Is this rose mosaic virus? - Ask Extension
Hi,I have several rose bushes showing light blotches on the upperside of several leaves. There is no visible damage to the undersides and I can't see ...
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Is this rose mosaic virus? #726750
Asked September 25, 2020, 8:55 AM EDT
Hi,
I have several rose bushes showing light blotches on the upperside of several leaves. There is no visible damage to the undersides and I can't see any pests. The blotches have appeared recently and were not there earlier in the season or last year. All my roses are own-root and most were planted last year (2019).
I had assumed that this was a nutrient deficiency of some sort but a commenter in an online forum thinks it is rose mosaic. The pictures or mosaic in my books don't look quite the same, but I'm not sure.
Is this rose mosaic? I would be upset to lose these plants, but if I've somehow introduced mosaic virus to the garden I will need to triage.
Oakland County Michigan
Expert Response
This does not look like rose-rosette virus which also exhibits with extreme "witches brooming" on the terminals. https://www.canr.msu.edu/news/rose_gardeners_should_learn_the_symptoms_of_rose_rosette_virus
It could be a virus, but also a heat stress issue. I would just wait until next year to see how it leafs out and then make decisions then. If the entire plant looks like it has a virus, the only way to control it is to pull it out and get rid of the plant.
Thanks for your response!
I wasn't worried about rose-rosette virus, but rose mosaic virus (RMV).
As you say, this could be heat stress. What I've read of RMV suggests it usually manifests in the spring, which didn't happen for me. Your advice to wait until next year is good.
Thanks again.
Sorry- I was moving too fast this morning! It is possible that it is RMV but the symptoms are slightly different- with more distinctive patterning. I still would wait and see. It would be a bummer to have to take it out.
