Soon, express love via blue roses

For all those lovebirds out there, the fairytales' blue roses may soon become a reality.

Researchers have unearthed a mechanism that gives that extraordinary colour to some flower petals.

"The discovery is a kind of cellular pump that was previously unknown in plants. When that pump fails to work properly, as it does in some petunias, the flower petals can't acidify special compartments within their cells. As a result, those petals turn blue instead of red or violet," said Francesca Quattrocchio and Ronald Koes of VU-University in the Netherlands.

The pump is composed of two distinct proteins, which together build acidity even when other pumps would stop. Blue petunias are blue because of genetic defects that leave that special pumping system out of order, said the study that appeared in the journal Cell Reports.

"Earlier theories proposed that blue flower colours were caused by reduced acidity of the 'cell sap'. Others proposed that blue flower colours had something to do with the formation of metal-anthocyanin complexes (a chemical complex giving colour to petals of certain plants). Our current opinion is that both got it right," said Quattrocchio.

The findings may help to explain and manipulate the colour of other ornamental flowers, not to mention the taste of fruits and wine, say researchers.

"Now we have the tools to isolate plant varieties with different acidification levels in their vacuoles. This could prove very fruitful when it comes to generating new colours in valuable flowers or new tastes in fruits, wines, and juices," added Quattrocchio.