CDFA Pest Prevention Plant Regulation Practice Exam

What is a common symptom of a sweet potato weevil infestation?

1. Wilting leaves

2. Scarring on the tubers

3. Leaf discoloration

4. Rapid growth

The correct answer is: Scarring on the tubers

A common symptom of a sweet potato weevil infestation is scarring on the tubers. This occurs because sweet potato weevils are known to bore into the stored tubers, laying their eggs and feeding on the plant material. As they tunnel through the sweet potatoes, they create noticeable scars and holes on the surface. This scarring can lead to decay and can affect the overall quality and marketability of the tubers. Wilting leaves, leaf discoloration, and rapid growth are often associated with other pests or diseases but are not specific indicators of sweet potato weevil presence. Wilting leaves may arise from various stress factors, such as disease or insufficient water, while leaf discoloration could indicate nutrient deficiencies or other issues. Rapid growth is not a symptom of infestation; in fact, infested plants may exhibit stunted growth due to the stress caused by pests feeding on the roots. Thus, the presence of scarring clearly points towards a sweet potato weevil infestation.