In greenhouse pest management, what action helps preserve pesticide effectiveness?

• A. Rotate pesticides to prevent resistance
• B. Use the same product repeatedly
• C. Increase spray volume without monitoring
• D. Ignore pest monitoring

Answer: (B)

Rotating pesticides with different modes of action helps preserve pesticide effectiveness by delaying the development of resistance. When the same product or the same mode of action is used repeatedly, pest populations experience constant selection pressure, and individuals with resistance survive and reproduce, making the product less effective over time. By switching to products that work differently, you reduce this selective pressure and keep each product effective longer, which is a core part of resistance management in integrated pest management.

Using the same product repeatedly accelerates resistance, increasing the risk that pests become immune to that product. Increasing spray volume without monitoring wastes chemicals and can harm plants or the environment without improving control if resistance is present. Ignoring pest monitoring leads to mistimed or unnecessary applications, wasting products and promoting resistance and crop damage.