coefficient. Page 1353 in Sheskin, DJ, ed., Handbook of Parametric and Nonparametric Statistical Procedures, 5th edn. Boca Raton, FL: Chapman & Hall/CRC Google Scholar
Snedecor, GW, Cochran, WG (1967) Statistical Methods. 6th edn. Ames, IA: Iowa State University Press. 593 Google Scholar
StataCorp (2013) Stata Statistical Software: Release 13, College Station, TX: StataCorp Google Scholar
Steckel, L (2006) Horseweed. Knoxville, TN: University of Tennessee Extension Fact Sheet 06-0034Google Scholar
Tillé, Y (1996) An elimination procedure for unequal probability sampling without replacement. Biometrika 83:238241 Google Scholar
[USDA-NASS] United States Department of Agriculture-National Agricultural Statistics Service (2011) CropScape and Cropland Data Layer. Washington, DC: Department of Agriculture Google Scholar
VanGessel, MJ (2001) Glyphosate resistant horseweed from Delaware. Weed Sci 49:703705 Google Scholar
Yancy, CH (2003) Glyphosate resistant horseweed causing concern in North Carolina. Southeast Farm Press. Accessed November 17, 2014Google Scholar
Zhou, X, Larson, J A, Lambert, DM, Roberts, RK, English, BC, Bryant, KJ, Mishra, AK, Falconer, LL, Hogan, RJ, Johnson, JL, Reeves, JM (2015) Farmer experience with weed resistance to herbicide in cotton production. Agbioforum 18:112 Google Scholar