Transcript Plum Pox Virus

Plum Pox Virus
Ellis, McKellar, and Hodges. December 2006.
NPDN Publication No. 0004
Plum Pox Virus
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Introduction
Symptoms
Hosts
Transmission
Detection
Control
Photo: Biologische Bundesanstalt
Archives, Germany
http://www.ipmimages.org
Introduction
• Originals observations of the disease
were made by plum growers in Bulgaria in
the mid 1910s.
• In Europe the virus is known commonly
as “Sharka.”
• 1999 – PPV detected in Pennsylvania
• 2000- Ontario, and Nova Scotia
• 2006 – Confirmed in New York and
Michigan
Photo: Biologische Bundesanstalt
Archives, Germany
http://www.ipmimages.org
Map provided by EPPO (European and Mediterranean Plant Protection Organization)
http://www.eppo.org/QUARANTINE/virus/Plum_pox_virus/PPV000_map.htm
Map Source:
Canadian Food
Inspection Agency
http://www.inspection
.gc.ca/english/sci/sur
v/2003maps/ppvonqz
2003e.shtml
Confirmed Locations of PPV in the United States
Introduction
• PPV does not kill trees but causes yield losses and
reduces the marketability of fruit.
• In Europe, reported losses of 80-100% in susceptible
cultivars
• PPV belongs to the genus Potyvirus in the family
Potyviridae
• PPV characterized into 4 serological strains (M,D, EA,
and C)
• PPV-D most common strain in Western Europe and is
found in US and Canada
Photo: Biologische Bundesanstalt
Archives, Germany
http://www.ipmimages.org
Symptoms
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PPV symptoms may appear on leaves,
fruits, flowers, and seeds.
Infections are not transmitted through fruit.
Infections without symptoms may occur.
May show uneven distribution within the tree
Severity of symptoms depends upon:
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Plant species
Cultivar
PPV strain
Season
Temperature
Location
Varied host
susceptibility by
PPV strain.
Photos: Biologische Bundesanstalt
Archives, Germany
http://www.ipmimages.org
• Leaves
Symptoms
– Yellowing and browning
ring patterns, bands, or
blotches
• Fruit
– Yellowing and browning
ring patterns, bands, or
blotches
– Misshapen or deformed
• Flowers
– Streaking on the petals
– Pigmented ring patterns
Photo: Biologische Bundesanstalt
Archives, Germany
http://www.ipmimages.org
Hosts
• Natural hosts of PPV are restricted to the genus Prunus
but has been artificially introduced to others
– Peaches
– Plum
– Apricots
– Nectarines
– Almonds
– Sweet cherry
– Tart cherry
– Some
Terry Spivey, USDA
ornamental and Photo:
Forest Service
http://www.ipmimages.org
wild native
Prunus species
Photo: Peggy Greb, USDA
Agricultural Research Service
http://www.ipmimages.org
Transmission
• Introduction to new regions through
propagative materials and distribution of
contaminated materials
– Live nursery stock
– Grafts
– Budwood
Photo: Carroll E. Younce, USDA
Agricultural Research Service
http://www.ipmimages.org
Transmission
• Once in a region, spread occurs by aphid
transmission
• Efficiency of transmission determined by:
– Virus strain
– Host cultivars,
– Age of host cultivars
– Aphid species
– Time of year
Photographer: Whitney Cranshaw,
Colorado State University
http://www.ipmimages.org
Myzus persicae
Transmission
• PPV has been transmitted
by at least 20 aphid
species
• Most important vectors in
Pennsylvania:
– Myzus persicae
– Aphis spiraecola
• Transmitted by transient
(moving through orchard)
and colonizing (staying in
the orchard) aphids
Myzus persicae
Photo: Scott Bauer, USDA
Agricultural Research Service
http://www.ipmimages.org
Transmission
• Piercing-sucking mouthpart probes vascular
tissue of plants while feeding, PPV sticks to
the food canal
• Injected into another plant as aphid feeds
• PPV can be acquired by probes as brief as
30 seconds
• PPV transmitted usually within 1 hour
• Most aphids cannot transmit
virus over 120 meters from
initial source plant
Photographer: Whitney Cranshaw,
Colorado State University
http://www.ipmimages.org
Detection
• PPV physical symptoms may not appear for 3 years after
initial infection if at all.
• Serological and molecular tests used to detect virus
before symptoms occur – ELISA.
• Diagnostic hosts, such as Chenopodium foetidum, can
be used to detect PPV by mechanical inoculation from
suspect hosts
• Woody indicator plants are also useful for detecting the
virus by chip budding to hosts. This method allows for
the differentiation of the M and D strains based on
symptoms.
Photo: Scott Bauer, USDA
Agricultural Research Service
http://www.ipmimages.org
Chenopodium foetidum
Detection
• More sensitive and
accurate detection of PPV
possible through RT-PCR
(reverse transcription
polymerase chain
reaction) technology
• Currently, rapid detection
of PPV with RT-PCR is
achieved with Real-Time
PCR
• PCR can make diagnosis
with low concentration of
the virus
• About 5000 times more
Real-time PCR utilized for
sensitive than ELISA
rapid PPV detection. (Photo
Dawn Dailey-O’brien, Cornell
University)
RT-PCR assay. Lane 1 is
healthy;Lanes 2-4 are
PPV infected.
Courtesy L.Levy.
Reproduced from L. Levy,
V. D. Damsteegt, R.
Scorza, and M.
Kölber, Plum Pox
Potyvirus Disease of
Stone Fruits, 2000,
APSnet feature,
http://www.apsnet.org/onl
ine/feature/PlumPox/Top.
html
Control
• No chemical controls available to prevent,
eliminate, or cure PPV in the field.
• If you suspect PPV,
– contact your local cooperative extension agent
http://www.csrees.usda.gov/qlinks/partners/sta
te_partners.html
– NPDN lab
http://www.npdn.org
Photo: John Hammond, USDA
Agricultural Research Service,
http://www.ipmimages.org
Control
• Exclusion and Quarantine –
• In order to prevent the introduction of the virus
into new areas of the US…
– All plant material should be carefully regulated and
inspected.
– All imported host plants should be tested for plant
pathogens.
– Growers should purchase only certified virus-free
planting stock.
• Exercise extreme caution when purchasing
plants!
• Restrictions protect Growers!
The Plant Disease Diagnostic Clinic,
Cornell University (2001)
Control
• Eradication – Control spread by eliminating infected trees
as quickly as possible.
– Suspected trees must be sampled multiple
times due to the uneven distribution of PPV
within a plant.
– Infected trees should be bulldozed or cut and
sucker shoots eradicated with herbicides.
The Plant Disease Diagnostic Clinic,
Cornell University (2001)
Photo: Robert F. Wittwer,
Oklahoma State University
http://www.ipmimages.org
Control
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Insect Control –
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Insecticides do not effectively control aphid
populations.
Only one infected aphid is needed to spread PPV.
Positive trees should be destroyed.
Insecticides may be applied to aphids prior to tree
destruction in order to possibly reduce the
number of infected areas in geographic area.
Photographer: Whitney Cranshaw,
Colorado State University
http://www.ipmimages.org
Control
• Plant Breeding and Genetic
Engineering
– Breeding plant resistance
from naturally occurring
genes in fruit trees.
– Genetic engineering may
allow scientists to enhance
resistance.
The Plant Disease Diagnostic Clinic,
Cornell University (2001)
Photo Courtesy R. Scorza. Reproduced from L. Levy, V. D.
Damsteegt, R. Scorza, and M. Kölber, Plum Pox Potyvirus
Disease of Stone Fruits, 2000, APSnet feature,
http://www.apsnet.org/online/feature/PlumPox/Top.html
Transgenic C5 Plum resistant
to PPV contains the PPV
Coat Protein (Photo Scott Bauer,
USDA-ARS,
http://www.ars.usda.gov/is/graphics/ph
otos/sep01/k8891-19.htm)
References
• Levy, L. Damsteegt, V., Scorza, R., and Kolber, M. 2000.
Plum pox – potyvirus disease of stone fruits. The American
Phytopathological Society.
http://www.apsnet.org/online/feature/PlumPox/Top.html
• Levy, L. 2001. ELISA laboratory protocols for the plum pox
virus national surveillance program. APHIS-USDA.
http://www.aphis.usda.gov/ppq/ep/plumpox/protocols.pdf
• APHIS-USDA. Emergency and Domestic Programs – Plum
Pox.
http://www.aphis.usda.gov/ppq/ep/plumpox/background.html
• Plant Disease Diagnostic Clinic. 2001. Plum Pox Virus
Factsheet. Cornell University.
http://plantclinic.cornell.edu/FactSheets/plumpoxvirus/plumpo
x.htm
Additional Websites:
• A list of federal, state, university,
international, and organization websites
about Plum Pox Virus can be found at the
USDA, National Agricultural Library,
National Invasive Species Information
Center
http://www.invasivespeciesinfo.gov/mic
robes/plumpox.shtml
Acknowledgments
Editorial Review
• Dr. Ruth Welliver, Pennsylvania
Department of Agriculture
• Karen Snover-Clift, Cornell University,
NEPDN Associate Director
Background photo: Carroll E. Younce,
USDA Agricultural Research Service
http://www.ipmimages.org
Authors
• Amanda M. Ellis, [email protected],
University of Florida, SPDN
• Mary M. McKellar, [email protected]
Cornell University, NEPDN Training Coordinator
• Amanda C. Hodges, Ph.D., [email protected]
University of Florida, SPDN Assistant Director
Publication Details
• This publication can be used for non-profit,
educational use only purposes. Photographers
retain copyright to photographs or other images
contained in this publication as cited. This material
was developed as a topic-based training module for
NPDN First Detector Training. Authors and the
website should be properly cited. Images or
photographs should also be properly cited and
credited to the original source.
• Publication Number: 0004
• Publication Date: December 2006