Insect-Plant Relations

Question 1

Describe the “evolutionary arms race” between plants and herbivores.

Answer 1

Question 2

Describe the pyramid of trophic levels, including general groups of organisms that occupy each position.

Answer 2

Natural enemies are organisms that kill, decrease the reproductive potential of, or otherwise reduce the numbers of another organism. Natural enemies that limit pests are key components of integrated pest management programs.

Question 3

What are volatile compounds and what role might they play in predator-prey relations between insects?

Answer 3

Question 4

In what 3 ways can plants respond to herbivory?

Answer 4

Antixenosis
Antibiosis
Tolerance

Question 5

What is antixenosis?
What are 2 forms of it?
How is it measured?

Answer 5

Question 6

What is antibiosis?
What 2 strategies enable this?

Answer 6

remember alkaloids are N-based

Question 7

What is tolerance and what are 2 common strategies for it?

Answer 7

Question 8

What types of physical leaf characteristics might deter herbivory?

4

Answer 8

Question 9

What type of physical stem characteristics might deter hebivory?

2.3

Answer 9

Question 10

Describe insect responses to plant physical defenses

mouthparts
timing
behavior

Answer 10

Question 11

What is often special about leaf veins with regards to herbivory?

Answer 11

Question 12

How might plants adjust their phenology to minimize herbivory?

5

Answer 12

Question 13

Describe insects counter-responses to plants phenological defenses

behavior
timing
reproduction

Answer 13

Question 14

Describe diapause, using the pecan weevil as an example

Answer 14

this ensures there will always be generations of weevils emerging in all years, since trees may not produce nuts in some years

Question 15

What are some plant chemical properties that may deter herbivory?

2.3.1

Answer 15

Question 16

What is the difference between constitutive and induced allelochemicals?
What are some examples of each?

Answer 16

Question 17

Describe different induced allelochemical responses with regard to timing, and their subsequent effects.

Answer 17

Question 18

How does insect herbivory affect future insect herbivory?

Answer 18

Question 19

What kinds of counter-responses might insects evolve to deal with plant chemical defenses?

Answer 19

Question 20

relate these factors to the effects of herbivory

deciduous vs coniferous
early vs. late
tissue location/age
extent
re-flushing

Answer 20

Question 21

How does plant stress affect a tree’s response to defoliation?

resistance, tolerance, populations

Answer 21

Question 22

Describe some inter-guild competition effects of herbivory

folivores
root insects/pathogens
bark beetles

Answer 22