Nanogirl Dr Michelle Dickinson: Why your next rose may smell sweeter

Cracking the DNA code of the rose could help roses smell sweeter and bloom for longer. Photo / 123RF

Nothing symbolises love and beauty better than a red rose. Appearing throughout modern Western history in poetry, literature, artwork and films, the rose was one of the sacred plants of Aphrodite the goddess of love.

In the future roses might not only be more beautiful, flower for longer and come in brighter colours but they may also smell that much sweeter thanks to new research released this week.

Wild roses have been cultivated since as early as 3000BC in China where they were originally used as animal-proof fences.

In the 14th century, missionaries introduced Chinese roses to Europe and the extensive hybridisation across the different roses began.

Roses were initially used in the production of rosewater, scented oils and other fragrances. However, thanks to some Roman emperors desires to fill their swimming baths and fountains with rosewater while they sat on carpets of rose petals, the shift to a commercialisation of the flower meant that some peasants were reduced to growing roses instead of food to satisfy their rulers.

This long process of rose domestication has preferentially selected rose plants for flower characteristics including petal colours, fragrance and double flowering, and these traits form the genetic basis of the rose as we know it today.

Although originally stemming from only eight to 20 original species of rose, today there are more than 35,000 varieties of cultivated roses available around the world.

Previously, the only way to develop a new type of rose would be to painstakingly grow thousands of hybrid offspring and look for the combination of flower traits desired.

This process would be repeated again and again until the desired traits were reliably created in each plant. Requiring a lot of greenhouse space, water and soil, it can take up to a decade to craft the perfect rose.

After eight years of research, scientists have now created the first complete genetic blueprint of the rose, which should significantly shorten the time needed to make a new rose while also reducing costs and energy consumption.

The study, which was published in the journal Nature Genetics, used a pink China rose called Old Bush to uncover all 36,477 of the protein-coding genes within the plant.

The researchers were able to find 22 previously uncharacterised biochemical steps that the rose plants can use to make the terpene compounds which give the roses their perfume and determine the regulation of scent and colour in the rose. They also sequenced genomes from ancestral rose species and newer hybrids to help understand the composition, structure and history of the modern rose.

What they found was that some of the genes that control colour and scent work in opposition to each other, meaning that as more beautiful roses have been preferentially selected due to their appearance, their beautiful rose smell has been lost over time.

Interestingly they also found that the rose is genetically linked to the strawberry and also has ties to the apple and pear.

This study highlights the huge advances that we are seeing in genetics as this amount of gene sequencing would have up until very recently cost tens of millions of dollars, but is now much cheaper to run and more widely available.

Cracking the DNA code of the rose could help modern roses to smell sweeter, bloom for longer, be more resistant to disease and use water more efficiently, meaning they will not only last longer in a vase but also potentially reduce pesticide and water use.

So the next time you stop and smell the roses, take care as the next rose you smell might be more potent than you think.

Dr Michelle Dickinson, creator of Nanogirl, is a nanotechnologist who is passionate about getting Kiwis hooked on science and engineering. Tweet her your science questions @medickinson