The ARS is funding a three year study at the University of Tennessee. Objectives include trying to develop an ELISA test and studying the spread within garden conditions of a garden composed solely of a single cultivar (way out in the country where there are no rose gardens down wind). They have as RRD source plants severely infected plants of the same cultivar. I haven't heard the results of the first year, yet. ----------------- re R. rugosa. Early on, in the garden we followed at Lincoln Memorial University, there was also a plantings of many Pink Grootendorsts near a building that had been the Dairy. They did not get sick for several years as the modern roses planted immediately downwind of multiflora-rich field whose plants were at least 30%infected with RRD. At one time we found some strange swellings on the PG canes, and they made the rounds of a number of Plant Pathologists; no idea what their problem was, but it was just the swelling. Then five or six years in, a plant got two canes that were even more thorny, whose new growth spiraled, whose leaf margins were different and whose blooms were messed up badly. Now I wish I had made scans of the canes, but we were busy with other plases of following the disease as it spread. The problem with the declarations that certain roses don't get RRD is that no one has ever taken the spectrum of all roses species and planted them in different USDA zones and left them in high disease pressure areas for a five to seven year period. What I've seen this winter, when where I live is zone 7 low temperatures, is that the plants with RRD have grown through winter....at least the parts with RRD have. The uninfected canes have gone semidormant. There's so much that we don't know. Here is a link that might be useful: Rose Rosette E-book

The papers did not give the authors affiliation. From other papers by some of the authors it appears that at least some of them are located at the Department of Plant Pathology, University of Arkansas, Division of Agriculture, Fayetteville, AR, 72701, USA. and some are from USDA-ARS Horticultural Crops Research Lab. Corvallis, OR, 97330, USA. see the link below. Here is a link that might be useful: link for other work by same authors.

The following was stated: " Reducing the severity of the symptoms....so we can keep sick plants around waiting for additional vectors to find them and spread it? Balderdash" H.Kuska comment: It is my understanding that there are roses that are resistant to natural in field infection. What does this mean? Some observations may be due to the mites not recognizing the leaf surface as belonging to a rose. We do not have to worry about these spreading the infection as they were never bitten. However, what about the others that were bitten but were able to control the infection naturally? Are they going to be "Typhoid Marys" of the rose world? This appears to be a concern of the above quote. My first thought is that the "surviving rose" may have a virus concentration below the amount necessary to overcome most clean roses' natural defense system. The virus plant world is not black and white. There are plants that do not get infected by a particular virus (complete resistance). There are plants that exhibit partial resistance, and there are plants that exhibit so little resistance that the virus kills it. If we add an external chemical that boosts the immune system of a plant so that the plant does not die from the infection, are we providing the plant the opportunity to "fine tune" its immune system naturally so that it will be able to fight the virus in the future without addition application of the external chemical? The literature supports this possibility. This is called systemic acquired resistance against plant viruses. https://www.google.com/webhp?hl=en&authuser=0&gws_rd=ssl#q=systemic+acquired+resistance+against+plant+viruses&newwindow=1&hl=en&authuser=0&start=90 Can this plant that has acquired SAR pass it on to the next generation? Evidence is now being accumulated that supports the possibility of "next-generation systemic acquired resistance". http://www.plantphysiol.org/content/158/2/835.short http://scholar.google.com/scholar?hl=en&q=%22next-generation+systemic+acquired+resistance%22+against+plant+virus&btnG=&as_sdt=1%2C36&as_sdtp= https://www.google.com/webhp?hl=en&authuser=0&gws_rd=ssl#newwindow=1&hl=en&authuser=0&q=%22next-generation+systemic+acquired+resistance%22+against+plant+virus

As the following quote indicates, there was a need for improvement in rose rosette virus testing methods. "Current RT-PCR based diagnostic methods for RRV are time consuming and are inconsistent in detecting the virus from symptomatic plants. Real-time RT-qPCR assay is highly sensitive for detection of RRV, but it is expensive and requires well-equipped laboratories. Both the RT-PCR and RT-qPCR cannot be used in a field-based testing for RRV. Hence a novel probe based, isothermal reverse transcription-recombinase polymerase amplification (RT-exoRPA) assay, using primer/probe designed based on the nucleocapsid gene of the RRV has been developed. " See: http://www.sciencedirect.com/science/article/pii/S0166093416304840