1. Effect of Ile-1781-Leu and Asp-2078-Gly ACCase gene mutations on ACCase kinetics and growth traits in Lolium rigidum
- Author
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Vila Aiub, Martin Miguel, Yu, Quin, Han, Heping, and Powles, Stephen B.
- Subjects
purl.org/becyt/ford/1 [https] ,RGR ,Ciencias Biológicas ,Competition ,Resistance cost ,Alopecurus myosuroides ,food and beverages ,ACCase activity ,Resistance mutation ,Ecología ,purl.org/becyt/ford/1.6 [https] ,CIENCIAS NATURALES Y EXACTAS - Abstract
The rate of herbicide resistance evolution in plants depends on fitness traits endowed by alleles in both the presence and absence (resistance cost) of herbicide selection. The effect of two Lolium rigidum spontaneous homozygous target-site resistance-endowing mutations (Ile-1781-Leu, Asp-2078-Gly) on both ACCase activity and various plant growth traits have been investigated here. Relative growth rate (RGR) and components (net assimilation rate, leaf area ratio), resource allocation to different organs, and growth responses in competition with a wheat crop were assessed. Unlike plants carrying the Ile-1781-Leu resistance mutation, plants homozygous for the Asp-2078-Gly mutation exhibited a significantly lower RGR (30%), which translated into lower allocation of biomass to roots, shoots, and leaves,and poor responses to plant competition. Both the negligible and significant growth reductions associated, respectively, with the Ile-1781-Leu and Asp-2078-Gly resistance mutations correlated with their impact on ACCase activity. Whereas the Ile-1781-Leu mutation showed no pleiotropic effects on ACCase kinetics, the Asp-2078-Gly mutation ledto a significant reduction in ACCase activity. The impaired growth traits are discussed in the context of resistance costs and the effects of each resistance allele on ACCase activity. Similar effects of these two particular ACCase mutations on the ACCase activity of Alopecurus myosuroides were also confirmed. Fil: Vila Aiub, Martin Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia Fil: Yu, Quin. 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: Powles, Stephen B.. University of Western Australia. School of Plant Biology. Australian Herbicide Resistance Initiative; Australia
- Published
- 2015