title: IMI resistance associated to crop-weed hybridization in a natural Brassica rapa population: characterization and fate.
abstract: Wild turnip (Brassica rapa) is a common weed and a close relative to oilseed rape (Brassica napus). The Clearfield® production system is a highly adopted tool which provides an alternative solution for weed management, but its efficiency is threatened by gene transfer from crop to weed relatives. Crop-weed hybrids with herbicide resistance were found in the progeny of a B. rapa population gathered from a weedy stand on the borders of an oilseed rape (B. napus) imidazolinone (IMI)-resistant crop. Interspecific hybrids were confirmed by morphological traits in the greenhouse and experimental field, survival after imazethapyr applications, DNA content through flow cytometry, and pollen viability. The transference of herbicide resistance was demonstrated even in a particular situation of pollen competition between both an herbicide-resistant crop and a non-resistant crop. However, IMI resistance was not found in further generations collected at the same location. These results verify gene transmission from oilseed rape to B. rapa in the main crop area in Argentina where resistant and susceptible varieties are found and seed loss and crop volunteers are common. Hybridization, introgression, and herbicide selection would be associated with the loss of effectiveness of IMI technology.
authors.affiliation: Departamento de Agronomía, Universidad Nacional del Sur and CERZOS-CCT, 8000, Bahía Blanca, Argentina. msureta@uns.edu.ar.
authors.forename: M S
authors.initials: MS
authors.lastname: Ureta
authors.affiliation: Departamento de Agronomía, Universidad Nacional del Sur and CERZOS-CCT, 8000, Bahía Blanca, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Torres Carbonell
authors.affiliation: Departamento de Agronomía, Universidad Nacional del Sur and CERZOS-CCT, 8000, Bahía Blanca, Argentina.
authors.forename: C
authors.initials: C
authors.lastname: Pandolfo
authors.affiliation: Departamento de Agronomía, Universidad Nacional del Sur and CERZOS-CCT, 8000, Bahía Blanca, Argentina.
authors.forename: A D
authors.initials: AD
authors.lastname: Presotto
authors.affiliation: EEA INTA, Hilario Ascasubi, Ruta 3 km 794, Buenos Aires, Argentina.
authors.forename: M A
authors.initials: MA
authors.lastname: Cantamutto
authors.affiliation: Departamento de Agronomía, Universidad Nacional del Sur and CERZOS-CCT, 8000, Bahía Blanca, Argentina.
authors.forename: M
authors.initials: M
authors.lastname: Poverene
mesh_terms: D001118:Argentina; D029688:Brassica napus / Q000187:drug effects* / Q000235:genetics*; D029741:Brassica rapa / Q000187:drug effects* / Q000235:genetics*; D018744:DNA, Plant / Q000032:analysis; D004784:Environmental Monitoring; D005434:Flow Cytometry; D053209:Herbicide Resistance / Q000235:genetics*; D006540:Herbicides / Q000633:toxicity*; D006824:Hybridization, Genetic; D048288:Imidazolines / Q000633:toxicity*; D010641:Phenotype; D030821:Plants, Genetically Modified; D011058:Pollen / Q000187:drug effects; D012639:Seeds / Q000187:drug effects; D058728:Weed Control / Q000379:methods
chemical_list: D018744:DNA, Plant; D006540:Herbicides; D048288:Imidazolines
keywords: Flow cytometry; Herbicide resistant; Morphology; Off-type plants; Volunteers