Kochia scoparia, herbicide resistance

Primiani, M.M., J.C. Cotterman, and L.L. Saari (1990). Resistance of kochia (Kochia scoparia) to sulfonylurea and imidazolinone herbicides. Weed Technol., 4 169-172. 

Saari, L.L., J.C. Cotterman, and M.M. Primiani (1990). Mechanisms of sulfonylurea herbicide resistance in the broadleaf weed Kochia scoparia. Plant Physiol., 93 55-61. 

Resistant biotypes being reported in the early 1990s were selected by chlorsul-furon or metsulfuron-methyl in wheat-growing areas or by sulfometuron-methyl in non-crop areas. While resistance of Lolium rigidum to ALS-inhibitors was attributed to enhanced herbicide metabolism [50] it was shown, for Lolium perenne and dicotyledonous species like Stellaria media, Kochia scoparia, Scdsola iberica and Lactuca serriola, that resistant biotypes had a mutated ALS with reduced susceptibility to ALS-inhibitmg herbicides [51-53]. The IC50S for sulfonylureas, which were determined in vitro with ALS isolated from Stellaria media, Salsola iberica and Lolium perenne, increased 4- to 50-fold in the resistant biotypes. Smaller increases, about 2- to 7-fold, were determined in the same biotypes for the imidazo-linone herbicide imazapyr [53]. 

Selection of multiple resistance after sequential use of different herbicides has been described for a biotype of Kochia scoparia from North America. Many years... 

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