CDFA Pest Prevention Plant Regulation Practice Exam

How does the plum curculio overwinter?

1. Egg stage

2. Larval stage

3. Pupal stage

4. Adult stage

The correct answer is: Adult stage

The plum curculio, a significant pest of fruit crops, primarily overwinters in the adult stage. As adults, these insects enter a state of dormancy during the colder months, which allows them to survive freezing temperatures. They seek refuge in protected areas such as leaf litter, soil, or under debris, where they can remain safe from harsh winter conditions. This overwintering strategy is crucial for the population's resilience and is a key factor in their life cycle. By emerging in the spring, the adults can begin feeding on buds and flowers, laying eggs in fruit, and ultimately contributing to the next generation of curculios. Recognizing this behavior is essential for effective pest management and control strategies during the growing season. The other stages of the plum curculio—egg, larval, and pupal—do not contribute to their overwintering as effectively as the adult stage. Eggs and larvae are more vulnerable to environmental conditions, and pupae typically do not survive the winter outside of the protection afforded by adults in their dormant state. Understanding this aspect of the plum curculio's life cycle helps in implementing targeted pest prevention practices.