Bacillus thuringiensis (Bt) is used for control of which pests?

Bacillus thuringiensis (Bt) is used for control of which pests?

• A. Aphids
• B. Grubs
• C. Nematodes
• D. Caterpillars

Answer: (D)

Bt is a biological pesticide whose toxins must be ingested by susceptible insects. In turf, the most relevant target is caterpillars (Lepidoptera larvae) because the Cry toxins produced by Bacillus thuringiensis disrupt the caterpillar’s gut after they eat treated material, leading to death. This mode of action makes Bt effective for caterpillars like armyworms and cutworms, while not effectively controlling aphids (sap-sucking insects), nematodes (soil-dwelling worms), or beetle larvae commonly called grubs. Some Bt strains exist for beetles, but the formulations most used in turf are aimed at caterpillars, which is why caterpillars are the best answer.

Bt is a biological pesticide whose toxins must be ingested by susceptible insects. In turf, the most relevant target is caterpillars (Lepidoptera larvae) because the Cry toxins produced by Bacillus thuringiensis disrupt the caterpillar’s gut after they eat treated material, leading to death. This mode of action makes Bt effective for caterpillars like armyworms and cutworms, while not effectively controlling aphids (sap-sucking insects), nematodes (soil-dwelling worms), or beetle larvae commonly called grubs. Some Bt strains exist for beetles, but the formulations most used in turf are aimed at caterpillars, which is why caterpillars are the best answer.