Integrated Management of Crenate Broomrape (Orobanche crenata) in Faba Bean (Vicia faba) Fields of Northern Ethiopia

Crenate broomrape (Orobanche crenata Forsk.) is a major parasitic weed threatening faba bean (Vicia faba L.) production in northern Ethiopia since the early 1990s, with yield losses reaching up to 100%. Despite various control efforts, no single management practice has proven fully effective in mitigating its impact. This study aimed to evaluate integrated management for crenate broomrape in faba bean under naturally infested field conditions and the resultant agroeconomic return. The experiment was conducted at Kutaber and Tach-Gaynt during the 2022 main cropping season. Five treatments with a combination of partially resistant faba bean variety ‘Hashenge’, glyphosate, hand-weeding along with crenate broomrape weedy check and susceptible check ‘Degaga’were used. Besides measuring the level of crenate broomrape infestation and effect on faba bean yield, a partial budget analysis was performed to determine the highest economic return. Results showed that the combined application of Hashenge with glyphosate (0.6 L ha-1) and two or one hand-weeding at ten days interval starting at the crop flowering significantly reduced crenate broomrape infection by 71% and 87%, and improved faba bean grain yield by 80% and 42% compared to the susceptible check at Kutaber and Tach-Gaynt, respectively. Hashenge with glyphosate and two hand-weeding provided the highest net benefit (NB) of ETB 20,330 with marginal rate of return (MRR) of 19.25%, and value to cost ratio (VCR) of ETB 0.196 per unit of investment at Kutaber. The highest NB of ETB 198,240 ha-1 with MRR of 67.41%, and VCR of ETB 2.52 per unit of investment was obtained from Hashenge with glyphosate and one hand-weeding at Tach-Gaynt. Further multi-season and multi-location studies are needed to validate the long-term effectiveness and economic viability of the best performed treatments. Additionally, careful consideration should be given to the sustainability of glyphosate use to minimize potential environmental and resistance-related risks.