Maybe I‘m easily amused. Particularly by the sight
of folks, at local flower shows, who can be seen stooping - to
sniff at dahlia blooms. Some move on along the bench, convinced
the flowers are artificial.
Their confusion soon could end. Scientists, already know how
to identify and implant colour genes. Now they have moved on
- to manipulate the genes that produce actual scents.
This latest research paves the way to producing flowers with individual,
designer created scents. A chrysanth smelling of violets. A
dahlia smelling of vanilla. Whatever the customer wants.
It provides the prospect, for example, of some future dahlia variety,
which could be both blue in colour and scented to order.
Natalia Dudareva, heading a research programme at a US university,
claims to have found how plants and indeed individual varieties
produce distinctive scents. The actual smell comes from essential
oils that evaporate in warm weather. The oils emanate from volatile
compounds contained in the plant‘s genetic make up.
The number and level of such compounds varies dramatically and
is dependent on the species. Some types of orchids, for example,
have a complex make up and contain over 100 different compounds.
Obviously there are precious few in the dahlia, or at least none
that are detectable to the human nose.
The Russian born scientist suspects the European gardening fashions
of the last 250 years may be responsible for the diminished aromas
of many species.
Breeders concentrated on size, colour, stems and shelf life.
Subtle scents were of low priority and, indeed, may have become
diminished or even bred out in the selection process.
It is no small wonder then that the world‘s perfume manufacturers,
plus other specialist commercial interests, are keeping track
on her findings. It opens the gateway for a range of new aromas
that are cheaper to produce.
Deploying genetics, the professor reckons that individual scents
can be enhanced or modified. Eventually they could be introduced
into an existing species. Varieties could easily be modified
genetically to “fix” new scents into succeeding generations.
“Every plant has its own unique scent signature”, she
says. We are only just beginning to work out what they are. Once
we know that, we can look for the genetic codes that trigger scent
production and work out exactly what is going on!”
Prof. Dudareva has been on the trail of plant scents for six years
and during a spell at the University of Michigan, set up the world‘s
first research laboratory. Her latest research programme is based
at a university in Indiana.
Analysing a scent is a slow process. The flower is sealed in
a plastic bag and the scent is then distilled. A “mass spectrometer”
is then used to identify the individual compounds and their particular
fragrance.
It opens the way to creating plants with a scent and colour to
order. The bride of the future could order her bouquet in specific
shades to tone with her dress - and emitting her favourite perfume.
All this mind boggling stuff will worry many traditionalists
and make growers wonder “What next?”. The answer
is - a lot. For example, boffins elsewhere are busy playing
about with genes from fireflies and phosphorescent jelly fish.
Implanted into Christmas trees, the pine needles would glow in
the dark thus eliminating the need to fiddle about each year with
fairy lights.
There is one small consolation. At least, Prof. Dudareva‘s
research has other spin offs, offering more practical benefits.
The smell could be manipulated to make a particular plant more
attractive to natural pollinators, thus boosting crop productivity.
Or used to create a natural scent that deters pests and predators.
That blue dahlia of the future, with its exquisite perfume, might
be doubly blessed - by never being bothered by greenfly.