Problem Identifier Unit Screen//v.w/ RR Template

Problem Identifier Unit Screen//v.w/ RR Template Bud Rot

Problem
The newly opened young leaves may be partially or entirely blackened, or they may be covered with tiny white spots. The older leaves may be distorted. Often they are covered with yellow or brown spots and streaks. In many cases, the flower buds turn black and die before they open. Entire stalks are often decayed. A sticky substance may coat infected leaf tissue.

Analysis
This plant disease is caused by bacteria (Xanthomonas species) that usually attack the young canna leaves and flowers while they are still curled in the buds. The bacteria can spread from the leaves and flowers into the stems, causing plant death. Some of the infected tissue may exude a sticky ooze filled with bacteria. The bacteria are spread by splashing water and rain, and by direct contact with equipment, hands, and insects. Wet conditions enhance the spread of the disease. Bud rot survives through the winter in diseased rhizomes, contaminated soil, and infected plant debris to reinfect young plants the following spring.

Solution
There are no effective chemical controls for this disease. In order to control bud rot, it is important to reduce excess moisture around the plants. Water in the morning so the foliage will dry out during the day. Try to avoid wetting the foliage. Space plants far enough apart to allow good air circulation. Pick off infected leaves and flowers. Remove severely diseased plants and the soil immediately surrounding them. Clean up plant debris. Plant only healthy plants and rhizomes. For information on choosing healthy plants, see Choosing Plants.

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