Exam #1

Question 1

sustained physiological and structural issue that affects some or all plant processes

Answer 1

plant disease

Question 2

series of steps to isolate and determine what causes a disease; cannot be done with every disease

Answer 2

Koch’s Postulate

Question 3

fungi, bacteria, viruses, and nematodes

Answer 3

biotic agents

Question 4

non-bio factors (climate, mechanical)

Answer 4

abiotic agents

Question 5

obtain nutrients from dead organic matter

Answer 5

saprophytes

Question 5

organism that grows inside the plant to complete its lifecycle and therefore has a detrimental affect on the plant

Answer 5

plant pathogen

Question 5

obtain nutrients from another organism

Answer 5

parasites

Question 5

need a host to live; only gets nutrients from living material

Answer 5

biotroph/obligate parasite

Question 5

kill host and then take nutrients

Answer 5

necrotroph

Question 6

feed on living and/or dead tissue; usually asymptomatic at first, later turns to killing tissue

Answer 6

hemibiotrophs

Question 7

live on dead organic matter ONLY; decomposers

Answer 7

obligate saprophytes

Question 8

better adapted as parasites, but can live as a saprophyte; adopted the ability to feed on dead OM

Answer 8

facultative saprophyte

Question 9

better adapted as saprophyte, but can survive as a parasite when needed; adopted ability to be a parasite

Answer 9

facultative parasite

Question 10

external/internal reactions of a plant caused by the disease - galls, leaf spot

Answer 10

symptom

Question 11

pathogen itself shown on the plant - rust spores, powdery mildew

Answer 11

signs

Question 12

environment, pathogen, and host (also time)

Answer 12

disease triangle

Question 13

plant cannot be infected

Answer 13

immune

Question 14

plant can be infected

Answer 14

suceptible

Question 15

plant may be infected, but won’t allow pathogen to proliferate

Answer 15

resistance

Question 16

plant can be infected and disease can spread, but the plant will survive

Answer 16

tolerant

Question 17

order of disease development

Answer 17

1. dispersal of pathogen to host
2. penetration and infection of host
3. invasion and colonization of host
4. reproduction of pathogen
5. dispersal of new host
6. pathogen survival over winter

Question 18

steps in life cycle that lead to disease

Answer 18

disease cycle

Question 19

structure/part of pathogen that starts the infection

Answer 19

primary inoculum

Question 20

method through which a pathogen gains access to a host - spores, insect transport

Answer 20

dispersal of inoculum

Question 21

location where the infection starts

Answer 21

infection court

Question 22

process of successfully infecting a host

Answer 22

colonization

Question 23

produced on an infected plant that can lead to new infections during the same growing season

Answer 23

secondary inoculum

Question 24

complete only 1 cycle of development (only primary inoculum) - reduce the amount/efficiency of primary inoculum to manage

Answer 24

monocyclic

Question 25

complete more than 1 cycle of development (primary and secondary inoculum) - reduce primary inoculum and reduce the rate of secondary infections; only controlling primary doesn't do much - **sigmoid curve

Answer 25

polycyclic

Question 26

don't bring pathogen to the host - time when inoculum isn't present - take out 1 of the categories in the disease triangle

Answer 26

avoidance

Question 27

prevent the introduction of the pathogen; quarantine; plant seed is free of pathogen before planting (seed indexing)

Answer 27

exclusion

Question 28

destroying disease by removing infected material; solarization to kill pathogen

Answer 28

eradication

Question 29

chemical, biological, and cultural practices to prevent infection and disease

Answer 29

protection

Question 30

closer relatives to animals (glycogen, chitin in cell walls), eukaryotic, haploids

Answer 30

fungi

Question 31

sexual spores produced in asci (sacs); septate hyphae generally with two haploid nuclei in each cell; 8 ascospores

Answer 31

ascomycetes

Question 32

sexual spores produced in basidia (club-shaped); 4-spore cells; hyphae with 2 haploid nuclei in each cell; clamp connection

Answer 32

basidiomycetes

Question 33

fungus-LIKE organisms; water molds; absorb nutrients thru cell walls with cellulose; have hyphae; feed on decaying matter

Answer 33

oomycetes

Question 34

motile spores that swim thru water to sear for food; 2 flagella with different structures and functions

Answer 34

zoospores

Question 35

filamentous vegetative bodies branching out in all directions (hyphae = individual branches)

Answer 35

mycelium

Question 36

roles of hyphae

Answer 36

nutrient acquisition, penetration, networking, survival structures, proliferation, mating, fusion, and fruiting body production

Question 37

nutrient acquisition and growth are related (hyphae must move towards food)

Answer 37

trophic growth

Question 38

reproduce by budding; no hyphae; single cells

Answer 38

yeast

Question 39

bulb outside the infection zone of hyphae

Answer 39

appresorium

Question 40

specialized fungal hyphae that penetrates cell walls and expands inside the cells; nutrient acquisition and interaction between fungi and the host; surrounded by the host cell membrane; only penetrates thru the cell wall

Answer 40

haustoria

Question 41

neighboring hyphae fuse together for circulation and important for mating

Answer 41

hyphal fusion

Question 42

self fertilization (uniform)

Answer 42

homothallic

Question 43

out-crossing fungi (diversity)

Answer 43

heterothallic

Question 44

specialized hyphae; holds spores and produces and releases them; sexual or asexual

Answer 44

fruiting bodies

Question 45

classic mushrooms - few are pathogens

Answer 45

basidiocarps

Question 46

morels and small fruiting bodies

Answer 46

ascocarps

Question 47

formed under adverse conditions (host, climate, pH); perennial fruiting bodies can last for several years

Answer 47

survival structures

Question 48

hardened masses of hyphae that contain fruiting bodies

Answer 48

stroma

Question 49

masses/balls of hyphae that can stay for several years; dark in color because it has melanin to protect it from the sun

Answer 49

sclerotia

Question 50

melanized hyphal ropes

Answer 50

rhizomorphs

Question 51

hyphae that fully encases the host tissue

Answer 51

mummies

Question 52

wind, water, and vectored dispersal

Answer 52

passive dispersal

Question 53

motile spores, forceable ejection

Answer 53

active dispersal

Question 54

hyphae that produces spores without the genetic variation

Answer 54

conidiophores

Question 55

fungal disease cycle

Answer 55

1. dissemination/ transmission 2. arrival and attachment 3. infection 4. colonization 5. survival

Question 56

from one unrelated host to another

Answer 56

horizontal transmission

Question 57

from parent to progeny

Answer 57

vertical transmission

Question 58

infect directly thru the cell walls of a host

Answer 58

direct penetration

Question 59

fungi can induce plant defense response that's harmful to itself - air bubbles (tyloses) to prevent fungus from spreading

Answer 59

autotoxicity

Question 60

stimulate host to produce growth hormones leading to deformities - more to feed on for parasite

Answer 60

growth deformity

Question 61

where exclusion, eradication, and avoidance is highly effective

Answer 61

facultative saprophytes and obligate parasites

Question 62

where exclusion, eradication, and avoidance isn't as effective - use protection!

Answer 62

facultative parasites

Question 63

microscopic non-segmented round worms

Answer 63

nematodes

Question 64

can determine whether it's parasitic or not (nematodes) - parasitic have these

Answer 64

stylets

Question 65

nematode life cycle

Answer 65

egg --> 4 juvenile stages --> adult infection occurs during juvenile 2 stage