Plum Pox Virus in Canada Blake Ferguson Canadian Food Inspection Agency
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Transcript of Plum Pox Virus in Canada Blake Ferguson Canadian Food Inspection Agency
Plum Pox Virus in Canada
Blake FergusonCanadian Food Inspection Agency
Plum Pox Virus in Canada
Blake FergusonCanadian Food Inspection Agency
Plum Pox VirusPlum Pox Virus
• Plum Pox Virus (PPV) is a virus that infects plants in the genus Prunus - plums, peaches, apricots etc.
• It causes a disease called plum pox or sharka.
• Plum Pox is the most serious disease of stone fruits in Europe.
• The virus has several strains : D, M, C, W and EA strains.
• Plum Pox Virus (PPV) is a virus that infects plants in the genus Prunus - plums, peaches, apricots etc.
• It causes a disease called plum pox or sharka.
• Plum Pox is the most serious disease of stone fruits in Europe.
• The virus has several strains : D, M, C, W and EA strains.
Distribution in the WorldDistribution in the World
• First found in Bulgaria around 1917
• Now present in most European countries– widespread in central & eastern Europe– recently reported in Mediterranean countries– sporadic reports in northern Europe
• Also in Egypt, India, Syria, Turkey, Argentina & Chile
• 1999 - Pennsylvania, USA, strain D
• 2000 – Canada, strain D
• First found in Bulgaria around 1917
• Now present in most European countries– widespread in central & eastern Europe– recently reported in Mediterranean countries– sporadic reports in northern Europe
• Also in Egypt, India, Syria, Turkey, Argentina & Chile
• 1999 - Pennsylvania, USA, strain D
• 2000 – Canada, strain D
BackgroundBackground
• Plum Pox Virus (Sharka)
• Decrease yield & fruit quality
• Transmitted via aphids or propagation
• Transmissibility and host range vary by strain
• Severe economic impact
• Plum Pox Virus (Sharka)
• Decrease yield & fruit quality
• Transmitted via aphids or propagation
• Transmissibility and host range vary by strain
• Severe economic impact
Host RangeHost Range
• Hosts are mainly in the genus Prunus
• Both fruit stock and ornamental plants may be infected
• PPV affects plums, peaches, nectarines, almonds, cherries and apricots
• Wild Prunus species are also hosts
• Some herbaceous weeds can be infected
• Hosts are mainly in the genus Prunus
• Both fruit stock and ornamental plants may be infected
• PPV affects plums, peaches, nectarines, almonds, cherries and apricots
• Wild Prunus species are also hosts
• Some herbaceous weeds can be infected
Canada’s Commercial Production ofPPV-D susceptible stone-fruit
• Ontario 77% • British Columbia 21%• Nova Scotia 1.1%• Quebec 0.6%
Canada’s Commercial Production ofPPV-D susceptible stone-fruit
• Ontario 77% • British Columbia 21%• Nova Scotia 1.1%• Quebec 0.6%
Stone Fruit Production in CanadaStone Fruit Production in Canada
PPV survey in Canada2005
PPV survey in Canada2005
Province Samples (orchard sampling only)
Quebec no survey
Nova Scotia 5,097
British Columbia no survey
Ontario 1,005,428
Total 1,010,525
Province Samples (orchard sampling only)
Quebec no survey
Nova Scotia 5,097
British Columbia no survey
Ontario 1,005,428
Total 1,010,525
(2003)
(2004)
24 Positives on 19 Properties(2 properties not shown on map)
= 2004 Survey
= 2005 Survey= Positive Samples
St. Catharines
Total Ontario Samples CollectedTotal Ontario Samples Collected
100,914 63,03774,080
75,998
247,227
66,226
341,800
98,615
481,885
103,223
938,199
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
2000 2001 2002 2003 2004 2005
AGRICORP
CFIA
100,914 63,03774,080
75,998
247,227
66,226
341,800
98,615
481,885
103,223
938,199
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
2000 2001 2002 2003 2004 2005
AGRICORP
CFIA
1,041,4421,041,442
Positive Blocks - OntarioPositive Blocks - Ontario
246
152
59
133
82
149
86
161
141
65
103
0
50
100
150
200
250
300
350
2000 2001 2002 2003 2004 2005
Initial Positive Blocks
New Positive Blocks
Previously PositiveBlocks
246
152
59
133
82
149
86
161
141
65
103
0
50
100
150
200
250
300
350
2000 2001 2002 2003 2004 2005
Initial Positive Blocks
New Positive Blocks
Previously PositiveBlocks
% infested blocks
2000: 246/5121 4.80 %
2001: 211/6125 3.44 %
2002: 215/7474 2.88 %
2003: 235/7911 2.97 %
2004: 302/8158 3.70 %
2005: 168/7293 2.30%
% infested blocks
2000: 246/5121 4.80 %
2001: 211/6125 3.44 %
2002: 215/7474 2.88 %
2003: 235/7911 2.97 %
2004: 302/8158 3.70 %
2005: 168/7293 2.30%
65
103
0
20
40
60
80
100
120
140
160
180
2005
Previously Positive Blocks New Positive Blocks
65
103
0
20
40
60
80
100
120
140
160
180
2005
Previously Positive Blocks New Positive Blocks
Positive Blocks - OntarioPositive Blocks - Ontario
59
44
0
25
50
75
100
125
2005
Previous suspects
Previous negatives
Detection Survey Works & PPV Infection
0
50
100
150
200
250
300
350
2000 2001 2002 2003 2004 2005
Nu
mb
er o
f B
lock
s In
fect
ed
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
2,000
Nu
mb
er o
f T
rees
In
fect
ed
Total Infected Blocks Total Infected Trees
100914137117
323225
408026
598108
1,041,422
Number of Samples Collected
As of October 19, 2005
Total positive treesTotal positive blocks
Number of samples collected
Aphid transmission of PPVAphid transmission of PPV
2004 evidence– Volunteer seedlings found to be infected– Newly planted blocks propagated from PPV-tested
budwood have been found to contain infected trees– Research indicates peach to peach transmission rates as
high as 22% using 50 Myzus persicae aphids per plant
2005 evidence– 5 residential trees grown from seed were found positive– 103 existing orchard blocks becoming positive after 4-5
years of negative testing.
2004 evidence– Volunteer seedlings found to be infected– Newly planted blocks propagated from PPV-tested
budwood have been found to contain infected trees– Research indicates peach to peach transmission rates as
high as 22% using 50 Myzus persicae aphids per plant
2005 evidence– 5 residential trees grown from seed were found positive– 103 existing orchard blocks becoming positive after 4-5
years of negative testing.
Niagara Repeat Positive BlocksNiagara Repeat Positive Blocks
Year New Positive Blocks By Year
Repeat Positive Blocks*
% of repeat positive blocks
2000 177 122 68.9 %
2001 49 33 67.3 %
2002 79 41 51.9 %
2003 71 37 52.1 %
2004 143 32 22.4 %
Total** 519 265
51.1 %
Year New Positive Blocks By Year
Repeat Positive Blocks*
% of repeat positive blocks
2000 177 122 68.9 %
2001 49 33 67.3 %
2002 79 41 51.9 %
2003 71 37 52.1 %
2004 143 32 22.4 %
Total** 519 265
51.1 %
* In at least one subsequent year.
**51% of positive blocks are repeat positives in subsequent years.
* In at least one subsequent year.
**51% of positive blocks are repeat positives in subsequent years.
Current challengesCurrent challenges
• Continuing discovery of newly positive blocks
• Availability of tested/certified replacement trees
• Clearer data needed on aphid spread of PPV
• Resistance of growers to mandatory block removals
• Need to consider buffers but – logistical difficulties
– industry structure considerations
– neighbour effect
• Continuing discovery of newly positive blocks
• Availability of tested/certified replacement trees
• Clearer data needed on aphid spread of PPV
• Resistance of growers to mandatory block removals
• Need to consider buffers but – logistical difficulties
– industry structure considerations
– neighbour effect