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Plant Pathology > Exam 3 > Flashcards

Exam 3 Flashcards

1
Q

What is an abnormal physical state, physiological malfunctioning, disordered or incorrectly functioning, or a deviation from the normal functioning?

A

Disease

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2
Q

What physiological function’s purpose is sugar production?

A

Photosynthesis

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3
Q

What physiological function’s purposes are movement, storage, etc?

A

Sugar allocation

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4
Q

What physiological function’s purposes are uptake, movement, allocation, and retention?

A

Water balance

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5
Q

What physiological function’s purposes are respiration, transcription/translation, membrane integrity?

A

Cell functions

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6
Q

What physiological function’s purposes are cells, tissues, fertilization, etc?

A

Growth and reproduction

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7
Q

How does TMV affect photosynthesis?

A

Attacks chloroplasts

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8
Q

How does HLB affect photosynthesis?

A

Blocks phloem, no energy for photosynthesis

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9
Q

How do foliar nematodes affect photosynthesis?

A

Destruction of leaf cells

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10
Q

How is sugar allocation affected by rust, root rots, or nematodes?

A

Nutrient deficiency

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11
Q

What pathogens affect water balance?

A

Pythium, wilts, fire blight, nematodes

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12
Q

What pathogens affect cell functions?

A

Rots, crown gall, nematodes, rhizoctonia, viruses

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13
Q

What pathogens affect growth and reproduction?

A

Crown gall, HLB

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14
Q

Fire blight: Necrotroph or Biotroph?

A

Necrotroph

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15
Q

Which polysacharide factors are affected by fire blight? How?

A

Amylovoran, levan: clog xylem

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16
Q

Which protein factor is affected by fire blight? How?

A

DspA/E: disrupts photosynthesis

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17
Q

Amylovoran requisite for…

A

biofilm formation

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18
Q

Levan contributes to…

A

biofilm

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19
Q

What is the 3-step process of DspE/A?

A
  1. Interacts with/binds to a precursor-ferredoxin.
  2. Pre-Fd imported into chloroplasts, converted to Fd (Fd serves as an electron carrier in PS1)
  3. Bound Pre-Fd unavailable for use (ETC impaired due to lack of Fd)
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20
Q

Which plant disease is a soilborne fungus (ascomycete), infects through roots, produces macro- and microconidia, and moves upwards in xylem?

A

Fusarium Wilt

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21
Q

Which plant disease has symptoms of older leaves first, “yellow flag” and red-brown vascular discoloration?

A

Fusarium Wilt

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22
Q

Which host compound impairs water movement using the protoplast of the adjacent cell?

A

Tyloses

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23
Q

Which host compound uses plant polysaccharide to impair water movement?

A

Callose

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24
Q

Which host compound uses plant protein and binds to carbohydrates to impair water movement?

A

Lectin

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25
Q

Which plant disease affects water movement because there is no increased transpiration, no reduced root uptake and the xylem is blocked?

A

Fusarium wilt

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26
Q

Nutrients are reliant upon…

A

water movement

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27
Q

Which plant disease is fastidious, phloem-limited and vectored by psyllids? It is also called “yellow dragon” and its yellowing starts on one limb.

A

HLB (Citrus Greening)

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28
Q

HLB affects callose and lectin (HR response), disrupts carbohydrate transfer, and causes sugar to back up. What does these three things cause?

A

Phloem plugging and necrosis

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29
Q

HLB causes accumulation of starch in chloroplasts and disrupts the plasma membrane causing ____ ____.

A

Starch packing.

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30
Q

What effects on reproduction does HLB have? (4)

A

Reduced flower set, reduced fruit number and size, malformed and bitter fruit, aborted seeds

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31
Q

TMV translation can reach ___% of total protein production in infected cells.

A

50

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32
Q

The viral proteins and genomes of TMV are ~__% of the leaf’s fresh weight.

A

1

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33
Q

The virus RNA of TMV contains _____ ______.

A

Enhancer structures

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34
Q

How does TMV affect photosynthesis? (3)

A

Reduction in chlorophyll and carotenoid, reduced ETC activity in isolated chloroplasts, reduced activity of PS II

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35
Q

What are the 3 steps of the central dogma of genetics?

A
  1. DNA carries code (genes)
  2. Code is transcribed into mRNA
  3. mRNA is translated into protein
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36
Q

What is the term for when genes are turned on or off?

A

Gene expression

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37
Q

2 types of gene expression

A

constitutive and induced

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38
Q

What are the 4 regulatory regions of DNA?

A

Promoters, enhancers, terminators, silencers

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39
Q

What is the ultimate source of variability in DNA?

A

Mutation

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40
Q

What are 4 possibilities of mutation that causes changes in DNA?

A

Base addition, base deletion, base substitution, transposable elements

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41
Q

What occurs when mutations are passed around?

A

Recombination

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42
Q

What are 4 ways recombination can occur?

A

Sex, Heterokaryosis, Parasexualism, Horizontal Gene Transfer, Co-infection by multiple viruses

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43
Q

Which 3 organisms participate in sex for means of recombination?

A

Fungi, Oomycetes, Nematodes

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44
Q

Which 2 organisms are heterokaryotes (recombination)?

A

Fungi, Oomycetes

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45
Q

Which 2 organisms are parasexual?

A

Fungi, Oomycetes

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46
Q

Which organism is capable of Horizontal Gene Transfer?

A

Bacteria

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47
Q

How does parasexualism contribute to recombination?

A

The nuclei are fused in a heterokaryon and reverts to 1N by discarding chromosomes in mitosis.

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48
Q

Which type of reproduction increases diversity?

A

Sexual

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49
Q

In the gene flow of ____ _____, the next generation has SOME new genes, new combinations may be advantageous, and a new feature may be diluted or lost.

A

Sexual

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50
Q

In the genotype flow of ____ ____, the entire genotype moves in a boom or bust fashion.

A

Asexual

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51
Q

A large population indicates which two things regarding mutations?

A

Larger number of mutants, larger likelihood of mutants reproducing

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52
Q

What is the changes in allele frequency due to random events?

A

Genetic drift

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53
Q

What is the capability of a pathogen to cause disease?

A

Pathogenicity

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54
Q

What are factors essential to disease development?

A

Pathogenicity factors

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55
Q

Pathogenicity factors are encoded by one or more ____ _____.

A

Pathogenicity genes

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56
Q

What is the degree of pathogenicity?

A

Virulence

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57
Q

What factors are not essential to disease development and are encoded by virulence genes?

A

Virulence factors

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58
Q

What is the ability of a pathogen to survive and reproduce?

A

Pathogen fitness

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59
Q

4 factors affecting pathogen fitness:

A
  1. Growth/multiplication rate
  2. Reproductive rate
  3. Infection efficiency
  4. Aggressiveness (amount of disease caused)
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60
Q

What are 4 ways a pathogen can be defined beyond species?

A
  1. Variation by host species
  2. Variation by host cultivar/variety
  3. Localized population (by field)
  4. Clonal population (by individual)
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61
Q

What 3 ways can host species variation be broken down for fungi, bacteria, and viruses?

A

Variety or forma specialis (Fungi), variety of pathovar (Bacteria), Type (virus)

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62
Q

When pathogen variation defined by host cultivar/variety, Fungi/Bacteria are defined by ____ and Viruses by _____.

A

Race, Strain

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63
Q

In the localized population, which are defined as “isolate?”

A

Fungi, bacteria

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64
Q

In the clonal population, Fungi are classified as ____, Bacteria by _____, and Viruses by ____ ____ ____ _____.

A

Biotype, strain, single local lesion isolate

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65
Q

Pathogen or host?

Has pathogenicity genes, infects at least one host, maybe hundreds

A

Pathogen

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66
Q

Pathogen or host?

Combination of genes makes it susceptible to some pathogens, non-host to most pathogens

A

Host

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67
Q

Which type of resistance is outside the host range of the pathogen?

A

Non-host

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68
Q

Which type of resistance has genes specific to recognizing and defeating the pathogen?

A

Resistance genes

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69
Q

Which type of resistance has two subsets: escape and tolerance?

A

Apparent resistance

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70
Q

Which subset of apparent resistance is when the host is not infected due to avoidance of disease interaction (disease triangle)?

A

Escape

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71
Q

Which subset of apparent resistance is when the host is infected, but not highly damaged?

A

Tolerance

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72
Q

How is horizontal “true” resistance defined? (4)

A
  1. Not specific to one pathogen
  2. Controlled by multiple genes (usually)
  3. Genes control various steps/aspects of plant defense systems
  4. Doesn’t prevent infection, but slows subsequent steps of disease cycle
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73
Q

How is vertical true resistance defined? (3)

A

Clear difference in resistance to certain pathogen races (race-specific), resistance conferred by ONE or a few gene(s), R genes control pathogen recognition

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74
Q

What are the 3 reactions of vertical true resistance?

A

Apparent immunity, hypersensitive response, inhibition of pathogen reproduction

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75
Q

Which type of vertical true resistance reaction shows no infection?

A

Apparent immunity

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76
Q

Which type of vertical true resistance reaction shows no colonization?

A

Hypersensitive response

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77
Q

Which type of resistance stability has complete resistance under most conditions and is defeated by one or a few pathogen mutations?

A

Race specific (R gene)

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78
Q

Which type of resistance stability has variable resistance, affected by conditions, and is more difficult to defeat because it requires many mutations?

A

Partial (Quantitative)

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79
Q

What resistance stability combination is when multiple R genes are stacked?

A

Pyramid

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80
Q

Each ____ ____ in a plant (R) has a corresponding ____ ____ (A) in the pathogen.

A

Resistance gene; virulence gene

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81
Q

Host resistance gene can only be identified by its _____ in the pathogen.

A

Counterpart

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82
Q

Which gene set (pathogen or host plant) has virulence usually recessive, gene codes for a pathogenicity or virulence factor, and the factor is termed the “elicitor” in the interaction?

A

Pathogen

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83
Q

Which gene set (pathogen or host plant) is the resistance usually dominant, the gene codes for a receptor which recognizes the elicitor, and if the elicitor is recognized - defenses are triggered?

A

Host plant

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84
Q

Gene for gene interactions:
a r
No elicitor molecules
No receptor on host

Will host recognize pathogen?
Will interaction result in disease?

A

No

Yes

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85
Q

Gene for gene interactions:
a R
No elicitor molecules
Receptor on host

A

No

Yes

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86
Q

Gene for gene interactions:
A r
Elicitor molecules
No receptor on host

A

No

Yes

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87
Q

Gene for gene interactions:
A R
Elicitor molecules
Receptor on host

A

Yes

No

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88
Q

AR

Resistant or susceptible?

A

Resistant (-)

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89
Q

Ar

Resistant or susceptible?

A

Susceptible (+)

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90
Q

aR

Resistant or susceptible?

A

Susceptible (+)

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91
Q

ar

Resistant or susceptible?

A

Susceptible (+)

92
Q

One pathogen can produce many elicitors and a host can have many resistance genes. In this case, will disease occur?

A

No, it only needs to recognize one elicitor to intiate defenses.

93
Q

An ___ combination for ANY gene will result in recognition and resistance.

A

AR

94
Q

A plant variety with no ____ ____ is susceptible to all pathogen races.

A

resistance genes

95
Q

A pathogen that produces no _____ _____ can cause disease on host varieites.

A

recognizable elicitors

96
Q

What are two reasons pathogens produce elicitors?

A

Pathogenicity factors: vital to critical steps in the disease cycle
Virulence factors: advantageous in causing disease , enabling disease on particular host varieties

97
Q

What component is required for appressorium wall reinforcement?

A

Melanin

98
Q

What is the required step for pathogenicity (quorum sensing to swarm)?

A

Type IV Pili for aggregation

99
Q

Bacterial Secretion System #

Most plant pathogenic bacteria, toxin secretion

A

Type I

100
Q

Bacterial Secretion System #

Gram (-), export of proteins, toxins, virulence factors

A

Type II

101
Q

Bacterial Secretion System #

Gram (-), Transport of effector proteins into plant cell

A

Type III

102
Q

Bacterial Secretion System #

Transport of macromolecules to host cell

A

Type IV

103
Q

Bacterial Secretion System #

Surface-associated adhesins

A

Type V

104
Q

Which type of bacterial secretion system is a gram (-) bacteria that can interact with a host, uses an injectisome as a delivery apparatus, and has a Hrp system?

A

Type III SS

105
Q

What is a cluster of pathogenicity related genes regulated together and sometimes found on plasmids?

A

Pathogenicity island

106
Q

What are proteins required for the production of T3SS?

A

hrp

107
Q

What are proteins required to assemble the injectisome?

A

hrc

108
Q

What are virulence genes that determine the host range?

A

avr

109
Q

What are hrp-dependent outer proteins (effector proteins)?

A

hop

110
Q

R Genes have which 3 things?

A

Receptors, signal transduction, 6 structural classes

111
Q

Which common, but not ubiquitous mechanism causes localized cell death?

A

HR response

112
Q

Which induced defense mechanism of the entire plant has a signal generated 4-6 hours after inoculation?

A

Systemic acquired resistance

113
Q

3 Steps of Staging an Invasion

A
  1. Enter Plant
  2. Avert Defenses
  3. Reap the Rewards
114
Q

What is produced via pathogenicity genes and essential for one or more steps in the disease progress on a host?

A

Pathogenicity factor

115
Q

3 types of mechanical entry

A

Fungi, Nematodes, Parasitic plants

116
Q

4 types of chemical entry

A

enzymes, toxins, growth regulators, polysaccharides

117
Q

What mechanical apparatus of fungi adheres, builds pressure, and concentrates pressure to penetrate?

A

Appressorium

118
Q

What are proteins that catalyze chemical reactions?

A

Enzymes

119
Q

What is an enzyme that is always produced?

A

Constitutive

120
Q

What is an enzyme whose production is turned on as needed?

A

Induced

121
Q

4 examples of cell wall degrading enzymes

A

Cutinases (and esterases)
Pectinases
Cellulases
Ligninases

122
Q

4 examples of cell content degrading enzymes

A

Proteases
Amylases
Lipases
Phospholipases

123
Q

What causes direct injury to host cells by permeability of membranes and inhibition/inactivation of enzymes?

A

Toxins

124
Q

What type of toxin affects only the host plant?

A

Host-specific

125
Q

What type of toxin affects a wide range of plants?

A

Nonhost-specific

126
Q

Tabtoxin (Pseudomonas syringae) is a host-specific/nonhost-specific toxin.

A

Nonhost-specific

127
Q

Which nonhost-specific toxin inactivates glutamine synthetase?

A

Tabtoxin (Pseudomonas syringae)

128
Q

Cercosporin is a host-specific/nonhost-specific toxin.

A

Nonhost-specific

129
Q

Which nonhost-specific toxin generates active oxygen and is light-activated?

A

Cercosporin

130
Q

T Toxin (Cochliobolus heterostrophus) is a host-specific/nonhost-specific toxin.

A

Host-specific

131
Q

What disease does T Toxin cause?

A

Southern Corn Leaf Blight

132
Q

What years had isolated incidences of Southern Corn Leaf Blight?

A

1968-1969

133
Q

In 1970, ___% of corn was TMS.

A

85

134
Q

Alternaria alternata toxin is a host-specific/nonhost-specific toxin.

A

Host-specific

135
Q

Which host-specific toxin has multiple pathotypes where each produces a different form of toxin?

A

Alternaria alternata

136
Q

Which toxin causes black spot on Japanese pear?

A

AK toxin

137
Q

Which toxin causes stem canker on tomato?

A

AAL toxin

138
Q

Which toxin causes issues on strawberries?

A

AF toxin

139
Q

Which toxin causes issues on apples?

A

AM toxin

140
Q

Which 3 alternaria toxins disrupt the plasma membrane?

A

ACT, AF, AK

141
Q

Which alternaria toxin disrupts the plasma membrane and chloroplast?

A

AM

142
Q

Which alternaria toxin causes the mitochondria to malfunction?

A

ACR

143
Q

What are 4 plant growth hormones?

A

Auxins (IAA)
Gibberelins
Cytokinins
Ethylene

144
Q

What other compounds function as growth regulators?

A

Growth inhibitors

145
Q

What are the pathogenic effects of growth regulators?

A

Induce plant production and pathogen production

146
Q

What polysaccharide functions in lubrication, protection, and disguise?

A

Mucilage, “slime”

147
Q

What is pathogens are associated with mucilage?

A

Bacteria, fungi, nematodes

148
Q

What are the major effects of mucilage?

A

Wilts

149
Q

What are the 4 types of plant defenses?

A

Physical, Chemical, Induced, Preexisting

150
Q

Which preexisting defense mechanism has structural components that physically block adhesion, entry, and movement of pathogens?

A

Physical

151
Q

Which preexisting defense mechanism has inhibitors that prevent germination, growth, enzyme production/function of pathogens, and the absence of toxin molecules prevents pathogen recognition of the host, rendering pathogen toxins ineffective/

A

Chemical

152
Q

Which induced plant defense is when structural components are altered or reinforced?

A

Physical

153
Q

which induced plant defense is when the inhibitor production is initiated/increased and HR response prevents pathogen colonzation?

A

Chemical

154
Q

Which plant surfaces are hydrophobic and reduces formation of water films?

A

Waxes and trichomes

155
Q

Which plant surfaces provide a barrier to direct penetration?

A

Cuticle and epidermal cell walls

156
Q

Which plant surface defenses cause reduced opportunity for entry?

A

Stomatal structure and timing

157
Q

What are the 3 reinforced cells of plant interiors?

A

Xylem, bundle sheath, sclerenchyma

158
Q

What is the primary function of reinforced cells?

A

Limit movement of pathogens within the plant

159
Q

Chitinases and B-1,3,-glucanases break down ___ cell walls.

A

Fungal

160
Q

Chemical defenses in plant interiors (4)

A

Phenolic compounds, tannins, saponins, enzyme inhibitors

161
Q

All induced defenses require _____.

A

Recognition

162
Q

What are 4 examples of nonspecific elicitors?

A

Toxins, carbohydrates, fatty acids, enzymes

163
Q

What are 2 examples of specific elicitors?

A

avr gene products, hrp products

164
Q

Success of defenses depends on which two things?

A

Speed of recognition and speed of reaction

165
Q

What are 4 types of induced physical defenses?

A

Cell wall structures
Histological strucutres
Cytoplasmic reaction
Necrotic/hypersensitive reaction

166
Q

Considering cell wall defense structures, what 3 changes occur in the cell wall?

A

Thickening, reinforcement, deposition of phenols

167
Q

What 4 histological defense structures form ahead of the pathogen?

A

Cork layers, abscission layers, tyloses, gum deposition

168
Q

HR reactoin is a common reaction to which 4 things?

A

Obligate fungal pathogens, viruses, bacteria, nematodes

169
Q

Which effect of induced chemicals inhibits germination and lyses cell wall components? This directly inhibits the pathogen.

A

Direct effects

170
Q

Which effect of induced chemicals affects host cell wall structures and is induced in the host or environment?

A

Indirect effects

171
Q

What induced chemical causes a direct inhibition of the pathogen and its enzymes?

A

Phenolics

172
Q

Which induced chemical is toxic to fungi and is induced by invasion or injury?

A

Phytoalexins

173
Q

What are the 7 environmental factors?

A

Temperature, moisture, wind, light, soil characteristics, nutrient availability, human-made herbicides and pollutants

174
Q

What is the optimum temperature range for the pathogen F. oxysporum?

A

22-28 C

175
Q

What is the optimum temperature range for the onion host of F. oxysporum?

A

28-32 C

176
Q

What is the optimum temperature for disease in onion for F. oxysporum?

A

17-23 C

177
Q

What is the optimum temperature for the pathogen Thielaviopsis basicola on tobacco?

A

22-28 C

178
Q

What is the optimum temperature for tobacco host in regards to T. basicola?

A

28-32 C

179
Q

What is the optimum temperature for disease in tobacco for T. Basicola?

A

17-23 C

180
Q

In _____, the higher the soil temperature, the higher prevalence of disease.

A

Pansy

181
Q

In ____, the lower the soil temperature, the higher prevalence of disease.

A

Cotton

182
Q

What are the 7 roles of moisture?

A

Dispersal, pathogen germination/growth, signal movement, penetration, host defenses, secondary dispersal, survival

183
Q

Apple scab optimal growth is at what temperature?

A

16-24 C

184
Q

How does wind increase disease?

A

Pathogen dispersal and leaf injury

185
Q

How does wind decrease disease?

A

Leaf drying

186
Q

Shading (etiolation in high-light plants) causes what 4 things?

A

Increased opportunistic pathogens, decreased obligate pathogens, increased susceptibility to viruses, decreased severity of viral disease

187
Q

Excessive light in shade-adapted plants can cause___ ____ in which plants for example?

A

More disease; coffee berry

188
Q

Pathogen effects of light (3)

A

Light cues in pathogen physiology, light and pathogenicity factors, light damage

189
Q

Apple scab ascospore release (3) things

A

Requires wetness, triggered by light, increases with temperature

190
Q

2 host effects of soil texture and structure

A

Drainage, waterlogging

191
Q

3 pathogen effects of soil texture and structure

A

reproduction, movement, survival

192
Q

2 host effects of soil pH

A

host pH range, nutrient availability

193
Q

2 pathogen effects of soil pH

A

pathogen pH range, enyzme activity

194
Q

2 host effects of nutrients

A

growth rates, plant health and resistance

195
Q

Nitrate increases which 3 pathogens

A

P. omnivora, G. graminis, S. scabies

196
Q

Ammonium increases which 3 pathogens

A

Fusarium spp, P. brassicae, S. rolfsii

197
Q

4 issues with herbicides or air pollution

A

damage to plants, pathogen effects, soil microbe effects, surrounding plant effects

198
Q

Change in disease intensity within a host population over time and/or in space

A

epidemiology

199
Q

Who created the first epidemiological forecasting system by creating tables showing duration of rain required at different temperatures for V. inaequalis infection (apple scab)?

A

Mills, 1944

200
Q

Who published Plant Disease: Epidemics and Control, which showed mathematical models in epidemiology and monocyclic vs. polycyclic pathogens?

A

Van Der Plank, 1963

201
Q

In the disease triangle, what do epidemiologists include as the 4th factor?

A

Time

202
Q

What do epidemiologists include under environmental conditions?

A

Vectors

203
Q

The disease progress curve shows the change in ______ variable over _____

A

Disease; time

204
Q

On the disease progress curve, the percent of plants infected is called _____.

A

Incidence

205
Q

On the disease progress curve, the disease rating is also called _____.

A

Severity

206
Q

When measuring disease, which term is a binary measure (yes/no) and expressed as a percentage?

A

Incidence

207
Q

When measuring disease, which term is a quantitative or semi-quantitative measure that has a variety of metrics?

A

Severity

208
Q

When measuring severity, what are 3 variety of metrics used?

A

Percent leaf area, lesion size, symptom progression

209
Q

How do you compare multiple disease progress curves?

A

Calculating the area under the disease progress curve

210
Q

What is a unitless, quantitative summary that allows for comparison of disease progress curves?

A

AUDPC

211
Q

In reference to quantity of inoculum, what is the number of propagules per unit weight or volume?

A

Inoculum density

212
Q

What two factors indicate quality of inoculum?

A

Infectivity, inoculum potential

213
Q

What is a measure of inoculum quantity and quality that shows the energy available for colonization of a host at the surface to be colonized?

A

Inoculum potential

214
Q

What two components are required to measure and interpret inoculum potential?

A

Inoculum density, proportion of inoculum that can infect

215
Q

What is required to measure and interpret inoculum potential?

A

Bioassay

216
Q

What 3 things do modeling epidemics allow us to do?

A

Describe disease progress, compare progress under different conditions, and predict progress under different conditions

217
Q

3 characteristics of monocyclic diseases

A

One infection cycle per growing season
No secondary inoculum within season
Typical of most soilborne pathogens

218
Q

3 characteristics of polycyclic diseases

A

Multiple cycles per growing season
Secondary inoculum produced
Typical of most airborne pathogens

219
Q

Monocyclic or Polycyclic?

Disease progress curve is typically a saturation curve.

A

Monocyclic

220
Q

Monocyclic or Polycyclic?

Disease progress curve is typically a sigmoid curve.

A

Polycyclic

221
Q

Spatial spread from an inoculum source

A

Pathogen dissemination

222
Q

Disease forecasting is useful when: (1)

A

The disease is sporadic or occurs repeatedly at certain locations and control strategies are available.

223
Q

Disease forecasting is NOT useful when: (2)

A

The disease is always severe

There is no control measure available

224
Q

How is the disease triangle used in disease forecasting? (3)

A

Pathogen biology, environmental parameters, pattern of disease progress

225
Q

What are 2 things that are the basis of forecasting?

A

amount of inoculum (primary and/or secondary) and weather conditions that favor the disease

226
Q

What is the forecast system of BLITECAST? (4)

A

Assumes presence of inoculum.
Temperature and RH predict severity values
SV accumulate over time
First fungicide application when threshold is reached (18 SV)

227
Q

What is the forecast system of tobacco blue mold? (2)

A

Outbreaks (sources) reported to forecaster.

NOAA database used to create trajectory model.

Plant Pathology (5 decks)

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