Where Do Flowers Get Their Smell From?
Most flowers get their smell from oil produced in their petals. As the oil evaporates into the air, we are able to smell the fragrance it gives off. While the scents of such flowers as roses and violets are pleasant to sniff, they are important to the flower, too. The flower’s fragrance attracts bees and some other insects, which help in the important work of pollination.
Not all flowers are pleasing to smell. Flowers that attract flies smell like rotting meat. One of the world’s rarest, largest, smelliest, and strangest looking flowers is the titan arum, or the corpse flower.
It is called the corpse flower because it smells like rotting meat. The bloom is over 8 foot tall and 12 feet in circumference. They smell like rotting flesh in order to attract flies, their preferred pollinator.
People have been known to pass out from the smell! Flowers that are pollinated by the wind have no smell at all, because these flowers do not need to attract insects.
Now, scientists have pinpointed exactly how the flower produces their sweet aroma by identifying the gene that ‘switches on’ the scent. And they hope the development may allow gardeners to cultivate blooms that look good and smell good – by making sure the gene is present in any new varieties of rose.
The team made their discovery by comparing two roses – Papa Meilland, which has a strong fragrance, and Rouge Meilland, which has very little scent. They identified a gene that ‘switches on’ a crucial enzyme called RhNUDX1. The chemical acts in the cells of the flower’s petals to generate a chemical called monoterpene geraniol, one of the sweetest-smelling parts of rose oil.
Wild roses could not survive without this scent, as it attracts bees to pollinate its flower. But over the years, roses, particularly those for the cut flower market, have mostly been bred for their appearance – and many have lost their scent.
Because the flowers often have to travel hundreds of miles to reach the shops, their toughness has also been valued more than their fragrance. As a result, the scent of roses has suffered, and become something of an afterthought.
Researcher Philippe Hugueny, whose work was published in the journal Science, explained: ‘In cultivated roses, the scent has no reproductive function; it’s only for our pleasure. So if roses lose their scent it’s too bad. But if a wild rose lost its smell it would die out.’ He added: ‘We discovered roses use a special pathway to make monoterpenes which has not been shown in other plants.’
Mr Hugueny, of the French National Institute for Agricultural Research, said the find may help develop roses that look and smell good. While there is currently no demand for genetically modified roses in Europe, Mr Hugueny said that in Japan, where breeders have experimented with creating modifications including blue roses, the research might be considered useful.