Pseudomonas Blight
Pseudomonas syringae pv. syringae
14 host plants
Last updated
This profile synthesizes data from multiple published sources. Expert field review is in progress.
Pseudomonas blight causes blighting and dieback of shoots and foliage during cool, wet conditions. This bacterial disease spreads through water splash and contaminated tools. Remove infected branches and disinfect tools. Improve air circulation through pruning. Avoid overhead watering and reduce leaf wetness. Apply copper fungicides preventively if needed. This blight is most damaging during cool, wet springs when flower and shoot development is rapid. Monitor plants closely during vulnerable periods.
Avoid excessive and/or late fertilization. Plant resistant cultivars such as Chilcotin, Newburgh, or Nova.
Quick Reference
Management
Spring, during the development of new laterals and primocane shoots. Young succulent growth is most vulnerable during cold wet periods. Disease occurs occasionally in the Pacific Northwest and is rarely seen on blackberry." # Source: PNW Plant Disease Management Handbook (Raspberry - Pseudomonas Blight)
Cold, moist weather near freezing (31-33°F / 0-1°C). Outbreaks are strongly associated with frost events during the spring growth period. Succulent growth from high nitrogen fertilization is more susceptible. P. syringae produces ice nucleation proteins that promote frost damage, creating entry wounds for bacterial colonization." # Source: PNW Plant Disease Management Handbook (Raspberry - Pseudomonas Blight)
Cultural Controls
- Avoid excessive and/or late fertilization.
- Plant resistant cultivars such as Chilcotin, Newburgh, or Nova.