Soft red winter wheat tolerance to and Italian ryegrass control by a mixture of AE F130060 00 plus AE F115008 00 plus safener applied in water or urea ammonium nitrate (UAN) were evaluated in separate experiments. In the tolerance experiment, wheat responded similarly to AE F130060 00 plus AE F115008 00 at 12.5 plus 2.5 and 25 plus 5 g ai/ha, respectively, applied in water. The herbicides plus nonionic surfactant (NIS) applied in water injured weed-free, five- to seven-tiller wheat 3% or less and did not affect yield. Greater injury occurred with application in UAN, and yield was reduced 11% as result of fewer kernels per spike. NIS added to the herbicides in UAN increased weed-free wheat injury but had no effect on yield. AE F130060 00 plus AE F115008 00 controlled both diclofop-susceptible and -resistant Italian ryegrass. Greater control was obtained with application in UAN as compared with application in water, and NIS increased control. Yield of Italian ryegrass–infested wheat treated with herbicides plus NIS in UAN was similar to or greater than yield when herbicides plus NIS were applied in water.
Nomenclature: AEF 115008 00 (proposed name iodosulfuron-methyl-sodium), 4-iodo-2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino]sulfonyl]benzoic acid methyl ester; AE F130060 00 (proposed name mesosulfuron-methyl), methyl 2-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-4-[[(methylsulfonyl)amino]methyl] benzoate; Italian ryegrass, Lolium multiflorum Lam. Marshall #3 LOLMU; wheat, Triticum aestivum L. ‘Coker 9704’.
Additional index words: Herbicide carriers, surfactant rates, yield components, LOLMU.
Abbreviations: GS, Feekes growth stage; NIS, nonionic surfactant; UAN, urea ammonium nitrate; WAT, weeks after treatment.
