Optimizing Sulfosulfuron and Sulfosulfuron Plus Metsulfuron-methyl Activity when Tank-Mixed with Vegetable Oil to Control Wild Barley (Hordeum spontaneum Koch.)

Wild barley has invaded wheat fields ever since flamprop-isopropyl was outdated in Iran. Newly developed herbicides such as sulfosulfuron or sulfosulfuron plus metsulfuron-methyl can control it at higher than recommended dosages, but causing significant wheat injury. Hence, two dose-response experiments were conducted to evaluate their efficacy when tank-mixed with thirteen different vegetable oils, at the Ferdowsi University of Mashhad, Iran, during ۲۰۱۳. Moreover, a wheat cultivar (Gaskogen) was also treated with effective dose of ۹۰% (ED۹۰) of both herbicides (۲۱.۴۴ grams active ingredient (g ai) of sulfosulfuron ha-۱ and ۴۱.۹۵ g ai of sulfosulfuron plus metsulfuron-methyl ha-۱) with and without each vegetable oil to check selectivity. Averaged over vegetable oils, the effective dose of ۵۰% (ED۵۰) was decreased ۲.۶- and ۳.۰-fold with sulfosulfuron and sulfosulfuron plus metsulfuron-methyl, respectively. Among the evaluated vegetable oils, cottonseed and coconut oil were the best ones to enhance the efficacy of both herbicides. The castor oil had the least effect. A negative correlation was observed between the efficiency of vegetable oils and its unsaturated/saturated fatty acids ratio. No phytotoxic effect on wheat was observed when these herbicides were applied with or without the vegetable oils.

کلیدواژه ها:

Crop selectivity ، Herbicide efficacy ، Penetrant agent ، Vegetable oils ، Wild barley