Why cornflower blue is like a red, red rose

Roses are red, cornflowers are blue - and for almost a century scientists have struggled to work out why.

Although the flowers have strikingly different colours, they share the same pigment, the reason for which has baffled botanists since 1913.

The anthocyanin pigment was first detected in the blue cornflower 92 years ago,and later the same pigment was found in a red rose, leading to the mystery of how one pigment could produce two colours.

Various theories abounded. Perhaps the cells of one flower had a different pH - acidity was known to affect flower colour - or perhaps it was due to differences in metal ions taken up from the soil.

Now a team of scientists from Japan, led by Masaaki Shiono of Kyushu University, reveal in the journal Nature that the answer lies in the way the pigment forms an unusual "supermolecule" in the cells of the cornflower plant.

While being of scientific interest, the development will be followed closely by commercial flower growers who are spending huge sums on trying to nurture blue flowers from plants that do not naturally produce blooms of that colour.

The most famous example is the search to produce a true blue rose. So far the attempt has centred on breeding a rose that produces a blue pigment called delphinidin, which is found naturally in delphiniums, but never in roses.

The scientists in Japan discovered that the pigment in cornflowers forms a giant molecular complex consisting of six molecules of anthocyanin bound to another pigment called flavone, along with four metallic ions - one iron, one magnesium and two calciums. But in roses, the same supermolecule does not appear to form, which could account for why the same pigment can cause different colours in the two flowers, the scientists say. Cathie Martin, professor of biology at the John Innes Institute in Norwich, said that the Japanese study broke the rule that to get a blue flower you needed to add the delphinidin pigment. "People have been trying to turn certain flowers blue, such as carnations, roses and chrysanthemums. The idea was that blue could only be conferred by the delphinidin pigment. It has been the dogma for years," Professor Martin said.

"This study is not saying that the idea is wrong, it's just that there now seems to be another way to make blue flowers and the point about cornflower blue is that it is a true blue and exceptionally beautiful," she said.

Discovering how a pigment found in red roses can be a brilliant sky blue in the cornflower could alter the breeding strategies aimed at creating blue roses. "The basic chemistry of the pigment molecule is the same in both cornflowers and roses. It's the way it's organised in its chemical superstructure that is different," Professor Martin said.

Start your day with The Independent, sign up for daily news emails
ebooks
ebooksAn introduction to the ground rules of British democracy
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Home Care / Support Workers

£7 - £10 per hour: Recruitment Genius: This care provider is looking for Home ...

Recruitment Genius: Web Team Leader

£30000 - £35000 per annum: Recruitment Genius: One of the UK's leading web des...

Recruitment Genius: Client Manager

£27000 - £35000 per annum: Recruitment Genius: A growing, successful, friendly...

Recruitment Genius: Property Negotiator - OTE £20,000+

£16000 - £25000 per annum: Recruitment Genius: This family owned, independent ...

Day In a Page

The Greek referendum exposes a gaping hole at the heart of the European Union – its distinct lack of any genuine popular legitimacy

Gaping hole at the heart of the European Union

Treatment of Greece has shown up a lack of genuine legitimacy
Number of young homeless in Britain 'more than three times the official figures'

'Everything changed when I went to the hostel'

Number of young homeless people in Britain is 'more than three times the official figures'
Compton Cricket Club

Compton Cricket Club

Portraits of LA cricketers from notorious suburb to be displayed in London
London now the global money-laundering centre for the drug trade, says crime expert

Wlecome to London, drug money-laundering centre for the world

'Mexico is its heart and London is its head'
The Buddhist temple minutes from Centre Court that helps a winner keep on winning

The Buddhist temple minutes from Centre Court

It helps a winner keep on winning
Is this the future of flying: battery-powered planes made of plastic, and without flight decks?

Is this the future of flying?

Battery-powered planes made of plastic, and without flight decks
Isis are barbarians – but the Caliphate is a dream at the heart of all Muslim traditions

Isis are barbarians

but the Caliphate is an ancient Muslim ideal
The Brink's-Mat curse strikes again: three tons of stolen gold that brought only grief

Curse of Brink's Mat strikes again

Death of John 'Goldfinger' Palmer the latest killing related to 1983 heist
Greece debt crisis: 'The ministers talk to us about miracles' – why Greeks are cynical ahead of the bailout referendum

'The ministers talk to us about miracles'

Why Greeks are cynical ahead of the bailout referendum
Call of the wild: How science is learning to decode the way animals communicate

Call of the wild

How science is learning to decode the way animals communicate
Greece debt crisis: What happened to democracy when it’s a case of 'Vote Yes or else'?

'The economic collapse has happened. What is at risk now is democracy...'

If it doesn’t work in Europe, how is it supposed to work in India or the Middle East, asks Robert Fisk
The science of swearing: What lies behind the use of four-letter words?

The science of swearing

What lies behind the use of four-letter words?
The Real Stories of Migrant Britain: Clive fled from Zimbabwe - now it won't have him back

The Real Stories of Migrant Britain

Clive fled from Zimbabwe - now it won’t have him back
Africa on the menu: Three foodie friends want to popularise dishes from the continent

Africa on the menu

Three foodie friends want to popularise dishes from the hot new continent
Donna Karan is stepping down after 30 years - so who will fill the DKNY creator's boots?

Who will fill Donna Karan's boots?

The designer is stepping down as Chief Designer of DKNY after 30 years. Alexander Fury looks back at the career of 'America's Chanel'