EPSPS amplification in glyphosate-resistant spiny amaranth (Amaranthus spinosus): a case of gene transfer via interspecific hybridization from glyphosate-resistant Palmer amaranth (Amaranthus palmeri)
Article first published online: 20 MAR 2014
Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Pest Management Science
Volume 70, Issue 12, pages 1902–1909, December 2014
How to Cite
Nandula, V. K., Wright, A. A., Bond, J. A., Ray, J. D., Eubank, T. W. and Molin, W. T. (2014), EPSPS amplification in glyphosate-resistant spiny amaranth (Amaranthus spinosus): a case of gene transfer via interspecific hybridization from glyphosate-resistant Palmer amaranth (Amaranthus palmeri). Pest. Manag. Sci., 70: 1902–1909. doi: 10.1002/ps.3754
- Issue published online: 3 NOV 2014
- Article first published online: 20 MAR 2014
- Accepted manuscript online: 4 FEB 2014 11:36AM EST
- Manuscript Accepted: 27 JAN 2014
- Manuscript Revised: 24 DEC 2013
- Manuscript Received: 6 SEP 2013
- Amaranthus spinosus;
- gene amplification;
- gene transfer;
- herbicide resistance;
- interspecific hybridization;
Amaranthus spinosus, a common weed of pastures, is a close relative of Amaranthus palmeri, a problematic agricultural weed with widespread glyphosate resistance. These two species have been known to hybridize, allowing for transfer of glyphosate resistance. Glyphosate-resistant A. spinosus was recently suspected in a cotton field in Mississippi.
Glyphosate-resistant A. spinosus biotypes exhibited a fivefold increase in resistance compared with a glyphosate-susceptible biotype. EPSPS was amplified 33–37 times and expressed 37 times more in glyphosate-resistant A. spinosus biotypes than in a susceptible biotype. The EPSPS sequence in resistant A. spinosus plants was identical to the EPSPS in glyphosate-resistant A. palmeri, but differed at 29 nucleotides from the EPSPS in susceptible A. spinosus plants. PCR analysis revealed similarities between the glyphosate-resistant A. palmeri amplicon and glyphosate-resistant A. spinosus.
Glyphosate resistance in A. spinosus is caused by amplification of the EPSPS gene. Evidence suggests that part of the EPSPS amplicon from resistant A. palmeri is present in glyphosate-resistant A. spinosus. This is likely due to a hybridization event between A. spinosus and glyphosate-resistant A. palmeri somewhere in the lineage of the glyphosate-resistant A. spinosus plants. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.