The Incidence and Ramifications of Glyphosate Resistance in Cotton. (1st February 2016)

• Record Type: Journal Article
• Authors: Norsworthy, Jason; Schwartz, Lauren; Barber, L. Tom
• Is Part Of: Outlooks on pest management. Volume 27:Number 1(2016:Jan./Feb.)
• Page Start: 31
• Page End: 35
• Publication Date: 2016-02-01
• Subjects: Pesticides -- Periodicals; Pesticides -- Application -- Periodicals; 632.905
• DOI: 10.1564/v27_feb_07
• Languages: English
• ISSNs: 1743-1034

Abstract

Herbicide-resistant cotton (Gossypium hirsutum) comprises one of the largest genetically modified crops within the United States (U.S.) along with corn (Zea mays) and soybean (Glycine max) (Figure 1). These genetically engineered (GE) crop hectares consisted primarily of the glyphosate-resistant trait shortly after commercialization of this technology in soybean, cotton, and corn in 1996, 1997, and 1998, respectively. Simplicity and increased grower revenues were prominent reasons cited for rapid adoption of glyphosate-resistant (GR) crops across vast areas. Ultimately, the overuse of glyphosate in Roundup Ready (RR) cotton in the U.S. quickly led to shifts in the weed spectrum and an increasing occurrence of GR weeds (Reddy & Norsworthy 2010; Riar et al., 2013). In 2012, it was estimated that more than 24.7 million ha had been affected by GR weeds (Owen et al., 2015) and that number has most likely increased. It has well been established that repeated use of any single management tactic, including cultural or nonchemical, across vast hectares will quickly select for resistance; hence, the occurrence of GR weeds across much of the U.S. Cotton Belt came as no surprise considering that RR cotton was planted on almost every cotton hectare, especially in the Midsouth and Southeast in early 2000s (Norsworthy et al., 2006; Nichols et al., 2009).