Associate Certified Entomologist (ACE) Practice Exam

Which species are the sources of the most widely used botanical insecticide, pyrethrins?

1. Chrysanthemum morifolium and Chrysanthemum cinerariifolium

2. Chrysanthemum cinerariifolium and Chrysanthemum coccineum

3. Chrysanthemum maximum and Chrysanthemum angustifolium

4. Chrysanthemum roseum and Chrysanthemum simplicifolium

The correct answer is: Chrysanthemum cinerariifolium and Chrysanthemum coccineum

The most widely used botanical insecticide, pyrethrins, is derived from the flowers of specific species of the Chrysanthemum genus. Chrysanthemum cinerariifolium is particularly notable, as it is the primary source of pyrethrins. The second species mentioned, Chrysanthemum coccineum, contributes to the characteristics and potency of the insecticide. Pyrethrins are known for their effectiveness in controlling a variety of pests while being less toxic to mammals, which is why they are a popular choice in both agricultural and residential settings. The compounds found in these specific species of chrysanthemums disrupt the normal functioning of an insect's nervous system, leading to paralysis and death. The extraction process from these plants captures the essential oils that contain the active pyrethrins. The other options do not represent the correct species that yield pyrethrins. For instance, while there are many different Chrysanthemum species, they do not all produce the same insecticidal compounds found in Cinerariifolium and Coccineum. Understanding the source of these botanical insecticides is crucial for their proper application in pest management strategies, particularly in sustainable practices.