3.2.9 The Role of Aphids in Spreading Plant Viruses Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Describe the structure of plant viruses

A

Consist of nucleic acid and protein coat & sometimes outer membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How can plant viruses enter plants?

A

Only through damaged sites or by using vectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Once inside the plant, what can viruses do (i.e. related to spreading/transmission)?

A

Can spread throughout plant & can be transmitted to next generation through seeds and vegetative reproductive structures (e.g. tubers)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Name 2 symptoms plant virus diseases

A
  • Yellowing in leaves
    • (known as chlorosis)
  • Distortion of parts of plant
    • e.g. leaf roll, malformation of flower and fruit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do plant virus diseases do to plants and what does this lead to (economically)?

A
  • Decreases photosynthetic efficiency
    • Reduces no. of grains and size of grain = loss of yield
  • Decreases value of crops
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the lifecycle of an aphid in the spring & summer

A
  • Clone themselves
    • Produce genetically identical daughter
    • Asexual reproduction
  • Half the clones born with wings to migrate to start colonies on a new host plant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the lifecycle of an aphid in the autumn & winter

A
  • Produce males and females to increase genetic variation
    • Sexual reproduction
  • Need huge stock of embryos that genetically different to increase chance of survival
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does an aphid’s stylet consist of?

A

Saliva canal and feeding canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens to the stylet as it penetrates the tissues to reach the phloem?

A

Saliva gels around it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe how aphids feed

A
  1. Insert their stylet (mouthparts) into phloem
  2. Phloem vessel is punctured, sap which is under high pressure = forced into aphid’s gut
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Name 3 ways how aphids reduce yields of crops

A
  • Remove phloem sap
    • Deprives plant of sugars and amino acids
  • Encourage growth of moulds on leaves
    • Reduces photosynthesis
  • Transmitting plant viruses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why can plant viruses only enter plant cells if they’re damaged?

A

Plant cell walls are too thick to enter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly