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ARS Home » Pacific West Area » Salinas, California » Crop Improvement and Protection Research » Research » Publications at this Location » Publication #379761

Research Project: Management of Pathogens for Strawberry and Vegetable Production Systems

Location: Crop Improvement and Protection Research

Title: Epidemiology of spinach downy mildew

item Klosterman, Steven

Submitted to: Meeting Abstract
Publication Type: Other
Publication Acceptance Date: 11/10/2020
Publication Date: 11/10/2020
Citation: Klosterman, S.J. 2020. Epidemiology of spinach downy mildew. University of California Cooperative Extension, Monterey County, Online Pest Management Series, November 10, 2020, Salinas, California.

Interpretive Summary:

Technical Abstract: Spinach downy mildew is caused by Peronospora effusa, an obligate oomycete pathogen. In conventional spinach production, downy mildew is effectively controlled using fungicides, but control options in organic production are limited since fungicides are not available for use in organic production. The development of disease resistant cultivars is key for disease control in organic spinach production. However, P. effusa often overcomes resistance in the field as new races of the pathogen can occur with different pathogenic capabilities. Since P. effusa produces both long-lived oospores and sporangia, tracking primary inoculum sources in seed can be useful to limit the introduction of the pathogen into growing regions, and studies are underway that examine the rate of seed transmission and survival of oospores and sporangia, and examination of airborne inoculum loads. Increasing our understanding of spinach downy mildew epidemiology is essential to develop new approaches for integrated disease management.