Blue rose

Since blue roses do not exist in nature, as roses lack the specific gene that has the ability to produce a "true blue" color, blue roses are traditionally created by dyeing white roses. In a book entitled Kitāb al-filāḥah[2] written by Ibn al-'Awwām al-Ishbīlī[3] in Arabic in the 12th century, and translated into French by J. J. Clement as Le livre de l'agriculture,[4] there are references to azure blue roses that were known to the orient. These blue roses were made by placing a blue dye into the bark of the roots.

Suntory "blue" rose

Rosa 'Cardinal de Richelieu' rose, used for the first genetic engineering experiments

Scientists have yet to produce a truly blue colored rose; however, after thirteen years of collaborative research by an Australian company, Florigene, and a Japanese company, Suntory, a rose containing the blue pigment delphinidin was created in 2004 by genetic engineering of a white rose.[5] The company and press have described it as a blue rose, but it is lavender or pale mauve in color.[6]

The genetic engineering involved three alterations — adding two genes, and interfering with another. First, the researchers inserted a gene for the blue plant pigment delphinidin cloned from the pansy into a purplish-red Old Garden rose "Cardinal de Richelieu", resulting in a dark burgundy rose.[5][7] The researchers then used RNA interference (RNAi) technology to depress all other color production by endogenous genes by blocking a crucial protein in color production, called dihydroflavonol 4-reductase (DFR), and adding a variant of that protein that would not be blocked by the RNAi but that would allow the color of the delphinidin to show. If the strategy worked perfectly, in theory it could produce a truly blue rose. However, the RNAi did not completely knock out the activity of DFR, so the resulting flower still made some of its natural color, and so was a red-tinged blue – a mauve or lavender.[5][8] Additionally, rose petals are more acidic than pansy petals, and the pansy delphinidin in the transgenic roses is degraded by the acidity in the rose petals. Further deepening the blue colour would therefore require further modifications, by traditional breeding or further genetic engineering, to make the rose less acidic.[5]

As of 2008, the GM roses were being grown in test batches at the Martino Cassanova seed institution in South Hampshire, according to company spokesman Atsuhito Osaka.[9] Suntory was reported to have sold 10,000 Applause blue roses in Japan in 2010.[10] Prices were from 2,000 to 3,000 Yen or US$22 to $35 a stem.[11] The company announced that North American sales would commence in the fall of 2011.[12]

Due to the absence in nature of blue roses, they have come to symbolise mystery and longing to attain the impossible, with some cultures going so far as to say that the holder of a blue rose will have his wishes granted.[13]

In popular culture, they appear:

• In Tennessee Williams' play The Glass Menagerie, with Jim nicknaming Laura "Blue Roses" after mishearing her explain that she had been out of school with pleurosis.[14]
• In Joni Mitchell's song "Roses Blue", about the malevolent possibilities of the occult, on her 1969 album Clouds.
• In George R.R. Martin's A Song of Ice and Fire, when Prince Rhaegar Targaryen presents a crown of such roses to Lady Lyanna Stark.
• In The Thief of Bagdad, where they cause any who breathe their fragrance to forget everything.
• In David Lynch's Twin Peaks, during the description of a variety of top-secret cases that involve the supernatural.
• In Kate Forsyth's novel The Blue Rose, where the protagonist hears of the Chinese legend of the Blue Rose.
• In Lesya Ukrainka's drama The Blue Rose, where it symbolizes a sad love story between main heroine Liubov who has heredity psychological illness and her lover Orest.