Online Pesticide License Recertification Seminar Series: Epidemiology and integrated management of bacterial leaf spot

Epidemiology and integrated management of bacterial leaf spot caused by Pseudomonas syringae pv. aptata in table beet and Swiss chard seed production in the Pacific Northwest, 11:00-12:00, Speakers: Marilen Nampijja and Stephanie Crane
Bacterial leaf spot (BLS) of beet and Swiss chard (Beta vulgaris subsp. vulgaris) is caused by the bacterial pathogen Pseudomonas syringae pv. aptata (Psa). The bacterium can cause significant economic losses in Swiss chard, table beet, and sugar beet. In 2017 alone, the incidence of BLS in New York table beet crops was 75%. Given the seedborne nature of this pathogen, the genetic similarity of strains of the pathogen to non-pathogenic strains of P. syringae, the host range of the pathogen (including crops in other plant families than Chenopodiaceae), a federally-funded research project on Psa was initiated in 2019. Over the next 4 years, 18 investigators from 9 institutions in 2 countries will work together to develop an economically-sound, integrated approach to manage BLS across seed and food production systems of host plants in the Chenopodiaceae and Cucurbitaceae, to ensure high-quality seed and food crops. The research objectives of this study include developing pathogen detection and quantification methods for testing seed and other inoculum sources, identifying primary sources of inoculum of Psa in table beet and Swiss chard seed and production fields, clarifying the disease cycle of Psa in different cropping systems and regions, breeding for resistance to BLS, and developing more effective integrated management programs for BLS. The management aspects include determining the location of the pathogen on/in seed, assessing the risks of seed transmission, and evaluating diverse seed treatments as well as in-field production practices to reduce the negative impacts of Psa on our ability to produce healthy Chenopodiaceae and Cucurbitaceae crops. Marilen Nampijja and Stephanie Crane will share information on their respective graduate research projects at WSU on BLS, and how stakeholders can contribute to the overall project.

Please contact AMS.MountVernon@wsu.edu for Zoom details.