Publicação
Target-site and non-target-site resistance mechanisms confer multiple resistance to glyphosate and 2,4-D in Carduus acanthoides
| Resumo: | Carduus acanthoides L. is mainly a range-land weed, but in the 2010s has begun to invade GM crop production systems in C´ ordoba (Argentina), where glyphosate and 2,4-D have been commonly applied. In 2020, C. acanthoides was found with multiple resistance to these two herbicides. In this study, the mechanisms that confer multiple resistance to glyphosate and 2,4-D, were characterized in one resistant (R) population of C. acanthoides in comparison to a susceptible (S) population. No differences in 14C-herbicide absorption and translocation were observed between R and S populations. In addition, 14C-glyphosate was well translocated to the shoots (~30%) and roots (~16%) in both R and S plants, while most of 14C-2,4-D remained restricted in the treated leaf. Glyphosate metabolism did not contribute to resistance of the R population; however, as corroborated by malathion pretreatment, the mechanism of resistance to 2,4-D was enhanced metabolism (63% of the herbicide) mediated by cytochrome P450 (Cyt-P450). No differences were found in baseline EPSPS activity, copy number, and/or gene expression between the R and S populations, but a Pro-106-Ser mutation in EPSPS was present in the R population. Multiple resistances in the R population of C. acanthoides from Argentina were governed by target site resistance (a Pro-106 mutation for glyphosate) and non-target site resistance (Cyt-P450- based metabolic resistance for 2,4-D) mechanisms. This is the first case of resistance to glyphosate and 2,4-D confirmed for this weed in the world. |
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| Autores principais: | Palma-Bautista, Candelario |
| Outros Autores: | Belluccini, Pablo; Vázquez-Garcia, José G.; Alcántara-de la Cruz, Ricardo; Barro, Francisco; De Prado, Rafael; Fernandes, João |
| Assunto: | Auxinic herbicides Cytochrome P450 Herbicide metabolism Plumeless thistle Pro-106-Ser 5-enolpyruvylshikimate-3-phosphate synthase |
| Ano: | 2023 |
| País: | Portugal |
| Tipo de documento: | artigo |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Instituto Politécnico de Beja |
| Idioma: | inglês |
| Origem: | Repositório Institucional do IPBeja |
| Resumo: | Carduus acanthoides L. is mainly a range-land weed, but in the 2010s has begun to invade GM crop production systems in C´ ordoba (Argentina), where glyphosate and 2,4-D have been commonly applied. In 2020, C. acanthoides was found with multiple resistance to these two herbicides. In this study, the mechanisms that confer multiple resistance to glyphosate and 2,4-D, were characterized in one resistant (R) population of C. acanthoides in comparison to a susceptible (S) population. No differences in 14C-herbicide absorption and translocation were observed between R and S populations. In addition, 14C-glyphosate was well translocated to the shoots (~30%) and roots (~16%) in both R and S plants, while most of 14C-2,4-D remained restricted in the treated leaf. Glyphosate metabolism did not contribute to resistance of the R population; however, as corroborated by malathion pretreatment, the mechanism of resistance to 2,4-D was enhanced metabolism (63% of the herbicide) mediated by cytochrome P450 (Cyt-P450). No differences were found in baseline EPSPS activity, copy number, and/or gene expression between the R and S populations, but a Pro-106-Ser mutation in EPSPS was present in the R population. Multiple resistances in the R population of C. acanthoides from Argentina were governed by target site resistance (a Pro-106 mutation for glyphosate) and non-target site resistance (Cyt-P450- based metabolic resistance for 2,4-D) mechanisms. This is the first case of resistance to glyphosate and 2,4-D confirmed for this weed in the world. |
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