title: Evolution and diversity of the mechanisms endowing resistance to herbicides inhibiting acetolactate-synthase (ALS) in corn poppy (Papaver rhoeas L.).
abstract: We investigated the diversity of mechanisms conferring resistance to herbicides inhibiting acetolactate synthase (ALS) in corn poppy (Papaver rhoeas L.) and the processes underlying the selection for resistance. Six mutant ALS alleles, Arg₁₉₇, His₁₉₇, Leu₁₉₇, Ser₁₉₇, Thr₁₉₇ and Leu₅₇₄ were identified in five Italian populations. Different alleles were found in a same population or a same plant. Comparison of individual plant phenotype (herbicide sensitivity) and genotype (amino-acid substitution(s) at codon 197) showed that all mutant ALS alleles conferred dominant resistance to the field rate of the sulfonylurea tribenuron and moderate or no resistance to the field rate of the triazolopyrimidine florasulam. Depending on the allele, dominant or partially dominant resistance to the field rate of the imidazolinone imazamox was observed. Putative non-target-site resistance mechanisms were also likely present in the populations investigated. The derived Cleaved Amplified Polymorphic Sequence assays targeting ALS codons crucial for herbicide sensitivity developed in this work will facilitate the detection of resistance due to mutant ALS alleles. Nucleotide variation around codon 197 indicated that mutant ALS alleles evolved by multiple, independent appearances. Resistance to ALS inhibitors in P. rhoeas clearly evolved by redundant evolution of a set of mutant ALS alleles and likely of non-target-site mechanisms.
authors.affiliation: INRA, UMR1210 Biologie et Gestion des Adventices, 17 rue Sully, F-21000 Dijon, France. delye@dijon.inra.fr
authors.forename: Christophe
authors.initials: C
authors.lastname: Délye
authors.forename: Fanny
authors.initials: F
authors.lastname: Pernin
authors.forename: Laura
authors.initials: L
authors.lastname: Scarabel
mesh_terms: D000095:Acetolactate Synthase / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000235:genetics*; D000483:Alleles; D019943:Amino Acid Substitution; D001483:Base Sequence; D004252:DNA Mutational Analysis; D019143:Evolution, Molecular; D005838:Genotype; D053209:Herbicide Resistance / Q000235:genetics*; D006540:Herbicides / Q000494:pharmacology*; D007093:Imidazoles / Q000494:pharmacology; D008969:Molecular Sequence Data; D009154:Mutation; D010207:Papaver / Q000201:enzymology / Q000235:genetics* / Q000502:physiology*; D010641:Phenotype; D011110:Polymorphism, Genetic; D011743:Pyrimidines / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D013453:Sulfonylurea Compounds / Q000494:pharmacology
chemical_list: D006540:Herbicides; D007093:Imidazoles; D011743:Pyrimidines; D013449:Sulfonamides; D013453:Sulfonylurea Compounds; C413390:florasulam; D000095:Acetolactate Synthase; C494197:imazamox