Pacific Northwest 1998 An Online Guide to Plant Disease Control
 
Mulberry (Morus sp.) -- Bacterial Blight
Cause: Pseudomonas syringae pv. mori, a bacterium favored by cool, wet weather in spring. The OSU Plant Disease Clinic has diagnosed this disease several times.
Symptoms: Leaf spots are small and brown-black, usually with yellow haloes. Infected leaves are often distorted. Infected buds may become disfigured as they swell. Young shoots may show rapid necrosis and dieback. Occasional stem cankers occur which may exude ooze. Infected bushes and trees often appear stunted.
Cultural control:
  1. Minimize wounds to limbs and new shoots.
  2. Prune out and destroy infected shoots and branches during the late dormant season.
  3. Space plantings to provide good air circulation.
Chemical control: The following are registered on weeping mulberry, do not use on edible types.

  1. Copper-Count-N at 1 quart/100 gal water. 12-hr reentry.
  2. Kocide 2000 T/N/O at at 0.75 to 3 lb/A (or 1 to 3 Tbsp/1,000 sq ft) dormant or at 0.75 to 2 lb/A when new growth is present. 24-hr reentry.
  3. Junction at 1.5 lb/100 gal water. 24-hr reentry.
  4. Nu-Cop 50 DF at 1 lb/100 gal water. 24-hr reentry.
Content edited by: Jay W. Pscheidt on January 1, 2009
 
Edited by Jay W. Pscheidt, Extension Plant Pathology Specialist, Oregon State University, Corvallis, OR 97331-2903 World Wide Web site and scripting by Eric T. Peterson and Bryan Capitano at Capitano NetSolutions, Inc., HTTP://www.capitanonetsolutions.com. Access the Plant Disease Control Guide on-line at HTTP://plant-disease.ippc.orst.edu/

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