First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing
Kochia (Bassia scoparia (L.) A. J. Scott.) is a problematic weed. In Argentina, farmers have recently experienced poor control over imidazolinone-resistant sunflowers, specifically the sensitivity of putative kochia resistant plants to imidazolinone herbicides. Seeds from putative resistant populati...
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| Format: | Artículo |
| Language: | Inglés |
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Universidad de Concepción, Chile
2025
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| Online Access: | http://hdl.handle.net/20.500.12123/23761 https://revistas.udec.cl/index.php/chjaas/article/view/20256 https://doi.org/10.29393/CHJAAS41-33FRFA30033 |
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| author | Montoya, Jorgelina Ceferina Fabressi, Esteban E. Yanniccari, Marcos |
| author_browse | Fabressi, Esteban E. Montoya, Jorgelina Ceferina Yanniccari, Marcos |
| author_facet | Montoya, Jorgelina Ceferina Fabressi, Esteban E. Yanniccari, Marcos |
| author_sort | Montoya, Jorgelina Ceferina |
| collection | INTA Digital |
| description | Kochia (Bassia scoparia (L.) A. J. Scott.) is a problematic weed. In Argentina, farmers have recently experienced poor control over imidazolinone-resistant sunflowers, specifically the sensitivity of putative kochia resistant plants to imidazolinone herbicides. Seeds from putative resistant populations from Pellegrini (P), De Bary (DB), and 30 de Agosto (A) and a known susceptible (S) population from Col. Martín Fierro were sown in pots. A mixture of imazapyr (Clearsol® WG 80%) and imazamox (Trigosol WG 70%) was sprayed when plants reached approximately 6 cm in height and 10-leaf stage using a boom sprayer. A trial was conducted to determine the response of kochia to the recommended doses (1x) of imazapyr 80.00 g ai ha-1 + imazamox 20.30 g ai ha-1. Plants were harvested 30 days after treatment to determine fresh shoot weight. A dose–response experiment was performed using imazapyr + imazamox at concentrations of 0x, 1/4x, 1/2x, 1x, 2x, 4x, and 8x. Partial ALS gene amplification was performed using leaves of plants that survived an 8x dose. The 1x fresh weight of the putative populations did not differ from 0x. LD50 of imazapyr+imazamox (g ai ha-1) for each biotype was: S, 18.86 + 4.79; DB, 82.48 + 20.93; A, 179.36 + 45.51; and P, 550.88 + 139.79. The three resistant populations exhibited a single-point mutation from guanine to thymine, detected in codon 574 of the ALS gene. This mutation confers resistance to ALS inhibitors. This is the first reported case of kochia resistance in Argentina, providing valuable insights that extend beyond sunflower weed management. |
| format | Artículo |
| id | INTA23761 |
| institution | Instituto Nacional de Tecnología Agropecuaria (INTA -Argentina) |
| language | Inglés |
| publishDate | 2025 |
| publishDateRange | 2025 |
| publishDateSort | 2025 |
| publisher | Universidad de Concepción, Chile |
| publisherStr | Universidad de Concepción, Chile |
| record_format | dspace |
| spelling | INTA237612025-09-11T11:48:58Z First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing Montoya, Jorgelina Ceferina Fabressi, Esteban E. Yanniccari, Marcos Malezas Herbicida con Imidazolinona Herbicidas Imazapir Ensayo Biológico Girasol Weeds Imidazolinone Herbicides Herbicides Imazamox Imazapyr Bio-Assays Sunflowers Bassia scoparia Kochia (Bassia scoparia (L.) A. J. Scott.) is a problematic weed. In Argentina, farmers have recently experienced poor control over imidazolinone-resistant sunflowers, specifically the sensitivity of putative kochia resistant plants to imidazolinone herbicides. Seeds from putative resistant populations from Pellegrini (P), De Bary (DB), and 30 de Agosto (A) and a known susceptible (S) population from Col. Martín Fierro were sown in pots. A mixture of imazapyr (Clearsol® WG 80%) and imazamox (Trigosol WG 70%) was sprayed when plants reached approximately 6 cm in height and 10-leaf stage using a boom sprayer. A trial was conducted to determine the response of kochia to the recommended doses (1x) of imazapyr 80.00 g ai ha-1 + imazamox 20.30 g ai ha-1. Plants were harvested 30 days after treatment to determine fresh shoot weight. A dose–response experiment was performed using imazapyr + imazamox at concentrations of 0x, 1/4x, 1/2x, 1x, 2x, 4x, and 8x. Partial ALS gene amplification was performed using leaves of plants that survived an 8x dose. The 1x fresh weight of the putative populations did not differ from 0x. LD50 of imazapyr+imazamox (g ai ha-1) for each biotype was: S, 18.86 + 4.79; DB, 82.48 + 20.93; A, 179.36 + 45.51; and P, 550.88 + 139.79. The three resistant populations exhibited a single-point mutation from guanine to thymine, detected in codon 574 of the ALS gene. This mutation confers resistance to ALS inhibitors. This is the first reported case of kochia resistance in Argentina, providing valuable insights that extend beyond sunflower weed management. EEA Anguil Fil: Montoya, Jorgelina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Anguil; Argentina Fil: Fabressi, Esteban E. Universidad Nacional de La Pampa. Facultad de Agronomía; Argentina Fil: Yanniccari, Marcos. Instituto Nacional de Tecnología Agropecuaria (INTA). Chacra Experimental Integrada Barrow; Argentina Fil: Yanniccari, Marcos. Universidad Nacional de La Pampa. Facultad de Agronomía; Argentina Fil: Yanniccari, Marcos Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina 2025-09-10T14:16:52Z 2025-09-10T14:16:52Z 2025-08 info:ar-repo/semantics/artículo info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://hdl.handle.net/20.500.12123/23761 https://revistas.udec.cl/index.php/chjaas/article/view/20256 0719-3882 0719-3890 https://doi.org/10.29393/CHJAAS41-33FRFA30033 eng info:eu-repograntAgreement/INTA/2023-PD-L03-I094, Gestión ambiental de los agroquímicos: manejo, mitigación y remediación info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) application/pdf Universidad de Concepción, Chile Chilean Journal of Agricultural & Animal Science 41 (2) : 371-380. (August 2025) |
| spellingShingle | Malezas Herbicida con Imidazolinona Herbicidas Imazapir Ensayo Biológico Girasol Weeds Imidazolinone Herbicides Herbicides Imazamox Imazapyr Bio-Assays Sunflowers Bassia scoparia Montoya, Jorgelina Ceferina Fabressi, Esteban E. Yanniccari, Marcos First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing |
| title | First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing |
| title_full | First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing |
| title_fullStr | First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing |
| title_full_unstemmed | First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing |
| title_short | First report of imidazolinone-resistant Bassia scoparia in Argentina : evidence from dose-response bioassays and ALS gene sequencing |
| title_sort | first report of imidazolinone resistant bassia scoparia in argentina evidence from dose response bioassays and als gene sequencing |
| topic | Malezas Herbicida con Imidazolinona Herbicidas Imazapir Ensayo Biológico Girasol Weeds Imidazolinone Herbicides Herbicides Imazamox Imazapyr Bio-Assays Sunflowers Bassia scoparia |
| url | http://hdl.handle.net/20.500.12123/23761 https://revistas.udec.cl/index.php/chjaas/article/view/20256 https://doi.org/10.29393/CHJAAS41-33FRFA30033 |
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