Wild oat (Avena ludoviciana) is a prevalent weed in wheat fields of Iran. Accordingly, ACCase (Acetyl-CoA carboxylase) inhibitors, which include aryloxyphenoxypropionate (APP), cyclohexanedione (CHD) and phenylpyrazolin (PPZ) herbicides, are selectively applied to control wild oat and other weedy grasses. The continued reliance on ACCase inhibitor herbicides during the last two decades is associated with the extensive appearance of resistant wild oat biotypes. Resistance across ten ACCase-inhibiting herbicides was characterized in  fteen Avena ludoviciana biotypes from the southern grain belt of Iran (Fars and Khuzestan Provinces). Whole plant bioassays were conducted at the Iranian Research Institute of Plant Protection, Tehran, during 2014-2015 to determine the diversity of cross-resistance patterns to diclofop, fenoxaprop-P, clodinafop, quizalofop-R, haloxyfop, sethoxydim, cycloxydim, clethodim, pinoxaden and clodinafop + pinoxaden among wild oat populations. The di erent biotypes showed di erent ranges of resistance to given herbicides. Thus based on results, all biotypes (exception of ES that was susceptible to clodinafop) exhibited crossresistance to diclofop, fenoxaprop-P and clodinafop. Moreover, nearly 53% of populations were resistant to quizalofop-R, whereas 27% were resistant to haloxyfop. Two biotypes of four sethoxydim-resistant populations showed cross resistance to cycloxydim. However, none of the wild oat biotypes were resistant to clethodim or pinoxaden. Cross-resistance in wild oat within the APP herbicides at 75% was much greater than within CHD herbicides at 13%. It is evident that most wild oat populations from the grain production belt of Iran have evolved resistance to a number of ACCase-inhibiting herbicides. Pinoxaden and clethodim can be suitable alternatives to control ACCase-resistant wild oats biotypes when combined with herbicide rotation and non-chemical weed management.

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