Different cross-resistance patterns to AHAS herbicides of two tribenuron-methyl resistant flixweed (Descurainiasophia L.) biotypes in China

Pestic Biochem Physiol. 2014 Jun:112:26-32. doi: 10.1016/j.pestbp.2014.05.003. Epub 2014 Jun 2.

Abstract

Flixweed (Descurainiasophia L.) is a troublesome weed in winter wheat fields in China. Two flixweed accessions, HB08 and HB16 with a Pro-197-Leu and Pro-197-Ser AHAS-mutation respectively, have evolved very high levels resistance to sulfonylurea (SU) herbicide, tribenuron-methyl. Cross resistance of HB08 and HB16 to AHAS herbicides of SU, imidazolinone (IMI), triazolopyrimidine (TP) and pyrimidinyl-thiobenozoate (PTB) families was investigated by dose-response experiments. In addition, the effects of AHAS herbicides on the activity of AHAS extracted from HB08 and HB16 plants were evaluated. HB16 exhibited cross resistance to SU herbicides halosulfuron-methyl and triasulfuron, TP herbicides flumetsulam and penoxsulam, but displayed more sensitivity to IMI herbicide imazethapyr. By contrast, HB08 only showed cross resistance to SU herbicides halosulfuron-methyl and triasulfuron. The in vitro sensitivity of AHAS to AHAS herbicides is consistent with the results of dose-response experiments and the estimated Pearson's r values for HB08 and HB16 are 0.996 and 0.912 respectively. These indicated that altered AHAS sensitivity was responsible mainly for cross resistance patterns observed in the two resistant biotypes.

Keywords: AHAS enzyme; AHAS herbicides; Cross resistance; Flixweed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetolactate Synthase / antagonists & inhibitors
  • Acetolactate Synthase / genetics*
  • Acetolactate Synthase / metabolism
  • Amino Acid Substitution
  • Arylsulfonates / pharmacology*
  • Brassicaceae / classification
  • Brassicaceae / genetics*
  • Brassicaceae / growth & development
  • China
  • Dose-Response Relationship, Drug
  • Herbicide Resistance / genetics*
  • Imidazolines / pharmacology
  • Mutation
  • Plant Proteins / antagonists & inhibitors
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Plant Weeds / classification
  • Plant Weeds / genetics*
  • Plant Weeds / growth & development
  • Pyrimidines / pharmacology
  • Species Specificity
  • Sulfonylurea Compounds / pharmacology
  • Triazoles / pharmacology

Substances

  • Arylsulfonates
  • Imidazolines
  • Plant Proteins
  • Pyrimidines
  • Sulfonylurea Compounds
  • Triazoles
  • halosulfuron methyl
  • metsulfuron methyl
  • triasulfuron
  • Acetolactate Synthase