Final answer:
The symptoms of extensive damage to the corn ear, tunneling in the stalk, root system damage, and leaves that have been holed and laced can be attributed to the pests Helicoverpa zea, Papaipema nebris, Diabrotica virgifera, and Pseudaletia unipuncta, respectively.
Step-by-step explanation:
Matching the symptom to the corn pest that causes it:
Extensive damage to ear: Helicoverpa zea (Corn earworm)
Tunneling damage to stalk: Papaipema nebris (Stalk borer)
Damage to root system, weak plants: Diabrotica virgifera (Western corn rootworm)
Leaves have been holed and laced: Pseudaletia unipuncta (True armyworm)
- These pests each target different parts of the corn plant and can cause significant damage to the crop, affecting both the yield and quality.