Rose Rosette Disease is a lethal viral disease caused by Rose Rosette Virus (RRV) that affects many species of roses, including cultivated roses. The purpose of this project is to elucidate virus-vector-host dynamics among a collection of cultivated roses. These dynamics were studied at the Norfolk Botanical Garden’s rose garden and considered the geographic clustering of diseased roses, genetic relatedness of viral strains, and potential for asymptomatic roses to carry the virus. Kernel Density and Time-Enabled Kernel Density analysis indicated that disease clusters do not appear to spread from one focal point. Rather, there were complex movements and introductions of the virus into and around the garden. Three genetic isolates of RRV were identified in diseased roses, all of which have also been identified in Rosa multiflora in natural areas throughout Hampton Roads. A cultivated rose trait database was also created using several Machine Learning models, trained against documents found in the United States Patent and Trade Office. The model contains 14 traits and identifiers for 94 patented rose cultivars. Variation in the traits was compared between diseased and healthy cultivars at the Norfolk Botanical Garden to evaluate links between traits and susceptibility to RRV. Of the traits analyzed, roses with RRD tend to have red-pigmented flowers and are shorter in habit than roses that have not gotten RRD. The trait database and associated analyses provide a framework for inclusion of additional traits and cultivars, as well as potential linkages between traits and RRD that will be useful for further understanding of RRV dynamics by researchers, breeders, and growers.

Infection Relationships of Rose Rosette Disease in a Cultivated Collection
Ray Volkin

