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Plant Pathology > Exam 2 > Flashcards

Exam 2 Flashcards

1
Q

About how many species of bacteria cause plant diseases?

A

~100

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2
Q 
Fungi or Bacteria?
Smaller order of magnitude
Structural features difficult to see
Metabolically complex
Much less terminology
A

Bacteria

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3
Q

Visible mass of single cells

A

Colony

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4
Q

3 shapes of bacteria

A

Coccus, rod, curved rod

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5
Q

Cocci can be found in which 5 morphological structures?

A

single, pairs (diplococci), chains, tetrads, clusters

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6
Q

Rods can be found in which 5 morphological structures?

A

Bacillus (single), flagellated bacilli, chains, palisades, filaments

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7
Q

Curved rods can be found in which 3 morphological structures?

A

Single curved rod, spirilla, spirochetes

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8
Q

Which morphological shape of bacteria has no cell wall and can have varying shapes?

A

Pleomorphic

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9
Q

Which type of bacteria has a cell wall with thin peptidoglycan layer between two membranes?

A

Gram negative

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10
Q

Which type of bacteria has a cell wall with a single membrane and a thick peptidoglycan layer?

A

Gram positive

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11
Q

Which class of bacteria has a cell membrane but no cell wall?

A

Mollicutes

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12
Q

What rigid framework is responsible for cell shape and protects the cell from environmental stress?

A

cell wall

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13
Q

What are the 4 steps of gram staining?

A
  1. Crystal violet
  2. Iodine
  3. Wash with alcohol/acetone
  4. Safranin counterstain
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14
Q

What are the 4 steps of the KOH test?

A
  1. KOH on slide
  2. Collect bacteria from 24-48 hr colony
  3. Stir in KOH 5-10 sec
  4. Lift loop
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15
Q

In the KOH test, which type of bacteria has viscous slime?

A

Gram negative

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16
Q

Which type of flagellated bacteria have a single tail?

A

Monotrichous

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17
Q

Which type of flagellated bacteria have a tail on each end?

A

Amphitrichous

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18
Q

Which type of flagellated bacteria have many tails?

A

Lophotrichous

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19
Q

Which type of flagellated bacteria have tails all around its perimeter?

A

Peritrichous

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20
Q

Which bacterial structure is short and its primary function is attachment?

A

Fimbria

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21
Q

Which bacterial structure is longer and has multiple types with varying functions?

A

Pilus

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22
Q

Which pilus functions in attachment to surfaces?

A

Type 1

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23
Q

Which pilus functions in movement on surfaces (without flagella)?

A

Type IV

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24
Q

Which pilus functions in attachment to other bacteria for gene transfer?

A

Conjugation (Sex)

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25
Q

Which pilus functions in interaction with the host?

A

HrP

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26
Q

Which type of bacteria requires oxygen?

A

Obligate anaerobe

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27
Q

Which type of bacteria grows with or without oxygen?

A

Facultative anaerobe

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28
Q

Which type of bacteria grows best in low-oxygen conditions?

A

Microaerophilic

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29
Q

Which type of bacteria cannot survive in the presence of oxygen because it is toxic to them?

A

Strict anaerobe

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30
Q

What method do bacteria use to reproduce?

A

Fission - NO SEXUAL REPRODUCTION

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31
Q

Where do bacteria keep “extra” DNA?

A

plasmids

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32
Q

How do bacteria communicate?

A

Cell signaling - they use receptors to identify what’s around them

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33
Q

When bacteria swarm/multiply to reach a critical concentration for survival, this is an example of

A

Density-dependent communication

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34
Q

What two things are required for a plant bacterial infection to occur?

A

Critical mass (quorum) and an opening

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35
Q

Bacteria do not have spores like fungi, so their ______ is disseminated.

A

Entire body

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36
Q

A specialized survival structure in bacteria

A

Endospores

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37
Q

Do plant pathogenic bacteria produce endospores?

A

NO

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38
Q

Which 5 places do bacterial plant pathogens survive?

A 
In/on host tissues
In/on alternate hosts
In soil
On surfaces
In vector
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39
Q

What are 5 common disease symptoms of bacteria in plants?

A

Leaf spots & blights
Wilts
Rots
Galls, phyllody

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40
Q

What are 2 examples of bacterial signs?

A

Slime and ooze

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41
Q

Which bacterial plant disease is primarily found in rosaecous hosts, its main symptoms include flagging, shepherd’s crook, leaf & twig blight, and cankers on the main stem? Its signs include bacterial ooze from fruit, leaves, and stem cankers and it is one of the oldest known bacterial plant diseases?

A

Fire Blight - Erwinia amylovora

Gram Negative

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42
Q

What is the primary vector of fire blight?

A

Insects (bees)

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43
Q

Which bacterial plant disease is seedborne with symptoms including angular spots on leaves (initially water-soaked), deformation, necrotic margins, leaf drop, and small blister-like brown warty fruit spots?

A

Bacterial spot of pepper and tomato - Xanthomonas

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44
Q

Which bacterial plant disease has a wide host range and is pectolytic? It rots almost anything except the epidermis and its secondary bacterial colonization leads to a foul odor?

A

Soft Rots - Pectobacterium, Dickeya

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45
Q

Which bacterial plant disease is not harmful to humans, but causes fruit blotches on watermelon?

A

Watermelon fruit blotch - Acidovorax avenae citrulli

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46
Q

Which bacterial plant disease has a wide host range in dicots, is a soil inhabitant and its symptoms include gall formation near the soil line and girdling and plant death?

A

Crown gall - Agrobacterium tumefaciens

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47
Q

Which disease is a pathogen only because of the genes on its plasmid - it is not pathogenic on its own? What is the name of the plasmid?

A

Agrobacterium tumefaciens; Ti Plasmid

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48
Q

Which two plant genes are growth hormones whose overproduction causes galls in Agrobacterium tumefaciens?

A

Auxin, Cytokinin

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49
Q

Which bacterial plant disease is found in citrus plants and its symptoms include raised spots with oily, watersoaked margins and a yellow halo, defoliation, and early fruit drop?

A

Citrus canker - Xanthomonas citri

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50
Q

Citrus canker was introduced the first time in what year? The second time?

A

1910; 1986

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51
Q

The first time citrus canker was introduced, how long did it take to eradicate?

A

20 years

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52
Q

Which bacterial plant disease has a wide host range (solanaceae, banana, geranium, pothos), is a soil inhabitant infecting through the roots and moving upward through the xylem? Its symptoms include wilt and vascular discoloration.

A

Bacterial wilt - Ralstonia solanacearum

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53
Q

Which bacterial plant disease is a fastidious bacteria (picky eater), vector borne, and xylem-limited? Its symptoms include interveinal chlorosis, marginal necrosis, leaf drop, fruit shrivels, and plant death?

A

Pierce’s disease - Xylella fastidiosa

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54
Q

Which vector transmits X. fastidiosa?

A

Sharpshooters

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55
Q

Which bacterial plant disease is phloem-limited, vectored by psyllids and symptoms include chlorotic shoots, leaf mottling, small lopsided fruit, and dieback/tree death?

A

Huanglongbing - Candidatus Liberibacter (HLB, yellow dragon, citrus greening)

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56
Q

Disease cycle of HLB

A 
Psyllid feeds on infected tissue
Bacteria multiply in psyllid
Psyllid feeds on healthy tissue
Systemic spread in plant
Symptom development
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57
Q

Which bacterial plant disease is a gram-positive filamentous bacteria whose primary hosts are potato, sweet potato, beets, carrots and radishes? Its symptoms include corky surface lesions and root rot in sweet potatoes.

A

Common scab, pox - Streptomyces

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58
Q

Which mollicute plant disease has a primary host of palms, is phloem-limited and its vector is planthoppers? It is not cold-hardy and has had a recent northward spread.

A

Palm Lethal Yellowing - Candidatus Phytoplasma palmae

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59
Q

Which 9 bacteria are gram negative?

A

Erwinia, Pantoea, Xylophilus, Acidovorax, Burkholderia, Ralstonia, Pseudomonas, Xanthomonas, Agrobacterium

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60
Q

Which 4 bacteria are gram positive?

A

Clavibacter, bacillus, clostridium, streptomyces

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61
Q

Motile by single polar flagellum, no pigment produced on nutrient agar, grows at 40 degrees C. One species, A. citrulli, causes watermelon fruit blotch

A

Acidovorax

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62
Q

Motile by 1-6 peritrichous flagella, when growing on carbohydrate-enriched media, the bacteria produce copious extracellular polysaccharide slime. Colonies are non-pigmented to light beige. Induced plant diseases known as crown gall, hairy root, and cane gall

A

Agrobacterium

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63
Q

Motile with lophotrichous flagella, plant pathogenic bacteria with the exception of one species produce fluorescent pigments

A

Pseudomonas

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64
Q

Motile with polar flagella, no growth at 40 degrees C, forms two colony types on media amended with glucose; one is mucoid and the other is dry

A

Ralstonia

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65
Q

Motile with 1 polar flagellum. When growing on glucose-enriched media, the bacteria produces copious extracellular polysaccharide slime. Colonies are yellow, causes leaf spots and vascular wilts.

A

Xanthomonas

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66
Q

Non-motile bacterium; nutritionally fastidious requiring specialized medium such as glutamine peptone medium (PW); habitat is xylem of plant tissues

A

Xylella

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67
Q

Formerly Erwinia species; motile with peritrichous flagella; produce pectolytic enzymes that degrade pectate resulting in macerated plant tissue

A

Dickeya and Pectobacterium

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68
Q

Motile by peritrichous flagella; are non-pectolytic and the type strain E. amylovora causes fire blight

A

Erwinia

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69
Q

Motile by peritrichous flagella; non-pectolytic, most produce a yellow pigment; Stewart’s wilt of corn

A

Pantoea

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70
Q

Straight or slightly curved slender rod; irregular and often club-shaped; obligately aerobic, non-motile, bacterial canker of tomato. Gram +

A

Clavibacter

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71
Q

Vegetative hyphae produce extensive mycelium, aerial mycelium forms chains of spores, produce wide variety of pigments, many produce one or more antibiotics. Potato scab incited by S. scabies is most studied, produces a toxin that is a major virulence factor.

A

Streptomyces

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72
Q

What is a nucleic acid containing genes and a protein coat?

A

Virus

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73
Q

What is a circular dsDNA containing genes and no protein coat?

A

Plasmid

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74
Q

What is a small circular ssRNA with no genes and no protein coat?

A

Viroid

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75
Q

What is a nucleic acid (could have genes, could have protein coat) and requires a host virus?

A

Satellite

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76
Q

4 Examples of Mobile Genetic Elements

A

Plasmid
Virus
Viroid
Satellite

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77
Q

A mobile genetic element may consist of which two things?

A

Genes and protein coat

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78
Q

What 3 things do all mobile genetic elements have in common?

A

They act as obligate parasites
They replicate independently of the host genome
They can affect the host phenotype

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79
Q

What is the size in cubic nanometers of a large virus?

A

6x10^5

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80
Q

What is the size in cubic nanometers of a small virus?

A

2x10^4

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81
Q

Ten million particles of a small virus would occupy only ___% of the cell volume in a typical plant cell.

A

1%

82
Q

Which 3 scientists refuted spontaneous generation and show that bacteria and fungi can cause disease?

A

DeBary, Pasteur, & Koch

83
Q

Mayer, Ivanovsky, and Beijerinck described which disease?

A

Tobacco mosaic disease

84
Q

Which scientist showed that the infective agent could pass through agar and showed through serial dilutions that the agent was reproducing in the plant? He was also the first to use the term VIRUS

A

Martinus Beijerinck 1898

85
Q

What 6 characteristics are used to classify viruses?

A

Size, shape, coating type, number of particles, type of nucleic acid, and sequence

86
Q

What are two shapes of viruses?

A

helical and icosahedral

87
Q

How is the size of a helical-shaped virus described?

A

Length, width, and flexibility

88
Q

How is the size of an icosahedral-shaped virus described?

A

Diameter

89
Q

The average size of icosahedral viruses are mostly _____nm but can be up to _____nm in diameter.

A

20-30; 50-80

90
Q

What part of the virus is the protein coat and is usually made up of identical subunits?

A

Capsid

91
Q

What part of a virus is formed when the capsid subunits and the genome self-assemble?

A

Virion

92
Q

What may be composed of one or more virions?

A

Virus

93
Q

A virus particle; an entire virus particle, consisting of an outer protein shell called a capsid and an inner core of nucleic acid (either RNA or DNA); the mature virus particle with all its structural components intact

A

Virion

94
Q

4 Steps of TMV Assembly

A
  1. Coat protein units assemble into disk-shaped aggregates
  2. Aggregate binds to ‘origin-of-assembly’ loop in RNA
  3. Additional aggregates bind, pulling the RNA strand up through the hole in the center
  4. Assembly terminates when the end of the RNA is reached
95
Q

Icoashedral Virus Assembly….

A

Coat protein subunits with bound nucleic acid self-assemble.

96
Q

Nucleic acid enclosed within the capsid protein

A

Nucleocapsid

97
Q

Bilayer membrane, derived from the host cell membrane with viral proteins

A

Envelope

98
Q

Which ssRNA may be directly translated like mRNA?

A

Positive sense

99
Q

Which ssRNA requires conversion by RNA polymerase prior to translation?

A

Negative sense

100
Q

Which type of RNA virus cannot function as mRNA but must carry transcription enzymes and synthesize mRNAs?

A

dsRNA

101
Q

Which DNA virus enters the host nucleus and uses host enzymes for replication and transcription?

A

dsDNA

102
Q

Which DNA virus must use DNA polymerase to make a double stranded intermediate?

A

ssDNA

103
Q

What is the average number of genes in a plant virus?

A

4-12

104
Q

What are the minimum requirements for the structural proteins of a virus?

A

Capsid or nucelocapsid protein

105
Q

What are the minimum requirements for non-structural proteins of a virus?

A

Polymerase, movement

106
Q

What are the 4 steps of the virus infection process?

A
  1. Virions enter cell (Penetration)
  2. Virions uncoat (release nucleic acid)
  3. Replication and translation (Reproduction and infection)
  4. Movement (Colonization)
107
Q

What conditions are required for a virion to enter a cell?

A

Vector or wound

108
Q

How do viruses move through a host from cell to cell?

A

Altered plasmodesmata - they cannot move through normal plasmodesmata

109
Q

Which proteins allow cell-to-cell movement?

A

Movement proteins

110
Q

What are the two described methods of cell-to-cell movement through plasmodesmata?

A
  1. Increase size of plasmodesmata, bind to viral RNA and chaperone it through.
  2. Form tube through plasmodesmata and virions move through tube structures.
111
Q

What are 4 examples of how viruses can move between hosts?

A

Mechanical (wounding), vegetative (grafting, vegetative propagation), seed (vertical transmission), and vectors

112
Q

What form of transmission occurs when the sap of the infected plant contacts the wound?

A

Mechanical

113
Q

Which 3 viruses are spread via mechanical transmission?

A

Tobacco mosaic virus
Potato virus X
Cucumber mosaic virus

114
Q

What form of transmission occurs from budding, grafting, cutting, tubers, corms, rhizomes, and root grafts?

A

Vegetative

115
Q

Which virus is spread via vegetative transmission?

A

Tulip breaking virus

116
Q

Which form of transmission occurs through seeds, includes ~18% of plant viruses but still results in very high disease despite very low transmission?

A

Seed vertical transmission

117
Q

What is the most common viral transmission route?

A

Insect vectors

118
Q

5 examples of homoptera

A

Aphids, whiteflies, leafhoppers, planthoppers, mealy bugs

119
Q

Homoptera are (piercing-sucking/chewing).

A

Piercing-sucking

120
Q

4 examples of chewing bugs

A

Psyllids, thrips, beetles, grasshoppers

121
Q

Which insect-virus relationship has an ingestion time of 1-10 minutes, a retention time of 1-10 minutes, and the virus is associated with the stylet of the vector?

A

Non-circulative, non-persistent

122
Q

Which insect-virus relationship has an ingestion time of greater than or equal to 10 minutes, a retention time of 1-7 days, and the virus transmission is associated with the foregut of the vector?

A

Non-circulative, semi-persistent

123
Q

Which insect-virus relationship has an ingestion time of greater than or equal to 15 minutes, a retention period of 1 day - life, a latent period of 4-6 hours, and the virus is transported across the insect gut wall into the hemocoel then from the hemocoel to the salivary glands?

A

Circulative, non-propagative

124
Q

Which insect-virus relationship has an ingestion time of greater than or equal to 15 minutes, a retention period of 1 day - life, a latent period of 4-6 hours and the virus replicates within the insect’s cells?

A

Circulative propagative

125
Q

Which plant-viral interaction shows no viral replication or cell-to-cell movement?

A

Immunity

126
Q

Which plant-viral interaction shows the virus replicating and moving through the plant?

A

Symptoms

127
Q

Which plant-viral interaction is when the virus replicates and moves, but has no evident symptoms?

A

Tolerance

128
Q

Which plant-viral interaction is when the virus replicates, plant produces a hypersensitive response leading to programmed cell death?

A

Necrosis (HR)

129
Q

Which plant-viral interaction is when the virus replicates and moves, causes symptoms in new leaves, but symptoms disappear over time with further growth?

A

Recovery

130
Q

A polythetic class of viruses that constitutes a replicating lineage and occupies a particular ecological niche

A

Virus species

131
Q

What is the current criterion for defining a virus species?

A

Genome sequencing

132
Q

3 steps for naming a virus

A
  1. Common name of the host species in which it was first discovered
  2. Characteristic symptom in that host
  3. “Virus”
133
Q

What is the first named virus?

A

TMV

134
Q

What is the 4th step to naming a virus if a new virus is identifed in the same host with the same symptoms as an existing named virus?

A

Add discovery location after symptom

135
Q

Approved family, genus, and species names are written in _________.

A

Italics

136
Q

What has to happen for a virus name to be approved??

A

Genetic sequence

137
Q

What virus has a wide host range, mostly solanaceous, disseminates easily (exceptionally stable!) enters through wounds, and was the first virus identified and described?

A

TMV

138
Q

Which virus has symptoms of mosaic, spotting, streaking, stunting, vein-yellowing, malformation, yield reduction, and inclusion bodies?

A

TMV

139
Q

One virion is the virus, the entire virus is contained in one particle

A

Monopartite

140
Q

What is the largest plant virus genus? It is monopartite, flexuous, forms cylindrical, pinwheel inclusion bodies, and is aphid-transmitted? It is non-persistent and requires a helper protein

A

Potyviruses

141
Q

Why do potyviruses field incidences commonly reach 100%?

A

Because of the effectiveness of aphid transmission

142
Q

What potyvirus has a host range including stone fruits, ornamentals and other wild species? It has a long history in Europe, but was introduced into the US In 1999. Its impact includes yield losses and reduced marketability.

A

Plum Pox Virus (PPV)

143
Q

How is plum pox virus contained?

A

Infected trees are removed and destroyed

144
Q

What potyvirus includes hosts of papaya and other cucurbits? Its impacts includes young trees being stunted and not producing fruit and older trees producing small, spotted unpalatable fruit.

A

Papaya Ring Spot Virus

145
Q

What potyvirus is a thread-like virus whose primary hosts are citrus fruit (oranges, grapefruit, lime and sour orange rootstock)? It is disseminated by aphids (semi-persistent), budding or grafting and impacts fruit quantity and quality ultimately leading to tree decline and death.

A

Citrus tristeza

146
Q

What is the most effective vector of Citrus Tristeza?

A

Brown citrus aphid

147
Q

What tospovirus affects more than 500 species of hosts and is disseminated by 9+ species of thrips with an infection rate of 50-90%?

A

Tomato spotted wilt

148
Q

How do thrips transmit tomato spotted wilt?

A

Acquired by larvae and transmitted by adults for life

149
Q

Which virus is a geminiviridae whose primary host is legumes? It is disseminated by whiteflies (semi-persistent) and causes up to 100% yield loss due to failure to flower.

A

Bean Golden Mosaic Virus

150
Q

What are the 3 characteristics in the body plan of a nematode?

A

Digestive tract with excretory system
Nervous system
Sexual reproductive system

151
Q

Which two things does a nematode NOT have in its body plan?

A

Circulatory system

Respiratory system

152
Q

What is the size range of a nematode?

A

0.3mm-8m

153
Q

What are the 4 lifestyles of nematodes?

A

Bacterial feeders
Fungal feeders
Predators
Parasites

154
Q

What features allow us to distinguish different species of nematodes?

A

Size and shape (length/width and dimorphism), cuticle (+/- annulations), mouth parts (stylet), esophagus parts, reproductive parts

155
Q

What must a nematode have in order to be a plant pathogen?

A

Stylet

156
Q

3 types of stylets

A

Stomatostylet (dagger)
Odontostylet (sword with hand guard)
Onchiostylet (hook)

157
Q

Which stylet has various lengths, is needle-like, and has 3 knobs at its base?

A

Stomatostylet

158
Q

Which stylet is spear-like, hollow, has flanges at the base, and consists of a stylet, stylet extension, and a guide ring?

A

Odontostylet

159
Q

Which stylet is blade-like, solid, curved, with no flanges or knobs? This is the least common type of stylet.

A

Onchiostylet

160
Q

What is the difference between a 2 part esophagus and a 3 part esophagus?

A

The 3 part has a median bulb

161
Q

One ovary

A

monodelphic

162
Q

Two ovaries

A

didelphic

163
Q

Ovary positions in both directions

A

amphidelphic

164
Q

Ovary position anterior of vulva

A

prodelphic

165
Q

Male reproductive parts (2)

A

spicules and bursa

166
Q

Extra flap of cuticle in male nematodes which may or may not be present.

A

bursa

167
Q

The first molt of a nematode occurs where?

A

Inside the egg

168
Q

Which stage of the nematode life cycle is when it hatches and finds a plant fo infect?

A

2nd stage juvenile

169
Q

What is the dormant survival stage in some nematodes?

A

Quiescent state

170
Q

Which nematode-plant interaction includes a nematode who lives outside the root and feeds on epidermal cells?

A

Ectoparasites

171
Q

Which nematode-plant interaction includes a nematode who enters the plant root and feeds from within?

A

Endoparasites

172
Q

Which nematode-plant interaction includes a nematode whose head is in and tail is out of the root?

A

Semi-endoparasites

173
Q

Which nematode-plant interaction includes a nematode who moves from cell to cell?

A

Migratory

174
Q

Which nematode-plant interaction includes a nematode who establishes a feeding site and remains there?

A

Sedentary

175
Q

When talking about sedentary versus migratory nematodes, we are only talking about _____ _______ because _____ and _____ move.

A

Adult females; juveniles; males

176
Q

What is the most common type of nematode that feeds primarily on epidermal cells?

A

Migratory ectoparasite

177
Q

What are 5 examples of migratory ectoparasites?

A

Sting, dagger, stunt, ring, stubby-root

178
Q

What type of nematode feeds on cortical cells?

A

Migratory endoparasite

179
Q

What are 3 examples of migratory endoparasites?

A

Lesion, burrowing, lance

180
Q

What are 3 examples of above-ground migratory endoparasites?

A

Foliar, wheat gall, stem & bulb

181
Q

What type of migratory endoparasite migrates within the plant stem/trunk, invades larvae of insect vector, and remains dormant until the insect matures and moves to the new host?

A

Insect-vectored vascular nematodes

182
Q

What type of nematode is the most clearly pathogenic, host specific with complicated host relationships? It is a female establishing a specialized feeding site.

A

Sedentary endoparasite

183
Q

What are 3 examples of sedentary endoparasites?

A

Root-knot, cyst, citrus

184
Q

What type of nematode is a female establishing a specialized feeding site, but only part of the body is within the root?

A

Sedentary semi-endoparasite

185
Q

What are 2 examples of sedentary semi-endoparasites?

A

Reniform and citrus

186
Q

What type of plant damage to pathogenic nematodes cause

A

Cell death, lesions, galls, excessive lateral roots

187
Q

The majority of pathogenic nematodes are _____ feeders.

A

Root

188
Q

What above-ground symptoms appear in plants affected by pathogenic nematodes?

A

Water and nutrient deficiency, poor stand development

189
Q

What diseases do nematodes serve as a vector for?

A

Viruses; nepoviruses and tobraviruses

190
Q

Which nematode has over 3000 hosts, distributed worldwide in warm climates and impacts 5% of world production lost every year?

A

Meloidogyne - Root knot nematode

191
Q

What kind of lifestyle does the root knot (meloidogyne) nematode have?

A

Sedentary endoparasite

192
Q

What kind of stylet does the meloidogyne (root knot) nematode have?

A

Stomatostylet

193
Q

Does the meloidogyne (root knot) nematode have a median bulb?

A

Yes

194
Q

How do we differentiate species of meloidogyne?

A

Perineal patterns on females

195
Q

What are 2 examples of cyst nematodes?

A

Heterodera (Soybean cyst) and Globodera (Potato Cyst - Golden)

196
Q

What is the lifestyle of the cyst nematodes?

A

Sedentary endoparasite

197
Q

What nematode has over 400 host plant species (monocots and dicots), is distributed worldwide in both tropical and temperate climates and is 3rd ranked for crop losses?

A

Lesion nematodes - Pratylenchus

198
Q

What is the lifestyle of the lesion nematodes (pratylenchus)?

A

Migratory endoparasite

199
Q

What nematode has over 700 host plant species and has 3 species that are distributed worldwide in both tropical and temperate climates?

A

Foliar nematodes - Aphelenchoides

200
Q

What is the lifestyle of the foliar nematodes (aphelenchoides)?

A

Migratory endoparasite

201
Q

What nematode has many hosts and is distributed through sandy soils? It is native to SE USA but has been introduced to Australia, the Caribbean, Bermuda, and California.

A

Sting nematode (Belonolaimus)

202
Q

What is the lifestyle of the sting nematode (Belonolaimus)?

A

Migratory ectoparasite

Plant Pathology (5 decks)

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