Download Topic #4: Infectious Diseases

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Principles for Studying Infectious Diseases
(Edmonds p. 185-197)
I.
Define
A.
B.
C.
II.
Infection
1.
Parasite
2.
Host
3.
Infection
Microbial parasites
1.
Fungi
2.
Bacteria
3.
Phytoplasmas
4.
Viruses
Infectious disease
Disease complex specific to infectious disease.
A.
Components of disease complex (disease triangle).
1.
Diseased host(s).
a)
Susceptible species:
b)
Symptoms:
(i)
Necrotic -
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INT256 - Tree Pests and Disease: Infectious Disease page
c)
2.
3.
(ii)
Hypoplastic -
(iii)
Hyperplastic -
Diseased functions:
Pathogen(s):
a)
Name(s).
b)
Signs.
Environment where disease occurs.
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INT256 - Tree Pests and Disease: Infectious Disease page
III.
The Pathogen Cycle (Disease Cycle).
A.
Latent period.
1.
Infection period a)
Inoculation -
b)
Penetration.
c)
Establishment -
2.
Incubation period – colonization
3.
Symptom expression -
B.
Infectious period -
C.
Dissemination.
D.
Virulence (pathogenicity) of microorganisms.
E.
Tree Resistance
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INT256 - Tree Pests and Disease: Infectious Disease page
IV.
V.
Koch's postulates - establish if an organism is a pathogen.
A.
Isolate from diseased tissue only.
B.
Inoculate.
C.
Symptoms.
D.
Re-isolate.
Control
A.
Pathogen population dynamics
B.
Options
1.
Silvicultural -
2.
Biological -
3.
Breeding -
4.
Legal -
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INT256 - Tree Pests and Disease: Infectious Disease page
C.
VI.
5.
Chemical -
6.
Mechanical - Sanitation -
7.
Do nothing
HMP: Strategies
Associations Among Organisms - Symbiosis.
A.
Interactions involving two species.
1.
2.
B.
Parasitic a)
Biotrophic -
b)
Necrotrophic -
Saprophytic -
Balance of interaction 1.
Mutualistic
2.
Commensalistic.
3.
Pathogenic.
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INT256 - Tree Pests and Disease: Infectious Disease page
C.
VII.
Facultative or obligate.
1.
Facultative
2.
Obligate -
Terminology.
Biological control
Biotrophic
Breeding
Chemical Control
Commensalistic
Disease Cycle
Disease Triangle (Pyramid)
Dissemination
Establishment
Etiology
Facultative
Hyperplastic
Hypertrophic
Hypoplastic
Incubation period
Infection period
Infectious period
Inoculation
Inoculum
IPM
Koch's postulates
Latent period
Legal Control
Mechanical Control
Mutualistic
Necrotic
Necrotrophic
Obligate
Parasitic
Pathogen Cycle
Pathogenicity
Penetration
Quarantines
Resistance
Saprophytic
Signs
Silvicultural control
Susceptible
Symbiosis
Symptoms
Vector.
Virulence
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