Abstract:

Avena sterilis L. subsp ludoviciana (Durieu) Gillet and Magne (AVELU) is among the most common and economically important grass weed species, especially in wheat fields of Turkey; therefore, the herbicides with the same mode of action (ACCase and ALS/AHAS inhibitors) are used to control have been successively applied without incessant by farmers. A study was conducted to find out the extent of wild oat problems throughout Turkey including herbicide resistance. This paper includes results of determining the herbicide resistance status of AVELU populations to ACCase and ALS inhibitors that are fenoxaprop (Fen), pinoxaden (Pin), tralkoxydim (Tra), mesosulfuron+iodosulfuron (MeI), and proxycarbazone+mesosulfuron (PrM). AVELU seeds were collected from 213 wheat fields throughout Turkey in 2014?2015 and the response to selected five herbicides was tested under screen-house. Dose-response tests showed that only 42 populations were controlled by all five herbicides. The number of populations that were not controlled varied by herbicides, which were 150, 48, 25, 100, and 100 populations for Fen, Pin, Tra, MeI, and PrM, respectively. Nine populations were resistant to all herbicides and 72 to four of herbicides out of 155 multiple resistance populations. The high number of multiple resistances and higher resistance indexes show the seriousness of the problem. Although resistance to MeI and Tra herbicides are still developing, Fen resistance seems completed and reached moderate and high resistance levels. Integrated weed management is an inevitable challenge to sustain wheat production, a staple crop for Turkey.

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