part 3 Flashcards
what are the important stages of an infectious disease?
(truc: I-P-I-GRO-DIS)
Inoculation/incubation
* Penetration
* Infection (host recognition; invasion
and colonization)
* Growth and reproduction
* Dissemination
how is named The pathogen or any part of it that land or brought into contact with the plant is able to cause infection
the inoculum
t-f: primary inoculum is the more abundant
true
types of inoculum:
Primary inoculum:
Primary infections
Secondary inoculum:
Secondary infections:
what are the sources of inoculum
- Plant debris
- Soil in the field where the crop is grown
- Seeds, transplants, tubers or other plant material to
be planted in the field - Sources outside the field: neighbouring plants or
fields - Alternate hosts or perennial weeds
what are the names of natural openings by wich disease (microbe) penetrate?
- 2) Penetration:
Through natural openings - Stomata:
- Lenticels;
- Hydathode
t-f : only successfull infection will produce symptoms?
true
name of : The state in which a host is infected with a
pathogen but does not show any symptoms
name of : The time interval between inoculation and the
appearance of disease symptoms
Latent infection : The state in which a host is infected with a
pathogen but does not show any symptoms
Incubation period : The time interval between inoculation and the
appearance of disease symptoms
what stage is this?The pathogen will grow and multiply within the infected
host.
growth and reproduction
Viruses -fungi–Nematodes – bacteria
produce spores
replicate in the host cell
reproduce within infected tissues
reproduce by means of eggs
Fungi – produce spores
Viruses – replicate in the host cell
Bacteria:- reproduce within infected tissues
Nematodes – reproduce by means of eggs
how are diseminated the pathogens?
by air and dust
By water :
By Insects,
By Seed and Transplanting process :
By human:
what are the three components of the disease triangle?
environment, host and pathogen
what are the host variability factors:
Age :
Tolerance:
Plant growth system :
what are the pathogen variability factors
race or strain : more virulent or less virulent
Abundance : small or large numbers of the pathogen
State : dormant state, or require of a film of water, or require a vector
t-f:Disease development require short term favorable environmental
conditions
false they require long term
