The efficacy of reduced -411.5 and 617.2 a.i. ha-1- and recommended -823.0 g a.i. ha-1- doses of phenmedipham + desmedipham + ethofumesate on the control ofAmaranthus retroflexus, Amaranthus blitoides, Chenopodium album, and Tribulus terrestris in sugar beet fieldwere investigatedwhen tank-mixed with and without Adigor -0.5% v/v-, Ammonium sulphate -2% v/v-, Citogate -0.2% v/v-, D-Octil-0.3% v/v-, Hydro-Max -0.5% v/v-, and Volck -0.5% v/v-.When the herbicide was applied alone, there was no significant difference between the doses of 617.2 and 823.0 g a.i. ha-1 in reducing the total weed density and biomass. Significantly, the adjuvants decreased the total weed density and biomass. However, there was no significant difference among the performance of adjuvants. The sugar beet root and sucrose yield were increased significantly by increasing herbicide dose due to an improvement in controlling the weeds. Although the efficacy of herbicide was influenced in a similar manner by all adjuvants, the best results were observed as following: the root yield was increased up to 9.66% -71.31 Mgha-1- byapplying the recommended dose of phenmedipham + desmedipham + ethofumesateplus Adigor relative to weed-free check-64.68 Mgha-1- whereas the sucrose yield was increased up to 26.48% -13.21 t ha-1- byapplying the recommended dose of phenmedipham + desmedipham + ethofumesateplus HydroMax relative to weed-free check -10.45 t ha-1-. From an economicand ecological standpoint, these two adjuvants can besuggested to optimize the recommended dose of phenmedipham + desmedipham + ethofumesatein weed management.

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