Study Fitness of Resistant and Susceptible Biotypes of Wild Mustard (Sinapis arvensis) Biotypes to Acetolactate Synthase (ALS) Inhibitor in Competition and Non-Competition with Wheat

This research was conducted to study the relative fitness of wild mustard biotypes of Khoozestan, Golestan and Kermanshah provinces that are resistant to Acetolactate Synthase (ALS) Inhibitors. Green-house experiments were conducted in two parts. In the first part, plant dry matter, leaf area and plant height change of resistant and susceptible biotypes of each province were compared under no competition with wheat condition. In the second part, growth ability of resistant and susceptible biotypes of each province, growth ability and yield of wheat were studied under competition conditions. According to the results, resistant biotype Ker-2 had significantly higher than susceptible biotype Ker-1, but there was no significant difference between them on the point of final height and dry weight per plant. Resistant biotypes of Golestan and Khoozestan (Kh5 & G3) were lower than susceptible biotypes of these provinces (Kh3 & G9) on the point of mentioned three criteria, significantly under competition with wheat condition. Resistant biotypes of Ker-2 and susceptible biotypes of Ker-1 had no significant difference on the point of ability of competition with wheat. Relative interference index of the two biotypes of Kermanshah were not significantly, different. Finally, difference of growth and yield of wheat were not significant in competition with these two biotypes. According to the results of Golestan and Khoozestan, susceptible biotypes of them (Kh3 & G9) had significantly higher growth and interference index than resistant biotypes (Kh5 & G3) in competition with wheat. Also, wheat had higher grain growth and yield in competition with resistant biotypes rather than susceptible biotypes. Finaly, results showed that among the three resistant biotypes, only Ker-2 had the same competition and growth ability to susceptible biotypes. Therefor it, could disperse rapidly and make high interference due to its resistance to ALS inhibitors.