Bacterial leaf spot

Pest: Bacterial leaf spot (Pseudomonas ssp. and Xanthomonas ssp.)

Pest Type: Infectious disease, bacterium

Major Identifying Features: Disease symptoms include water-soaked lesions on foliage that darken with age, lesions may be bordered by the leaf venation

Life Cycle: Bacterium is highly dependant on wet, cool conditions for infection and disease development

Pest Rating: Moderate

Management Rating: Moderate

Host/Season/Outbreak Information: Host include Astilbe, Chrysanthemum, Delphinium, Echinacea, Heuchera ,Hypericum, Rudbeckia, and many other plants, bacteria on the plant surface are easily spread to nearby plants by splashing water from rain and irrigation, asymptomatic plants can serve as a source of inoculum, disease symptoms develop once the pathogen reaches high population levels on the plant surface, symptoms appear in April to May

Damage Information: Leaves drop prematurely, cankers can build

Management Options: Prevention by sanitation is especially important, workers should wash their hands after handling diseased plants, foliage should not be handled when it is wet, mechanical control by destroying symptomatic plants, cultural control by avoiding overhead irrigation and minimizing leaf wetness, chemical control with copper-based products might be helpful

Sources:

http://www.ipm.ucanr.edu

http://www.imp.msu.edu

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s