A novel EPSPS Pro-106-His mutation confers the first case of glyphosate resistance in Digitaria sanguinalis.

Autor: Yanniccari M; Chacra Experimental Integrada Barrow (MDA-INTA), National Scientific and Technical Research Council (CONICET), Faculty of Agronomy, National University of La Pampa, La Pampa, Argentina., Vázquez-García JG; Department of Agroforestry, Plant Biochemistry and Molecular Biology, University of Cordoba, Cordoba, Spain., Gigón R; Private Consultant in Weed Control, Tres Arroyos, Argentina., Palma-Bautista C; Department of Agroforestry, Plant Biochemistry and Molecular Biology, University of Cordoba, Cordoba, Spain., Vila-Aiub M; Department of Ecology, IFEVA-CONICET, Faculty of Agronomy, University of Buenos Aires (UBA), Buenos Aires, Argentina., De Prado R; Department of Agroforestry, Plant Biochemistry and Molecular Biology, University of Cordoba, Cordoba, Spain.
Jazyk: angličtina
Zdroj: Pest management science [Pest Manag Sci] 2022 Jul; Vol. 78 (7), pp. 3135-3143. Date of Electronic Publication: 2022 May 09.
DOI: 10.1002/ps.6940
Abstrakt: Background: Digitaria sanguinalis has been identified as a species at high risk of evolving herbicide resistance, but thus far, there are no records of resistance to glyphosate. This weed is one of the most common weeds of summer crops in extensive cropping areas in Argentina. It shows an extended period of seedling emergence with several overlapping cohorts during spring and summer, and is commonly controlled with glyphosate. However, a D. sanguinalis population was implicated as a putative glyphosate-resistant biotype based on poor control at recommended glyphosate doses.
Results: The field-collected D. sanguinalis population (Dgs R) from the Rolling Pampas has evolved glyphosate resistance. Differences in plant survival and shikimate levels after field-recommended and higher glyphosate doses were evident between Dgs R and the known susceptible (Dgs S) population; the resistance index was 5.1. No evidence of differential glyphosate absorption, translocation, metabolism or basal EPSPS activity was found between Dgs S and Dgs R populations; however, a novel EPSPS Pro-106-His point substitution is probably the primary glyphosate resistance-endowing mechanism. EPSPS in vitro enzymatic activity demonstrated that an 80-fold higher concentration of glyphosate is required in Dgs R to achieve similar EPSPS activity inhibition to that in the Dgs S population.
Conclusion: This study reports the first global case of glyphosate resistance in D. sanguinalis. This unlikely yet novel transversion at the second position of the EPSPS 106 codon demonstrates the intensity of glyphosate pressure in selecting unexpected glyphosate resistance alleles if they retain EPSPS functionality. © 2022 Society of Chemical Industry.
(© 2022 Society of Chemical Industry.)
Databáze: MEDLINE
Externí odkaz: