This project supports the mission of the agricultural experiment station by addressing the hatch act area(s) of: home economics and family life.as a quarantine pest that can cause significant yield…

The University of California, Davis received a $622,715 Project Grant from the National Institute of Food and Agriculture (NIFA) under the Integrated Programs (CFDA 10.303) to develop and advance systems-based integrated pest management (IPM) strategies for branched broomrape (Orobanche ramosa), a parasitic weed of significant regulatory concern affecting California tomato production. The award, issued on September 16, 2025, with a completion date of September 15, 2028, supports the Agricultural Experiment Station's mission in home economics and family life. The project addresses the critical need to contain broomrape's spread beyond Yolo and San Joaquin counties, where the pest currently exists, to the approximately 10 additional California counties where tomatoes are cultivated.

The primary deliverables include the development and improvement of science-based best management practices (BMPs) for farm equipment sanitation and broomrape management protocols that align with California Department of Food and Agriculture's newly launched compliance agreement for equipment sanitation. Research efforts focus on resolving outstanding challenges with current equipment sanitation practices through systems-based approaches, with secondary outcomes addressing co-management of soil-borne pathogen spread. The project builds on prior progress that established the first science-based equipment cleaning BMP and supported over a dozen tomato producers in improving sanitation methods, as well as the construction of trailer wash stations at multiple canneries in preparation for the transition from voluntary to mandatory compliance in 2026.

This project supports the mission of the agricultural experiment station by addressing the hatch act area(s) of: home economics and family life.as a quarantine pest that can cause significant yield loss, the parasitic weed broomrape (orobanche ramosa) represents a major industry concern for US growers, especially california tomatoes-the most affected state and crop in the country. At the start of this project, broomrape was only present in a single county (yolo county); IT is now also in SAN joaquin county, but there remains opportunity to slow its spread in affected regions and prevent establishment in the other ~10 counties where tomatoes are grown. Progress has already been made to develop the first science-based BMP for cleaning farm equipment and has provided critical support for over a dozen tomato producers to improve equipment cleaning methods, as well as support for the construction of trailer wash stations at several canneries. In 2025, the cdfa broomrape launched a compliance agreement under which, in this first year, growers and canneries can voluntarily participate; in 2026, this agreement will become mandatory. As this compliance agreement will include equipment sanitation and broomrape management guidelines, a major goal of this proposed work is to resolve some of the major outstanding challenges with existing practices for equipment sanitation. This integrated project will develop and improve systems-based integrated pest management strategies for branched broomrape (orobanche ramosa) a parasitic weed of regulatory concern; CO-management of soil borne pathogen spread is a secondary outcome. In the past, a significant branched broomrape infestation in california was successfully managed using widespread field fumigation with methyl bromide under a state eradication program. Although mebr quarantine exemptions exist, this key fumigant is prohibitively expensive and challenging to use because of regulations related to environmental damage and human safety concerns. Importantly, soil fumigation approaches to manage soil seedbanks of weeds like branched broomrape or propagules of new diseases is reactive management that occurs only after an infestation is at an economically damaging level. This proposal includes objectives with proactive management goals to reduce the spread of this economically disastrous weed pest, non-fumigant approaches to reduce the risk of successful establishment, and cultural practices and mebr alternative fumigants to manage established populations of the weed. This project improves soil conservation by protecting agricultural soils from broomrape infestation, which can affect crop health long term. Plants are protected by reducing spread and impacts of broomrape on tomatoes and other affected crops. The processing tomato industry benefits by receiving support to develop harvester and cannery cleaning systems. This project improves agricultural sustainability by protecting land from this invasive parasitic weed, using integrated management methods, with emphasis on environmentally friendly tools.