Rose Rosette Disease
By LandPatterns December 10th, 2013 @ 2:43
If you enjoy growing landscapes and roses in the Dallas-Fort Worth area, beware of a disease that has been prominent in the area for the past 2 years: Rose Rosette Disease.
Even among the Knockout Roses, which are widely used and are known to be quite disease free, Rose Rosette can affect a stand of Knockouts as quickly as several weeks to a couple of months. The disease does not kill the plant but deforms and stunts the growth.
The exact cause of the disease is unknown, but a virus is the most likely cause. Eriophyid mites and phytoplasma have also been linked to the disease’s development or the plant’s susceptibility.
- Eriophyid mites – Also known as bud, blister, gall and rust mites, eriophyid mites are very tiny worm shaped mites with long bodies. Able to feed deep within the plant tissues, they suck out plant juices, and transfer a substance or toxin which damages the plant. However, while they aid in the disease’s transmission via walking and the wind in longer distances, the act of the eriophyid mites feeding on the plants is unlikely to independently cause Rose Rosette Disease.
- Phytoplasma – Phytoplasma is a specialized bacteria that affect parasites of plant phloem tissues and insects that transmit diseases. Found in some symptomatic plants of Rose Rosette Disease, phytoplasma it is not present in all cases, and when present has shown improvement with antibiotic applications.
The symptoms of Rose Rosette Disease are variable on different roses, but include:
- Witches broom
- Malformed flowers and leaves
- Excessive thorniness
- Red discoloration
- Lateral shoot elongation
- Flattened stems
- Enlarged stems
As of now, there is no effective method to treat the virus on an infected plant, and the virus can be manifested as a systemic virus, where pruning out the infection is not effective. Prevention is the best option. Below are the best prevention practices:
- Remove plants exhibiting symptoms as soon as detected.
- Reduce the probability of transmission by eriophyid mites by treating adjacent plants with miticide.
- Monitor regularly for symptoms, and take swift action when symptoms appear.
- Before replanting in the same area, remove all diseased plants so as to not pass on the disease to the new plants.