Determination of the efficiency of different herbicides used in sugar beet on yield and weed control

The aim of this research was to examine the possibilities of controlling weeds with herbicide applications without the need for hoeing in sugar beet cultivation. In the study carried out in Eskişehir conditions in 2022, ALS-inhibitor herbicide-resistant sugar beet cultivar Smart Sephora and herbicides of Metamitron+Quinmerac (M+Q) and ALS inhibitor (Foramsulfuron+Thiencarbazone-methyl) herbicides were used. Ten herbicide applications, which were created with the application times and doses of the two herbicides, (T1: M+Q at preemergence (PE), T2: ALS inhibitor at PE, T3: M+Q at four leaf stage (V4), T4: 100 mL/da ALS at V4, T5: 150 mL/da ALS at V4, T6: M+Q at PE + M+Q at V4, T7: M+Q at PE + 50 mL/da ALS at V4, T8: 50 mL/da ALS at PE + 75 mL/da ALS at V4, T9: ALS (50 mL/da) at V2 + ALS (50 mL/da) at V4, T10: ALS (50 mL/da) at V2 + ALS (50 mL/da) at V4 + adhesive) were arranged. The results of the research showed that the highest root weight was determined with 1303 g in T10 and the highest yield was determined in T8 application. In terms of digestion, the highest value (14.5%) was obtained from T3 application. The most common weeds in the experimental area were rough cocklebur (Xanthium strumarium L., 57.5%), lambsquarters (Chenopodium album L., 37.5%), redroot pigweed (Amaranthus retroflexus L., 17.5%) and cockspur grass (Echinochloa crus-galli L., 15.0%), respectively. The lowest weed density was determined in applications of T8 and T5. Negative correlations were calculated between the yield of sugar beet and the density of weed species. Negative and significant relationships were calculated between yield and lambsquarters (r= -0.684**) and rough cocklebur density (r= -0.641**). As a result, it was concluded that herbicide application (T8) of 50 mL/da ALS at PE + 75 mL/da ALS at V4 period should be recommended for effective weed control in sugar beet.