Resistance Level Of Alopecurus Aequalis Sobol.to Quizalofop-p-ethyl In Oil Rape In Hunan Province

Alopecurus aequalis Sobol is a kind of annual or biennial gramineous weed. In our country, especially in the field of barley, wheat and oil rape, it is seriously harmful and stubbornly difficult to remove. At present, it is mainly used acetyl coenzyme carboxylase inhibitor herbicide to prevent Alopecurus aequalisSobol in broad-leaf field, like haloxyfop-R-methyl, quizalofop-p-ethyl,clethodim and so on. The resistance level and mechanism of Alopecurus aequalis Sobol to quizalofop-p-ethyl were tested in this study.1. The resistance level of Alopecurus aequalis Sobol. to quizalofop-p-ethyl was assessed by two methods:seed bioassay and whole-plant bioassay. The result of seed bioassay showed that the highest relative resistance factor of Taoyuan Town in Changde was10.50. All the other potencial resistant biotypes resistance factor ranging from2.01-7.09, which were still sensitive to quizalofop-p-ethyl. The results of whole-plant bioassay showed that the relative resistance factor of biotype from Taoyuan Town in Changde was also the highest, which was25.30, while those of other potential resistant biotypes were from2.43-9.47.2. The enzymology mechanism of Taoyuan Town resistant biotype and Nanjing Agricultural University susceptible biotype was discussed by the research on the important metabolic enzyme glutathione-s-transferase(GSTs), protective enzyme catalase(CAT), peroxidase(POD) and superoxide dismutase(SOD).The GSTs’activity of resistance biotype was higher than those of susceptible biotype on fifth day, which indicated that the difference of metabolizable ability of GSTs were important reasons of the resistance to quizalofop-p-ethyl, while there were no deffirences between resistance biotype and susceptible biotype’s activities of CAT, POD and SOD.3. The resistance mechanism on molecular level was detect by using PCR technology and comparing the amino acid sequence of resistant and sensitive plants. The comparasion of ACCase sequences between the resistance and sensitive biotypes showed that the amino acid sequence of resistant biotype had one more Ala than sensitive biotype had, further verification is needed to figure out the relationship between resistance level and target gene’s mutation.