Friday, 6 March 2009

The discovery of a family of compounds that stimulates seed germination in many plants has led to a new scientific name – karrikins – derived from the Noongar word ‘karrik’, meaning ‘smoke’.

Western Australia is home of the discovery of a substance in smoke that stimulates seed germination and seedling growth in many plant species after bushfires.

Now, new research at UWA and Kings Park Botanic Garden has now shown that there are several such compounds in smoke, and that they can even stimulate seed germination in plant species that do not normally experience fire or smoke. This family of germination stimulants has now been named ‘karrikins’ from ‘karrik’, a Noongar word for smoke.

The new research from the UWA team has just been announced in the prestigious journal Plant Physiology, published by the American Society of Plant Biologists. The research shows that Arabidopsis thaliana, a species of cress from the temperate northern hemisphere responds to karrikins.

Arabidopsis is the ‘lab rat’ of the plant world that will now allow the mechanism of karrikin action to be uncovered. The significance of this research is shown by the decision of the editors to showcase karrikins on the front cover of the journal – a beautiful image showing a range of seeds from smoke-responsive Western Australian species.

But why the name ‘karrikin’?
The original substance, discovered by Dr Gavin Flematti of Chemistry at UWA, has a very complex chemical name and belongs to a large chemical group called ‘butenolides’.

“We needed a simple name to refer to the specific butenolides that stimulate seed germination,” says Dr David Nelson, a member of the UWA research team. Dr Nelson consulted Alan Dench, Professor of Linguistics at UWA, who advised that the first recorded Noongar word for 'smoke' from the Perth area in the 1830s, is 'karrik'.
This provided the perfect stem from which to create a new name. In keeping with convention in naming families of biologically active molecules, the –in suffix was added to give us ‘karrikin’.

It’s not the first time a Noongar word has been adopted for use in English. The Noongar word ‘kylie’, a type of boomerang, is now a common name in the English language.

Professor Kingsley Dixon, who leads the team at Kings Park, says the newly coined word is appropriate recognition. “This new name recognises that the scientific discovery was made on Noongar land, and it reflects the importance of fire and smoke to plant ecology and to Aboriginal culture,” he says.

With its publication, the term karrikin is now set to become adopted in scientific language and to take its place in plant biology textbooks alongside auxin and phytoalexin as a fundamentally important plant growth regulator

Media references

To read the journal article, follow the link:

Professor Steven Smith (+61 8) 6488 4403
Professor Kingsley Dixon (+61 8) 9480 3637


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