VL 11

Question 1

What is ecological backlash?

Answer 1

counter response of pest populations that diminish the impact of pest management tactics

• programs either gradually or abruptly lose effectiveness
• it can manifest in many ways (e.g. population rebound or pest switch)
• generally based on predictable population phenomena and insect physiology

Question 2

3 R’s of ecological backlash

Answer 2

Resistance: susceptibility of a pest to a control tactic changes

Resurgence: Pest population rebounds to a higher level than before the control tactic was applied

Replacement: Target pest is replaced by a new pest of previously minor status

Question 3

Monogenic resistance

Answer 3

obtained through expression of a single gene. Resistance can develop quickly. Example: House fly, developed DDT resistance within 2 years

Question 4

Polygenic resistance

Answer 4

many genes working together confer resistance. Development is slower and can be lost faster