Associate Certified Entomologist (ACE) Practice Exam

Which insect has never developed resistance to malathion?

1. The boll weevil

2. The cabbage worm

3. The diamondback moth

4. The aphid

The correct answer is: The boll weevil

The boll weevil is recognized for having not developed resistance to malathion, making it the correct answer. Malathion is an organophosphate insecticide widely used in agriculture, particularly effective against pests like the boll weevil. The boll weevil itself has been subject to various control strategies over the years, but it has not shown the capacity to develop resistance to malathion, which is significant for pest management. In contrast, other insects listed have shown some level of resistance to malathion. For instance, the cabbage worm, the diamondback moth, and various aphids have developed resistance mechanisms that allow them to survive applications of malathion. Consequently, understanding the resistance patterns of different pests is critical in agricultural management to ensure the continued effectiveness of insecticides like malathion.