Rose Rosette Disease Challenges

Home , Rosa arkansana, Rosa multiflora, Rose (symbolism)

Dr. Tom Evans, Professor of Plant Pathology Nancy Gregory, Plant Disease Diagnostician Danielle Novick, Graduate Student Terry Mhora, Graduate Student Department of Plant and Soil Sciences University of Delaware

With the Help of the entire RRD Team Disease Management

Virus has no treatment Historically the vector Disease reservoir is still was not controlled well expanding in range. with acaricides

Diseased plants must be removed as soon as possible. Goal = Resistance/tolerance to virus and better vector management Significance 2013 U.S. market for landscape roses $928 million

2014 U.S. wholesale value of container & bare-root roses $400 million

Private Consumers

Public Taxpayers Gardens

Stakeholder s

Landscape Breeders Companies

Growers

2010/2011 renovation of Cranford Rose Garden at Brooklyn Botanic Garden because of widespread RRD infection.

Consumer surveys in 2014 of 1500 consumers indicated that disease resistance is the most desired trait in new cultivars.

Survey by Brickman, landscape firm located in 33 states won’t plant more roses in areas of high RRD pressure

Southlake TX spending $500,000 to replace thousands of infected roses in medians and parks According to USDA data, roses are the most economically important ornamental plant in the U.S. Symptoms & Significance

• Abnormal reddening • Leaf and bud distortion • Increased succulence • Excessive thorniness • Shoot elongation • Blossom blight • Witches’ broom • Stunting • Dieback • Plant death Symptoms of RRD Key Problem and ‘Diagnostic’ = Symptoms (and eventual death)

RRD causes elongated rose shoots, An excessive number of thorns on leaf distortion and an unusual red or shoots is another symptom of RRD. yellow mottle of the leaves. Key Problem and ‘Diagnostic’ = Symptoms (and eventual death)

Rosetting and red shoots and leaves. Parts of plants look healthy and other parts show typical sympotms Rosa multiflora and Rose Rosette Disease

1700s: imported to North America as rootstock and ornamental and erosion control • Up to half a million seeds in a year • Spread by birds and small mammals • Seeds remain viable 20+ years • Root suckering & layering produce thickets • Repository for virus and vector of RRD • Rose rosette is NOT a good biocontrol agent for multiflora rose 1940: RRD symptoms first described in Manitoba, Canada; reported in California and Wyoming in 1941

1940s – 1960s: promoted to combat erosion, form living fence, and provide wildlife habitat; 34 million planted in WV & NC alone

1994: RRD proposed as biological control for multiflora rose

2006: multiflora infests approximately 45 million acres in eastern United States EDDMapS. 2015. Distribution of Non-Native Rose in the US The March of RRD from West to East

WA MT ND MN WI ME SD VT OR ID MI NH WY NY MA 1959 IA NE T PA IL IN OH NV NJ MD UT DE 1953 KS 1978 MO 1986 WV1996 KY VA 2001 CA 1985 1985 1941 OK TN NC 1982 AR AL AZ NM MS GA TX LA

AK FL

Large Reservoir of Virus in Large Populations of Rosa multiflora The Distribution of RRD in U.S.

Now reported in garden roses in India Aerial View of Rose Field

Block 1 Block 2 Block 3 Resistance Trial at the University of Delaware

More than 300 unique rose genotypes planted in randomized 3-block design since May 2015

All roses augmented 5 times over 2 years

Symptomatic roses confirmed for RRD with endpoint RT-PCR Mite location and detection – where do they hide? Rose Genotypes That Have Not Yet been Tested Positive for RRV and may be Resistant

Cultivar Where Assessed Comments 10037N046 TN TAMU10-69, WOB26xOB212xHomerun

10043N019 TN TAMU7-20, Sweet Chariot x M4-4, Basye Thornless parentage 10043N49 TN TAMU7-30, Sweet Chariot x M4-4, Basyes Thornless parentage 218-97-17 TN Moore, VisViolet x Magseed, rugosa parentage via Rugosa Magnifica 2-30-07 TN, DE Moore selection, Sequoia Ruby x Ginas Rose, carolina/rugosa parentage via Basyes Legacy

4-48-07 TN Moore, Show N Tell x Ginas Rose, carolina/rugosa parentage via Basyes Legacy

66-84-18 TN, DE Moore selection, Anytime x Rugosa Magnifica 88-3A TN Basye, rugosa hybrid

90-82 TN, DE Basye, carolina, rugosa/BasyeThornless parentage via 86-7 Brite Eyes Very fertile, already some families, climber, maternal parent of Sunny Knockout

FF TN Basye, carolina parentage, possibly rugosa and Basye Thornless Fru Dagmar Hastrup TN, DE Rugosa hybrid

Fuzzy Wuzzy Red TN, DE Moore, rugosa hybrid, Scarlet Moss selfed, Dortmund in parentage G02-2-1 TN, DE Sequioa Ruby x 90-82, carolina, rugosa/BasyeThornless parentage via 86-7

Hansa TN Rugosa hybrid Rose Genotypes That Have Not Yet been Tested Positive for RRV and may be Resistant Cultivar Where Assessed Comments

M4-4 TN, DE Basye Thornless parentage via WOB26

John Davis TN, DE Canadian cv, 3x, rugosa via kordesii and laxa/spinosissima via Suzanne Lafter TN, DE OGR, wichuraina in parentage

Little Buckaroo TN, DE Miniature, 3x, Rosa wichuraiana in parentage, poor fertility M4-4 TN, DE Basye Thornless parentage via WOB26

Manetti TN, DE Rootstock

Moje Hammerberg TN Rugosa parentage

Morden Centennial TN, DE Canadian, Rosa arkansana in parentage

Morden Fireglow TN, DE Canadian, Rosa arkansana in parentage

Purple Pavement TN, DE Rugosa hybrid Sorcerer TN

Star Delight TN, DE Rugosa hybrid, fertility?, Yellow Jewell x Rosa magnifica Sunny Knockout TN Parentage of Brite Eyes

Therese Bugnet TN, DE Rugosa hybrid

Winnipeg Parks TN Canadian, Parkland series,db,mpk, Rosa arkansana parentage, gd R to blackspot, pmildew,rust in Canada Wintersun TN Eleganza,HT,db,or-yel,Kordes Unreported parentage New Genotypes of Rose Confirmed RRV-Susceptible by Symptoms and Endpoint PCR Testing Sept 2018 - Delaware

Nearly Wild Lady Shallot Easy Elegance Screaming Neon Red Easy Elegance Como Park Easy Elegance Mystic Fairytale Easy Elegance Brick Red Easy Elegance High Voltage First Edition A+B Tequila Sunrise x15680-6 13FA7 Phenotyping Group Measure the strength of resistance that a rose has to the Rose Rosette Emaravirus.

{ This Or This

{ Thank You!

Danielle Novick (aka Juniper Lake)

Nicole Donofrio David Frey Brian Kunkel

Nancy Gregory Bill Bartz Rodney Dempsey

Terence Mhora Nilwala Abeysekara Vidhya Raman

Jen Olson (Oklahoma State) Francisco Ochoa Corona (Oklahoma State) The Rose Rosette Team

{

USDA National Institute of Food and Agriculture (NIFA) Specialty Crop Research Initiative project, “Combating Rose Rosette Disease: Short Term and Long Term Approaches” (2014-51181-22644/SCRI)