Which of the following is a pheromone-based method to manage grape moths?

• A. The bacterium Bacillus thuringiensis (which produces substances that are toxic to the moths)
• B. Natural predators (parasitic wasps, green lacewings, some spider species)
• C. Insecticides
• D. Use of pheromone capsules to disrupt mating

Answer: (D)

The main concept here is mating disruption using pheromones. In grape moth management, pheromone capsules release synthetic sex pheromones into the vineyard, creating a confusing environment for male moths. With these pheromone plumes everywhere, males have trouble locating females, so mating success drops and far fewer eggs are laid. This reduces pest pressure without killing insects directly, and it’s highly specific to the target species, helping preserve beneficial insects and minimizing chemical residues. The other approaches don’t use pheromones to interrupt mating: Bacillus thuringiensis works by toxins that affect larvae after ingestion; natural predators provide biological control but don’t disrupt mating; and insecticides kill or repel pests but aren’t pheromone-based.