Progress in establishing the rose collection

Dimitre Mollov, Kevin Ong, Maher Al Rwahnih Rose virus culture collection

USDA – Agricultural Research Service Beltsville Agricultural Research Center Beltsville, MD Acquisition and establishment of rose virus positive control collection

Overall goals: To support FPS, Texas A&M, NPDN diagnostic labs, and other rose diagnostics and research entities by providing standardized rose virus controls and virus detection methods. Increase confidence in virus detection assays. Enhances the production of clean plant material. Objectives

• Acquire rose varieties infected with known to establish rose virus collection. Whole plants will be obtained whenever possible. Clonal propagation techniques will be used to establish own-rooted rose plants if necessary. • Utilize and compare established diagnostic protocols to test infected roses before material is added to the virus collection. • Make material from the collection available to the NCPN, NPDN, and others to use as positive controls in diagnostic tests. Plan of action -- Project milestones

A. Identify and acquire roses infected with the following viruses, with as many single infections as can be identified: • Apple (ApMV), family Bromoviridae • Blackberry chlorotic ringspot virus (BCRV), family Bromoviridae • Prunus necrotic ringspot virus (PNRSV), family Bromoviridae • Rosa multiflora cryptic virus (RMCV), family • Rosa rugosa leaf distortion virus (RrLDV), family • Rose rosette (RRV), family Fimoviridae • Rose spring dwarf associated virus (RSDaV), family Luteoviridae • Rose yellow leaf virus (RoYLV), family Tombusviridae • Rose yellow mosaic virus (RoYMV), family • Rose yellow vein virus (RYVV), family • Strawberry latent ringspot virus (SLRSV), family • (TSV), family Bromoviridae B. Partner with FPS and TPDDL to screen rose cultivars for virus infection. C. Compare TEM, HTS and CMM for rose virus detection efficiency, reliability, and accuracy. D. Determine the best protocol for the screening process to ensure the most accurate virus description. E. Establish a rose virus culture collection containing virus infected curated roses. F. Initial collection of about 25 rose varieties containing rose viruses listed above will be made available and published on a public website (http://ucanr.edu/sites/ncpnrose/). Anticipated accomplishments

• Streamline detection protocols • Prioritize collection plan • Identify as many as possible single infections from the 12 prioritized viruses • Assess and add new viruses as necessary • Maintain at least two copies of each genotype Current progress

• All Pis met in Davis, CA for an initial planning meeting • Protocols and collecting priorities were discussed • FPS virus indexing field evaluation; ~10 rose varieties were identified to be shipped in Spring 2019 for virus collection inclusion • Ong and Mollov visited Weeks Roses • University of Minnesota and a rose field in Wisconsin visit • Currently the collection has 52 roses suspected to be infected with: • Rose yellow vein virus • Rosa rugosa leaf distortion virus • Rose cryptic virus • Rose yellow mosaic virus • / Prunus necrotic ringspot virus • and few others to be determined Current progress Current progress

Current progress

FPS field and laboratory Rose virus culture collection

Winter temperature controlled screenhouse

Current progress Summary

• Curated rose virus culture collection started in 2018 • USDA ARS facility has obtained necessary APHIS permits • Technology transfers/legal documents are being approved as requested • Detection protocols are selected but testing has not been initiated yet; anticipate to start summer 2019 • Currently holding 52 infected plants • Collection will be constantly improved