A rose could smell as sweet again, if research cash became available
A world-famous plant geneticist says commercial roses that have no more aroma than a head of lettuce could regain their powerful, natural rose scent.
Harry Klee even says he knows what gene they’re missing. Just one crucial gene, he believes. But he and his lab at the University of Florida have given up trying to reintroduce it because roses are so difficult to work with.
Also, no one wants to pay for rose research. Klee now works with tomatoes instead.
“We did (rose research) for a period of time, but they are too difficult to transform, from the point of making a transgenic plant,” he said Friday.
“They’re so technically challenging for us — they take so long — that we said no, we just can’t put these kinds of resources into it.”
The job was straightforward but slow.
“If we want to stick a gene into a tomato plant, we can do that in four to six months and have the plants in the greenhouse and get seeds back from them,” he said. But roses take more than a year for every such step.
“Nobody was paying us to do this research and we were spending a lot of resources on doing it. (But) it can be done. We know exactly how to do it.
“If a company wanted to pay us to do it, we could probably do it starting today ... The science is very straightforward.
“The hard part is identifying the gene that makes the chemical, and that we have already done.”
But corporate backers don’t want to wait for slow research.
The single most crucial gene happens to exist in tomatoes as well, where it’s part of the complex source of tomato scent and flavour. It is the gene for an enzyme called aromatic amino acid decarboxylase, or AADC.
Commercial roses lost their scent because it was treated as an afterthought, Klee says.
“The breeders have really focused on the appearance, and getting these big, healthy, hardy roses that they can ship long distances. They have lost the aroma, basically through just neglect. Which is almost exactly the same story as has happened with tomatoes” that have lost flavour.
Rose scent “has just been sort of randomly lost from the pool.” There are still old-fashioned roses that smell nice, but these aren’t big and strong enough to ship from the major growers in South America.
He believes that if breeders had selected hybrids both for looks and scent, the original rose scent could have been preserved.
In the meantime, Klee is breeding tomatoes, and is having success crossing genes from heirloom varieties into hardier hybrids for sale to home gardeners. The hybrids are all products of conventional breeding.
His Garden Treasure and Garden Gem cultivars are becoming popular, and he had a widely read research paper in the journal Science a couple of weeks ago.
Roses, though, will have to wait.