Transcript High Consequence Plant Pathogens for Montana

High Consequence Plant
Pathogens for Montana
Nina Zidack
Plant Disease Diagnostics
Montana State University
High Consequence Pest List for the
Great Plains
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Karnal bunt
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Blast
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Dwarf bunt
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Seed gall nematode
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Head Scab
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Cereal Cyst Nematode (Riesselman)
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Flag smut (Riesselman added)
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Potato wart
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Late Blight
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Golden nematode
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Columbia root knot nematode
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Potato rot nematode
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Potato mop top
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Potato virus Y
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Phytoplasma Diseases
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Potato Wilt
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Corn cyst nematode
Philippine downy mildew
Late Wilt
Curvularia leaf spot
Soybean rust
Soybean cyst nematode
Soybean scab
Red leaf blotch
Soybean aphid
Soybean Dwarf Virus
Ergot
Plum pox
Sudden oak death
White Pine blister rust
Pine Wilt Nematode
Angular leaf spot
Rhizomania
Pierce's disease of grape
Potato Cyst Nematode
Pale cyst nematode
Globodera pallida
Golden Cyst Nematode
Globodera rostochiensis
Pale Cyst Nematode
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Present on the island of New Foundland,
Canada
Found in Idaho in April, 2006
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1/9000 samples since 2003
Idaho farm quarantined
Japan – Cut off all potato imports from US
Canada, Korea and Mexico
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Cut off all potato imports from Idaho
Pale Cyst Nematode
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Yield losses up to 80%
Affects tomatoes,
eggplants, and
solanaceous weeds
Poor growth, yellowing,
wilting, death of foliage
Potato Wart
Spread of Potato Wart
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Infected seed potatoes
Contaminated soil attached to tools and
machinery
Soil attached to plants and potatoes grown in
infested fields
Manure from animals fed on infected potatoes
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Spores resist digestion by animals.
Cereal Cyst Nematode
Heterodera avenae
Cereal Cyst Nematode
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Columbia River Basin
Causes up to 50% losses
First Detectors
 First Detector
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Anyone who is likely to encounter an act or
suspected act of crop bioterrorism
 Producer, Agric. Consultants, County Agents, State Dept.
Agric.
 What can we do for First Detectors?
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Training and certification
Surveillance
Registry
How does a sample progress through the
system?
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First detector encounters unusual symptoms/activity
Sample submitted to networked clinic at land-grant
institution
Clinic diagnoses problem using standardized methods
If positive for one of select agents, response system
activated
Proper channels of communication maintained
Search and Survey
for Exotic Pests
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Search Mode:
- Normal awareness
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Survey Mode:
- High
risk pest reported
- Local detection
- Distribution and spread
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Alerts posted on the NPDN, and through
Regional PDN’s.
Spatial Distribution
and Scouting
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Uniform
Random
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Factors
Time
Pest Species
Cost
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Contagious
Ability
Exotic Pests:
Where will they come from?
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Examples:
Mid West - Ralstonia solanacearum came in on
infected geranium cuttings from Nigeria and
Guatemala.
 Michigan – Emerald Ash Borer
 Mid West – Soybean Aphid
 Illinois, New York – Asian Longhorn Beetle
 Florida, California-Pink Hibiscus Mealybug
 Florida – Soybean Rust
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Monitoring for Exotics
 Be
familiar with:
 Common
 Seasonal
 Typical
pests
pest patterns
weather patterns
Monitoring for Exotics
 Be
familiar with:
 Common
 Seasonal
 Typical
pests
pest patterns
weather patterns
Karnal Bunt
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Quarantine Issues
71% of Montana
grain exported to
World Market
$700 Million Total
Crop
Potential Sabotage Point
Information Flow
Regional NPDN
Diagnostic
Laboratory
Land Grant
University
Plant Diagnostic
Laboratory
USDA:
NAPIS
APHIS
State
Department of
Agriculture
Alerts
County Extension
Farm Advisors
First Detectors
What is it?
Containment and
Eradication
Wheat – Lesion Nematode
Pratylenchus neglectus and thornei
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Dr. Alan Dyer and Wendy Lewis
Recrop production trend increasing severity
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Observations in Washington, Oregon, Idaho,
Utah, Colorado
Nematology 101
 Root lesion nematodes- Pratylenchus spp.
 Wide host range
 Extremely persistent
 Migratory endoparasites
 Symptoms in cereals
 cortical necrosis of roots
 stunting
chlorosis of lower leaves
 increased susceptibility to secondary infection
Root-lesion Nematodes
Pratylenchus neglectus & P. thornei
Spring Wheat in Soil Infested by
P. thornei at Pendleton
Machete +
aldicarb
Machete
control
27.8 bu/acre
14.3 bu/acre
 Control
 No chemical control
 No biological control
 Rotations are limited due to wide host range
 Species specific resistances are available
 Increasing populations
 No-till cropping
 Increase in soil-moisture
 Increase in recrop acerage
 Optimum nematode environment
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Montana Nematode Survey
1) Assess the prevalence and impacts of RLN on Montana’s
production system
2) Determine the possible resistances of Montana’s popular and
historical wheat varieties to Pratylenchus spp.
 Extracting Nematodes
Nematodes/ kg soil
get counts
180 statewide
samples
processing of samples
 Compare counts to damage thresholds.
 Are nematodes important?
 Identify problem areas for future study and determine
predominate species.
Preliminary Results
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Analyzed 20 samples so far (Liberty and
Choteau)
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6 samples above damage threshhold (Australian
data)
P. neglectus = 2500/kg soil
 P. thornei = 2000/kg soil
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 Resistance Screening
making inoculum
open pot
culturing
 Determine if resistances are available in current
wheat varieties.
 Determine whether nematode resistances were
present in historic wheat lines.
Sample Submission Review
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Accurate Diagnosis depends on good
sample
Samples must contain the right material:
an entire plant or several plants if practical.
Foliage diseases
Keep most roots and
soil intact if possible
Diseases may
show up on any
part of the
plant.
Check for injuries, disease
on the main stem/trunk
Dead Plants Tell no Tales
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Avoid dead plants
Choose plants which show a
range of symptoms: moderate
to severe
Packaging & Shipping
Good
Intentions
Actual Results
Packaging and Shipping blunders
Soil on foliage during
shipping creates
“diseases” that were
not there when the
sample was collected.
Packaging and Shipping blunders
Sample
Soup
Don’t add water or wrap in wet paper towels
Good Packaging
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Plastic bag to keep soil on
roots
Dry paper towels to protect
leaves from contact with
plastic bag
What’s New at the Clinic?
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Stripe Rust
Cephalosporium Stripe
Nitrogen Deficiency
Wheat Streak Mosaic Virus
Tan Spot
Physiological leaf spot
Stripe Rust - 2006
Rust Biology:
Puccinia striiformis
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Overwinters on grasses and winter wheat
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Overwintered in 2006
Infection caused by wind blown spores
Cool wet conditions (50-60ºF)
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New isolates grow at higher temperatures
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Winter Wheat and Spring Wheat (irrigated)
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Control: Resistance and/or Fungicides
Resistance:
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Winter Wheat and
Spring Wheat*
Barley- Usually
susceptible. May
escape infection due
to early maturity
2005 Stripe Rust
Evaluations
Creston, Bozeman
Winter Wheat
* http://plantsciences.montana.edu/Crops/
Fungicides:
Winter Wheat and Irrigated Spring Wheat
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If you didn’t plant a resistant variety, may have to
apply fungicide – probably have to gain 4-5 bu to
pay for the cost
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If present: Spray between the period of stem
elongation and heading – need to protect the flag
leaf. Check the preharvest interval on the label
Dryland S. Wheat? Barley?
Head Diseases
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Fusarium scab – Has caused huge yield
losses and reduced grain quality on the
northern great plains since the early 1990’s
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Favored by
rotations with corn – Yellowstone valley
 High levels of infested residue
 Sprinkler irrigation at flowering
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Cephalosporium Stripe
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Winter Wheat Disease
Residue Borne
Infects wounded roots
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Frost Heave
Rotate out of Winter
Wheat for 3 years,
reduce inoculum by
2/3
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WW-Fallow-SWFallow-WW
Sugar Beet Rhizomania
Beet Necrotic Yellow Vein Virus
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First detected 3 yrs ago
2005 – All sugarbeet
producing areas
Fungal vector –
Polymyxa betae
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Tare soils,
contaminated
equipment
30-40% of field require
rhizomania resistance
Mary Burrows
Small Grains Diseases Specialist
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Born in Fargo, ND
B.S. Moorhead State
Ph.D. Univ. of Wisconsin –
Madison
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Epidemiology of viruses and
phytoplasmas in soybeans
Master Gardener
Post Doc – USDA/ARS
Cornell
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Aphid genetics in barley yellow
dwarf transmission