CPA CPA - Certified Pesticide Applicator Pesticide Resistance Management Questions and Answers 1 — Questions and Answers
Question 1: Pesticide resistance is BEST defined as:
- A pest's temporary avoidance of a treated area
- A heritable trait in a pest population that reduces the effectiveness of a pesticide (Correct answer)
- The chemical breakdown of a pesticide in the environment
- A regulatory limit on how often a pesticide can be applied
Correct answer: A heritable trait in a pest population that reduces the effectiveness of a pesticide
Resistance is a genetic, heritable change in a pest population that makes individuals survive exposures that would kill susceptible individuals.
Question 2: Which pest management practice is MOST effective at slowing the development of pesticide resistance?
- Increasing the pesticide application rate each season
- Rotating pesticide mode-of-action (MOA) classes (Correct answer)
- Applying the same pesticide product repeatedly each year
- Using only one pesticide class throughout the entire growing season
Correct answer: Rotating pesticide mode-of-action (MOA) classes
Rotating between pesticides with different modes of action prevents continuous selection pressure on any single mechanism, slowing resistance development.
Question 3: What is a 'mode of action' (MOA) in pesticide terminology?
- The physical form in which a pesticide is applied
- The specific biochemical or physiological process in a pest that a pesticide disrupts (Correct answer)
- The geographic area where a pesticide is registered for use
- The speed at which a pesticide degrades in soil
Correct answer: The specific biochemical or physiological process in a pest that a pesticide disrupts
Mode of action describes the specific biological target or mechanism—such as acetylcholinesterase inhibition—by which a pesticide kills or controls a pest.
Question 4: Which of the following is a sign that a pest population may have developed resistance to a pesticide?
- Pests avoid the treated area entirely before dying
- Pest populations are controlled at lower-than-label rates
- Normal application rates fail to provide expected levels of control over time (Correct answer)
- Pests reproduce more slowly after treatment
Correct answer: Normal application rates fail to provide expected levels of control over time
When labeled rates that previously worked begin to fail repeatedly and consistently, resistance in the population is a likely explanation.
Question 5: IRAC (Insecticide Resistance Action Committee) group numbers on pesticide labels help applicators:
- Determine the legal re-entry interval for workers
- Identify the mode of action and rotate between different groups to manage resistance (Correct answer)
- Calculate the correct application rate per acre
- Understand the environmental fate of the product
Correct answer: Identify the mode of action and rotate between different groups to manage resistance
IRAC numbers classify insecticides by mode of action so applicators can deliberately rotate between groups and avoid selecting for cross-resistance.
Question 6: Cross-resistance in pest management means that a pest resistant to one pesticide:
- Can be controlled by increasing the dose of that pesticide
- May also be resistant to other pesticides that share the same mode of action (Correct answer)
- Will lose resistance if left untreated for one season
- Becomes susceptible to pesticides from a completely different class
Correct answer: May also be resistant to other pesticides that share the same mode of action
Cross-resistance occurs when the same genetic mechanism that confers resistance to one compound also reduces susceptibility to chemically related or mechanistically similar compounds.
CPA CPA - Certified Pesticide Applicator Pesticide Resistance Management Questions and Answers 1
Pesticide resistance is BEST defined as: