title: Acetohydroxyacid synthase (AHAS) in vivo assay for screening imidazolinone-resistance in sunflower (Helianthus annuus L.).
abstract: The objective of this work was to evaluate the in vivo acetohydroxyacid synthase (AHAS) activity response to imidazolinones and its possible use as a selection method for evaluating AHAS inhibitor resistance. In vivo AHAS assay and the comparison of parameters from dose-response curves have been used as a valid tool for comparing sunflower lines and hybrids differing in imidazolinone resistance. The sunflower resistant genotypes evaluated here were 100-fold and 20-fold more resistant compared with the susceptible line for imazethapyr and imazapyr, respectively. This assay also allowed discrimination of homozygous from heterozygous genotypes for I(mr1) locus that codify for the catalytic subunit of AHAS. The in vivo AHAS assay described in this study was useful for the selection of sunflower genotypes differing in herbicide resistance and could be a useful tool when breeding for imidazolinone resistance in sunflower.
authors.affiliation: CONICET, Cátedra de Genética, Facultad de Ciencias Agrarias, Universidad Nacional de Rosario, Campo Experimental J. F. Villarino, CC 14, S2125ZAA Zavalla, Argentina. tvega@unr.edu.ar
authors.forename: T
authors.initials: T
authors.lastname: Vega
authors.forename: G
authors.initials: G
authors.lastname: Breccia
authors.forename: M
authors.initials: M
authors.lastname: Gil
authors.forename: R
authors.initials: R
authors.lastname: Zorzoli
authors.forename: L
authors.initials: L
authors.lastname: Picardi
authors.forename: G
authors.initials: G
authors.lastname: Nestares
mesh_terms: D000095:Acetolactate Synthase / Q000037:antagonists & inhibitors / Q000235:genetics*; D017343:Genes, Plant; D056426:Genetic Loci; D005838:Genotype; D006368:Helianthus / Q000201:enzymology / Q000235:genetics*; D053209:Herbicide Resistance / Q000235:genetics*; D006540:Herbicides; D006579:Heterozygote; D006720:Homozygote; D006824:Hybridization, Genetic; D007093:Imidazoles; D009525:Niacin / Q000031:analogs & derivatives; D009539:Nicotinic Acids; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics*; D021122:Protein Subunits
chemical_list: D006540:Herbicides; D007093:Imidazoles; D009539:Nicotinic Acids; D010940:Plant Proteins; D021122:Protein Subunits; D009525:Niacin; C093630:imazethapyr; C076656:imazapyr; D000095:Acetolactate Synthase