No fitness cost of glyphosate resistance endowed by massive EPSPS gene amplification in Amaranthus palmeri

Authors
Vila Aiub, Martin Miguel; Goh, Sou S.; Gaines, Todd A.; Han, Heping; Busi, Roberto; Yu, Qin; Powles, Stephen B.
Publication Year
2014
Language
English
Format
article
Status
Published version
Description
Amplification of the EPSPS gene has been previously identified as the glyphosate resistance mechanism in many populations of Amaranthus palmeri, a major weed pest in U.S. agriculture. Here, we evaluate the effects of EPSPS gene amplification on both the level of glyphosate resistance and fitness cost of resistance. Amaranthus palmeri individuals resistant to glyphosate by expressing a wide range of EPSPS gene copy numbers were evaluated under competitive conditions in the presence or absence of glyphosate. Survival rates to glyphosate and fitness traits of plants under intra-specific competition were assessed. Plants with higher amplification of the EPSPS gene (53-fold) showed high levels of glyphosate resistance, whereas less amplification of the EPSPS gene (21-fold) endowed a lower level of glyphosate resistance. Without glyphosate but under competitive conditions, plants exhibiting up to 76-fold EPSPS gene amplification exhibited similar height, and biomass allocation to vegetative and reproductive organs, compared to glyphosate susceptible A. palmeri plants with no amplification of the EPSPS gene. Both the additive effects of EPSPS gene amplification on the level of glyphosate resistance and the lack of associated fitness costs are key factors contributing to EPSPS gene amplification as a widespread and important glyphosate resistance mechanism likely to become much more evident in weed plant species.
Fil: Vila Aiub, Martin Miguel. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina
Fil: Goh, Sou S.. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia
Fil: Gaines, Todd A.. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia
Fil: Han, Heping. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia
Fil: Busi, Roberto. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia
Fil: Yu, Qin. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia
Fil: Powles, Stephen B.. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia
Subject
Evolution
Fitness Traits
Gene Over-expression
Herbicide Resistance
Ecología
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/4225