Additional information about BCRV with pictures. "A survey of several isolates collected from blackberry and rose across the United States revealed minimal diversity between isolates, although the New World population of the virus is very different from the only European isolate sequenced (87). The virus is widespread in the eastern part of the United States, especially among wild roses where the vast majority of the samples tested were infected with the virus. Given that there are several reports of thrips and bees transmitting ilarviruses as a function of moving pollen from infected to healthy plants (11,105), the wild rose population may be a significant reservoir of the virus. As seed is another means of transmission of ilarviruses, several hundred seeds from rose, blackberry, and herbaceous plants were tested, and the virus was found to be transmitted at high rates (87). The virus was found to be the second most widespread virus in BYVD-affected plants and has been identified in Arkansas, Florida, North and South Carolina, Missouri, Oklahoma, and Oregon (I. E. Tzanetakis, S.W. Scott, B. Poudel, unpublished). Title: "Viruses and Virus Diseases of Rubus" Authors: "Robert R. Martin (1), Stuart MacFarlane (2), Sead Sabanadzovic(3), Diego Quito(4), Bindu Poudel(5), and Ioannis E. Tzanetakis(5)" Authors affiliation: (1) USDA-ARS Norticultural Crops Research Laboratory, Corvallis, OR. (2) The James Hutton Institute, Invergowrie, Dundee, Scotland. (3) Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Mississippi State. (4) Centro de Investgaciones Biotecnologicas del Ecuador, Guayaquil. (5) Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville. Published in: Plant Disease, volumn 97, pages 168-182, ( 2013). Here is a link that might be useful: link to full paper with above quote

Taoseeker stated: "It would be interesting to compare a few old varieties with the heat treated ones." I am not sure if you are refering to what what I think you are. If you are interested in whether a virused but then heat treated plant does better or worse than one of the same variety that was never virused, this is my response. Plants are very complex, it is possible that the virus and / or the heat treatment may have affected other mechanisms (could be positive or negative). There are many types of examples but since a very recent (2009) example of the "expression of heat stress proteins" has been studied in a rose, I will present that example. The actual research paper is very technical. The paper is at the following link: http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=6203748 Rather than looking at the specific details most readers would probably benefit more from the following summary of the field: http://www.cspp.cn/Annual2009/upload/pub09.pdf Please notice the statement: "It is known that rapid heat hardening can be elicited by a brief exposure of cells to sub-lethal high temperature, which in turn provides protection from subsequent and more severe temperature." This does not "prove" that heat treated roses will have better heat resistance. Maybe a longer term of high temperature will result in other effects (positive or negative). I am presenting this to indicate that one cannot assume that other variables are being held constant. It is possible that effects may not show up till years later. Some "cured" polio victims are now finding that many years later problems related to the polio are appearing. -------------------------- The effects of a virus infection can be very unexpected. The following link discusses the observed effect of a virus on aphid population (not done on roses): http://www.springerlink.com/content/uw13564v21223876/ I have posted several times about my experince with a virused Culbert Grant from Pickering. Up to then my best Climber was Illusion. This new Culbert Grant bloomed and grew much better than Illusion all summer. I was very excited. That winter I received a letter from Pickering that it was virused and that they were pulling it off the market. That spring it was dead. Scientists at Cornell University surveyed approximately 2500 roses by visible assessment. They found that 166 had virus symptons: http://www.actahort.org/books/234/234_53.htm From the abstract, it does not appear that anything unusual was observed, but from the full paper a number of unexpected results were reported such as: "Total flower cut weight and total number of flower cuts with nonsymptomatic foliage was greater from PNRSV (severe) inoculated rose plants than from healthy control plants. The data revealed also that PNRSV (severe) and ApMV (severe) inoculated plants outyielded the PNRSV (mild) inoculated plants, which in turn outyielded the healthy tissue inoculated plants. These results were unexpected since reduced yields would be anticipated from virus infections." They then discuss some "maybes. one of these is: "Another speculation is that the initial stage of viral infection stimulates host metabolism by competing and utilizing the host ribonucleic acid polymerases for ita viral replication." i.e. The virus infection may be causing the rose to grow better. ----------------------------------------------- The following non rose paper may be of interest: http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=6203748 Explanation of the sympols: (VT) I assume that (VT) means heat treated since I found this using heat treatment as a key work. The abstract is not clear. (My literature search service says the full paper can be down loaded but when I try it states that it is too new and has not been uploaded yet.) (V) is virused infected. (VTR) is virused reinfected. Just to highlight one of the observations: "V plants produced big tubers that weighed more than those from VT plants."

The following is a 2012 PDF download report from U. California, Davis which reports finding low numbers of CNRNV infections in their Prunus species collection (Cherry 4%, peach 3.2%, and plum 2.5%). Unfortunately, they do not know the countries of origin of their infected plants. "EVALUATION OF THE PHYTOSANITARY STATUS OF THE PRUNUS SPECIES IN THE NATIONAL CLONAL GERMPLASM REPOSITORY IN CALIFORNIA: SURVEY OF VIRUSES AND VIROIDS" http://sipav.org/main/jpp/index.php/jpp/article/download/2464/1141

Found this post in another thread, maybe the strain I dealt with was different from Diane's: henry_kuska 6 years ago There is no such thing as a virus named RMV. RMV is the group name for a number of viruses that infect roses. Even for a single virus in that group there are different strains that have different virilities. Also, the rose imune system has been shown to be more efective at fighting PNRSV (usually considered the most common rose virus in the U.S.) at higher temperatures than at lower temperatures. Thus, someone in a warmer climate may feel that a certain virus infection is not a big deal, but that experience probably will not apply to the same variety of rose with the same virus (and same strain) infection grown in a cooler climate. Also, since we are normally dealing with hybrids, the immune system can vary from rose variety to rose variety. When you add that it may be a different virus, a simultaneous infection with two or more types of virus, and/or an infection with a different strain of an individual virus; you see that it is risky to make general statements about what an untested rose virus infection will mean to someone else.