test 1 pt.2

Question 1

inoculum

Answer 1

any part of a pathogen that can initiate disease.

Question 2

primary inoculum

Answer 2

survival form of pathogen that causes primary infection.

Question 3

Secondary Inoculum

Answer 3

inoculum produced by pathogen and transmitted to host during the growing season.

Question 4

inoculation

Answer 4

transfer of inoculum onto the host plant.

Question 5

infection court

Answer 5

initial site of contact between pathogen and surface of host.

Question 6

Penetration

Answer 6

getting inoculum into host tissue

Question 7

direct penetration

Answer 7

through intact plant surfaces.

Question 8

indirect penetration

Answer 8

through natural openings and wounds.

Question 9

infection

Answer 9

establishment of pathogen within host.

Question 10

invasion

Answer 10

pathogen invades other plant tissue beyond initial penitration

Question 11

colonization

Answer 11

growth and reproduction of pathogen

Question 12

incubation period

Answer 12

time period from infection to appearance of symptoms.

Question 13

latent period

Answer 13

time from infection to production of secondary inoculum

Question 14

polycyclic disease

Answer 14

disease whos pathogen possesses a secondary infection cycle.

Question 15

monocyclic disease

Answer 15

lacks secondary infection cycle.

Question 16

predisposition

Answer 16

when certain environmental conditions make a plant more vulnerable to disease.

Question 17

What are the 6 stages of Disease

Answer 17

1. Primary inoculum
2. Dispersal
3. infection court
4. infection and colonization
5. secondary inocuum
6. pathogen survival

Question 18

4 main mechanisms of inoculum dispersal

Answer 18

wind, water, on plant material or by vectors.

Question 19

How can a pathogen survive if its seperated from its host?

Answer 19

it enters the survival stage

Question 20

6 environmental Factors

Answer 20

1. Temperature
2. Moisture
3. Light
4. Wind
5. Soil Nutrients
6. Soil type and pH

Question 21

Disease Management 4 parts.

Answer 21

Avoidance,Exclusion,Eradication,Protection

Question 22

Avoidance

Answer 22

Plant when or where pathogen is not present.

Question 23

Exclusion

Answer 23

Legal restrictions.

Question 24

Eradication

Answer 24

removal of pathogens from infested soil and tools, and infected seeds or plants

Question 25

Protection

Answer 25

cultural practices, chemical or biological treatments and genetic resistance.

Question 26

Five major groups of plant pathogens

Answer 26

1. Fungi 2.Bacteria 3.Nematodes 4.Viruses 5.Parasitic Seed Plants. Plus: Protozoa

Question 27

Fungi

Answer 27

Small thread like organisms composed of hyphae. | Cause 70% of plant disease, >10,000 fungus species cause plant disease.

Question 28

Bacteria

Answer 28

Small-single celled organisms with cell walls. | prokaryotes, no nucleus. 100 species cause plant disease.

Question 29

Nematodes

Answer 29

Unsegmented round worms, to small to be seen with the naked eye. 500 species attack plants.

Question 30

viruses

Answer 30

1000 species cause disease, very small particles that consist of nucleic acid and a protein sheath.

Question 31

Parasitic seed plants

Answer 31

Higher plants that produce seed, 2500 species parasitic,

Question 32

Protozoa

Answer 32

not accepted as plant pathogens, only flagellate protozoa are associated with plant disease.

Question 33

Koshes postulates (4)

Answer 33

1. Suspected pathogen must be consistent. 2. Must be isolated and noted. 3. Disease must be produced on a healthy plant with isolated oragnism. 4. The same pathogen must be isolated from the inoculated plant.

Question 34

hyphae

Answer 34

microscopic filaments which have defined cell walls.

Question 35

mycelium

Answer 35

alot of hyphae.

Question 36

septate

Answer 36

hyphae that are divided by crosswalls or sepa

Question 37

nonseptate

Answer 37

hyphae without septa

Question 38

haustorium

Answer 38

special absorbing organs; may be simple knob, long tube, or variously branched.

Question 39

sclerotium

Answer 39

dense compacted aggregate of mycelium

Question 40

appresium

Answer 40

swollen tip of hypa or germ tube that facilitates attachment and penetration of host.

Question 41

infection peg

Answer 41

arises from appresium and goes into the cell wall and cuticle.

Question 42

spores

Answer 42

sepcialized propagated units produced by fungi.

Question 43

intracellular

Answer 43

penetrates into host cells, absorbs food directly from host protoplasm

Question 44

intercellular

Answer 44

penetrate between cells, absorb food as it diffuses out of cells.

Question 45

external mycelia

Answer 45

live on plant surface.

Question 46

correct term for food source

Answer 46

food substrate

Question 47

asexual spores

Answer 47

one or more types per species

Question 48

sexual spores

Answer 48

one type per species

Question 49

the normal chromosome content of most fungi is?

Answer 49

haploid

Question 50

Plasmogamy

Answer 50

fusion of cells bringing two sexually compatible haploid nuclei into one cell.

Question 51

Karyogamy

Answer 51

nuclear fusion, forming a diploid nucleus.

Question 52

dikaryotic

Answer 52

having 2 haploid nuclei per cell.

Question 53

teleomorph

Answer 53

perfect stage, sexual spores only.

Question 54

anamorph

Answer 54

asexual spores only, imperfect stage.

Question 55

holomorph

Answer 55

spores in all stages, sexual and asexual