For the original location of this thread, Texas, I would expect that the common virus PNRSV would be mainly in the roots during much of the growing season sinch the rose immune system against PNRSV works better at higher temperatures. However, I feel that it is worth pointing out that in cooler climates the reports of little effect on Sombreuil from hot summer rose growers may not apply (I say "may not" because it is possible that the early Sombreuil infection which has been passed down through the years was caused by a very mild strain of PNRSV.) http://home.roadrunner.com/~kuska/high_temperature_effect_on_pnrsv.htm One must also consider the possibility that this is a different virus than PNRSV or a mixed virus infection. For those of you that have seen an infected Sombreuil in climates similar to Texas, did your leaves look like these? Here is a link that might be useful: my temperature effect scientific discussion

mad_gallica -- 'Rose de Rescht' is available clean, but not due to our heat therapy. We got it from Heirloom, who apparently imported a clean one from Europe. We indexed it here and found it clean. true-blue -- I've heard people make claims for resistance to fungal diseases and other "miracle cures," but I have no reason to believe any of them. Removing the viruses that cause mosaic will alleviate any symptoms those viruses may cause, which may include fewer, smaller flowers, shorter stems, less longevity, less cold-hardiness, etc. And in at least some varieties that are said to have "declined," it seems to help reverse that. But no, I'm not aware of (nor would I expect) other major benefits. I'm sure by "indexing," you mean the heat therapy process. Actually, indexing follows therapy -- it is the series of tests done to demonstrate freedom from the viruses, after we've removed them.

The following was stated: "Newer PCR methods and other "modern" methods have NEVER ONCE shown a plant that tested clean by other methods actually to be infected with mosaic. This is assuming the tester did so under the proper conditions; comparing ELISA to PCR in the heat of summer might show a difference, but no qualified ELISA user would be so stupid as to do such a test. That's rather like demanding that we compare making ice cream in a freezer vs. an oven, and anyone who has not tried it in the oven is an idiot. The poster of such ideas seems to think that the actual researchers are mindless fools." The following is the abstract of a 2007 M.S. Thesis "This study was carried out to detect PNRSV on rose in Şanlıurfa province and its districts in 2005. Sampling was made in May. Samples were collected from public gardens. 19 samples expressing virus diseases were tested for PNRSV by ELISA and RT-PCR. The diseases incidence, as percentage of total samples for PNRSV, was found 21.05% by ELISA and 31.57 % by RT-PCR. PNRSV was determined as a new virus on rose in this region." H.Kuska comment. The average high in May is 83,8 deg F, the average low is 60.4. So of the 19 samples that exhibited virus symptoms Elsia reported that 4 were infected by PNRSV while PCR found that 6 were infected by PNRSV. The fact that there were 2 samples that were found to be PNRSV free with ELSIA but positive with PCR is consistent with studies with other plants that also showed that PCR can detect viruses below the ELSIA detection detection limit (see my web page on viruses returning to heat treated plants). A Master's Thesis is conducted under the supervision of a faculty member. ----------------------------------------- My link also included a quote (with link to a Davis document: "Occasionally, disease may not be detected in only one growing season, so nurseries and growers are cautioned to inspect their plants carefully prior to propagation." Please notice that this does NOT say something like: it is a theoretical possibility but has never happened. It states OCCASIONALLY it does happen. After you read that please go back and read what was published by Deborah M. Mathews, Ph.D., Author's affiliation: Assistant Cooperative Extension Specialist/Plant Pathologist, Department of Plant Pathology and Microbiology University of California, Riverside, Riverside, CA. about the detection of viruses in plants in general. http://ucanr.org/sites/UCNFA/files/62197.pdf -------------------------------------------------- Here is a link that might be useful: link for Thesis abstract

Henry, I've talked with Alma and her major professor about her thesis. It's one of those written as chapters suitable for publication. Both told me that the two (of four total) that deal with RRD (then) are the two published in Weed Science with several co-authors. Can your library access Weed Science? If not, let me know. Cutting off an infected cane HAS to be done before the virus moves down into the roots (assuming stem meristem infection) and back out. I've saved several roses from different classes in my yard by catching the problem when only a single leaf node (or three on one side of the cane) were infected in fall. I saved an American Pillar in spring when it was out on a cane about ten feet from the roots. I've never saved a HT, and I've only seen RRD on HTs in spring. That may have something to do with the transmission times in fall to late fall. The one thing that (I don't think) has been addressed is what it is about RRD that ultimately kills the host rose. Epstein and Hill reported a lack of sugar to starch conversion in long infected canes. The odd thing that I watched this year was that some roses I've watched for four years finally got down to scrawney, skinny leaves often with PM and then they died in May (which was not a time of drought or too much rain- just really nice weather.) We know from Glen Viehmeyer and Percy Wright that both saw RRD overwinter in the colder parts of Canada. I don't think we know much about temperature and the whole batch of EMARviruses.