Rose Rosette Disease (RRD)

Rose Rosette Disease is in Texas but currently not in Houston. This blog entry will provide a brief overview of the disease along with links to valuable resources for the green industry.

RRD Overview:

  • Rose Rosette Disease (RRD) has been identified in the Dallas – Ft. Worth area, but has not been confirmed in Houston.
  • RRD is caused by a virus (Rose Rosette Virus-RRV) that is transmitted by the eriophyid mite, Phyllocoptes fructiphylus.
  • RRD was initially identified in the US in 1941 – spread of the disease in the US is linked to Rosa multiflora that was introduced from Japan in 1866.
  • Symptoms are variable depending on the species or cultivar affected.
  • Recognizable symptoms
    • Rapid elongation of new shoots

      Elongation of new shoots.

      Elongation of new shoots.

    • Development of witches’ brooms or clustering of small branches
    • Leaves in the witches’ broom are small, distorted, and may have red pigmentation (red pigmentation may not be consistent on all roses

      Witches' broom showing distorted foliage with red pigmentation

      Witches’ broom with distorted foliage and red pigmentation

    • Develop excessive thorns that are usually soft and pliable, may be red or green that may later stiffen

      Stem showing excessive thorniness.

      Stem showing excessive thorniness.

    • Shortening of internodes
  • No effective control is available for RRD
  • Miticides registered for control of eriophyid mites can be applied in order to reduce the vector population
  • Disease management
    • Infected plants including roots must be removed. Diseased plants should be bagged and removed from the site so that the pathogen is not spread to healthy plants.

Additional resources on RRD

If you think you have a suspect rose with RRD please feel free to contact Texas A&M AgriLife Extension Harris County office at 281-855-5600.

 

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