Evaluating the Effectiveness of Various Herbicides for Managing Broadleaf Weeds in Faba Bean (Vicia faba L.)

Faba bean growth and yield are constrained by weeds. Thus, field experiments were conducted in Khorramabad, Iran in 2020-2021 to evaluate the effect of trifluralin 960 g ai ha^–1 pre-plant applications (PPI), imazethapyr 100 g ai ha^–1 pre-plant applications (PPI), imazethapyr 100 g ai ha^–1 plus one hand weeding (OHW), imazethapyr100 g ai ha^–1 POST (post-emergence herbicide), bentazon 960 g ai ha^–1 POST, oxyflorfen 192 g ai ha^–1 preemergence (PRE), oxyflorfen PRE + OHW, diclosulam 21 g ai ha–1 PRE, diclosulam PRE plus OHW, one or two hand weeding on weed control and yield in faba bean. Weeds, such as safflower, wild mustard, cow cockle, and three-horn bedstraw were dominant in both years. Weed biomass in uncontrolled plots was 173 g m^-2 in 2020 and 145 g m^-2 in 2021. The lowest weed biomass was observed in diclosulam PRE + OHW, bentazon POST, and two hand weeding treatments. Imazethapyr PPI, trifluralin PPI, and imazethapyr POST herbicides negatively affected faba bean yield. In 2020 and 2021, Diclosulam + OHW decreased total weed density by 85% and 82%, respectively, compared to the untreated sample (control). These ideas resulted in 53% and 61% yield reductions in the weedy check plots compared to the weed-free control plots in 2020 and 2021, respectively. All herbicides resulted in minor damage to the beans, with diclosulam and OHW + diclosulam exhibiting the least impact.