A faulty pump in the cells of petunia petals is the reason why they are blue, a rare colour in the flower world.
Scientists say the new finding may help to explain and manipulate the colour of other ornamental flowers, not to mention the taste of fruits and wine.
The cellular pump, which was previously unknown in plants, fails to work properly in some petunias, preventing the petals from acidifying special compartments within their cells.
As a result, those petals turn blue instead of red or violet, much like the litmus paper some will recall from chemistry lessons.
“Blue flower colors have been enigmatic for a long time and the blue rose appears in many myths,
legends, and even operas,” said Francesca Quattrocchio of the VU-University in Amsterdam.
The findings are published in the journal Cell Reports.
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