CDFA Pest Prevention Plant Regulation Practice Exam

What type of plant is NOT attacked by the sweet potato weevil?

1. Sweet potato tubers

2. Irish potato plants

3. Morning Glory plants

4. Sweet potato plants

The correct answer is: Irish potato plants

The sweet potato weevil primarily targets plants within the morning glory family, particularly sweet potato plants and their tubers. When considering the options, Irish potato plants are botanically distinct from sweet potatoes and belong to the nightshade family, making them less susceptible to the sweet potato weevil's infestation, which is specifically adapted to the characteristics of sweet potatoes and related species. The sweet potato weevil has evolved to utilize sweet potato plants as a host, leading to damage from larvae feeding on the tubers. However, since Irish potato plants do not share the same botanical lineage and structural traits that the sweet potato weevil exploits, they are not typically attacked. Thus, identifying Irish potato plants as the correct answer aligns with the understanding that the sweet potato weevil has a limited range of host plants, primarily focused on sweet potatoes and related vegetation.