Pathology L1

Question 1

Phytopathology

Answer 1

Study of plant disease caused by biotic and abiotic factors

Question 2

Disease

Answer 2

Any problem of plant cells and tissues that result from a pathogenic or environmental factor that leads to symptoms

Question 3

Symptom

Answer 3

Reaction of plant to disease

Question 4

Sign

Answer 4

Physical evidence of a pathogen

Question 5

Examples of a sign

Answer 5

Fungal pathogen - mycelium, fruiting bodies
Bacterial pathogen - exudates

Question 6

Pathogen

Answer 6

Disease causing organism that negatively affects the host

Question 7

Host

Answer 7

Living organism that is attacked by the parasite or pathogen

Question 8

What does disease do?

Answer 8

Interrupts function and damages cells and tissues

Question 9

Results of disease on roots/crown

Answer 9

Gall and root rot result in wilting in later stages

Question 10

Results of disease on stems

Answer 10

Results in lodging of plants

Question 11

Results of disease on leaves

Answer 11

Reduces photosynthetic area of the plant

Question 12

Results of disease on flower/fruit

Answer 12

Reduces yield, quality of fruit/grain

Question 13

Chlorosis

Answer 13

Yellowing of leaves due to reduced chlorophyll

Question 14

Necrosis

Answer 14

Death of tissue

Question 15

Symptoms of disease

Answer 15

Chlorosis, necrosis, galls/tumors, wilts, scabs, cankers/lesions/pustules

Question 16

Healthy plant

Answer 16

Carries out physiological functions and grows to bet of its genetic potential

Question 17

Diseased plant

Answer 17

Malfunctioning of host cells and tissues duets pathogenic agent or environmental factor
Abnormal changes in form or integrity of plant
May cause partial impairment or death of host

Question 18

Examples of abiotic stresses

Answer 18

Cold, heat, flooding, drought, salinity, heavy metal

Question 19

Water stress

Answer 19

To much (waterlogged) or too little (drought)

Question 20

Temperature stress

Answer 20

Freezing
too hot causing desication, wilting, abortion, etc

Question 21

Phytotoxicity

Answer 21

Harm or adverse effects to a plant caused by specific substances or growing conditions (chemicals)

Question 22

What info is required to diagnose symptoms

Answer 22

Crop rotation history
Herbicide history
Fertilizer history
Crop seeding date
Weather conditions
Pesticide application info

Question 23

Parasite

Answer 23

Organisms that lives on or in another organism and obtains food from it

Question 24

Parasitism

Answer 24

Removal of food by a parasite from its host

Question 25

Symbiosis

Answer 25

Benefits host and parasite

Question 26

Example of symbiosis

Answer 26

Mycorrhiza

Question 27

Example of parasitism

Answer 27

Sclerotinia

Question 28

Pathogen

Answer 28

Organism that induces disease

Question 29

Pathogenicity

Answer 29

The ability of a parasite to interfere with 1 or more of a plants essential functions

Question 30

Host range

Answer 30

Number of hosts a pathogen can use

Question 31

Covered south infects plants from a ________ family. What family?

Answer 31

Single. Grass family

Question 32

Sclerotinia sclerotiorum infects plants from a __________ family

Answer 32

Diverse

Question 33

When and what does covered smut infect

Answer 33

Early stage at seed germination, leaf and inflorescence

Question 34

When and what does sclerotinia sclerotiorum infect

Answer 34

Various stages, any part of the plant

Question 35

5 main strategies of the lifestyle of plant microbes

Answer 35

Biotrophic parasitism Necrotrophic parasitism Hemi-biotrophic parasitism Saprophytic Symbiotic

Question 36

Biotrophic parasitism

Answer 36

Pathogens that depend on host as a source of nutrients and don't kill the host

Question 37

2 types of biotrophic parasitism

Answer 37

Obligate and non-obligate parasites

Question 38

Obligate parasites

Answer 38

Complete life cycle occurs in living host cell

Question 39

Non-obligate (facultative) parasites

Answer 39

Live on host for part, but complete life cycle on dead organic matter

Question 40

Examples of biotrophic parasitism

Answer 40

Powdery mildew on barley General rust infections

Question 41

Necrotrophic parasitism

Answer 41

Lives in or on living plant but kills the tissues with enzymes that disintegrate cell components before consuming nutrients from them

Question 42

Hemi-biotrophic parasitism

Answer 42

Combination of bio and necrotrophic strategies that is initially biotrophic and then necrotrophic (steal than kill)

Question 43

Saprophytic

Answer 43

Lives on dead organic matter where host tissues are not killed by organism but used by them

Question 44

Example of saprophytic

Answer 44

Alternaria raphanin and gymnopilus junonius

Question 45

Symbiotic

Answer 45

The smaller organism in a symbiotic relationship which lives in or on the host

Question 46

For a plant to become diseased, there must be....

Answer 46

A host (susceptible plant) A pathogen Contact between the host and pathogen and conductive environmental conditions

Question 47

Factors of the disease triangle

Answer 47

Pathogen, host, environment

Question 48

Virulent

Answer 48

Ability of pathogen to cause disease on a host

Question 49

Avirulant

Answer 49

Inability of pathogen to cause disease on a host

Question 50

Innoculum

Answer 50

Form of a pathogen which can infect a host plant to cause disease

Question 51

Infection

Answer 51

Successful entry of pathogen followed by growth, multiplication of the pathogen in the host

Question 52

5 classes of biotic disease stressors

Answer 52

Fungi Bacteria Mollicutes Parasitic higher plants Viruses Nematodes