The characteristic ‘fox odour’ of the Crown imperial fritillary, which is said to keep moles away, is caused by a single volatile substance, not a blend of more components, produced by the plant. This is the conclusion of research carried out at Plant Research International, an institute of Wageningen UR. The study was published in the scientific periodical Journal of Agricultural and Food Chemistry.
The Crown imperial has been known to repel moles from gardens for a long time. This has led the plant to be grown for reasons beyond its pretty flowers. They are often placed at the edge of gardens for maximum repellence efficacy.
The Wageningen researchers discovered that the fox odour of the bulbs, which is also released by the rest of the above-ground parts of the plant, is caused by a single substance. With the help of a combination of human olfactory capacities and high-tech analytical equipment (GCMS), they also discovered the structure of the substance, which turned out to be a sulphurous terpene. The scientists subsequently managed to reproduce it exactly using organic chemical synthesis in the laboratory.
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