CPA - Certified Pesticide Applicator Pesticide Resistance Management Questions and Answers Flashcards

Pesticide resistance is BEST defined as:

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.

Which pest management practice is MOST effective at slowing the development of pesticide resistance?

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.

What is a 'mode of action' (MOA) in pesticide terminology?

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.

Which of the following is a sign that a pest population may have developed resistance to a pesticide?

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.

IRAC (Insecticide Resistance Action Committee) group numbers on pesticide labels help applicators:

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.

Cross-resistance in pest management means that a pest resistant to one pesticide:

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.