The irony of giving roses as a symbol of everlasting love is their imminent death.
N.C. State horticulturists are looking to solve that problem by unlocking the mysteries behind the rose’s short lifespan – and to extend it.
John Williamson, associate professor of horticulture, works with stress physiology. He studies why plants are resistant to various kinds of pressures. He is one of the professors in charge of the research to strengthen the rose.
“The basic problem we are addressing is what the consumer sees when they buy the rose…very often, it’s gone in a couple days,” Williamson said. “With a really good florist that is doing everything they should, you can probably get a week out of [a rose].”
Williamson hopes to vastly extend the consumer vase life of the long stem rose. In order to do this, he and the other researchers have enlisted the help of an enzyme called mannitol dehydrogenase that is found in many plants, including celery.
The enzyme, mannitol, was used as a sweetener and is also an antioxidant. In plants, it is metabolized to help fight off pathogens like the common petal blight. Petal blight is the brown discoloration often found on the edges of the petals of flowers.
Jennifer Garr, a senior in biology, said she received flowers for Valentine’s Day. Even though she used the plant food that came with them, they still turned brown after just a couple days.
“I think [flowers] would be a better investment if they lasted longer,” Garr said.
The use of celery for extraction of mannitol dehydrogenase happened completely by chance.
According to Williamson, celery is salt and drought tolerant which makes it ideal for use in gene extraction. Researchers have tested the usefulness of the gene in other flowers, and so far, the outlook is good.
“At this point, we have not done any resistance testing on the roses,” Williamson said. “We have done testing on other ornamental [plants.] It looks good so far.”
So far, researchers have tested ornamental tobacco, known as nicotiana. Resistance test results from this plant are positive, which means that other plants could yield the same results.
Roses are top priority because they dominate the flower industry.
“Roses are probably one of the highest dollar legal crops you can grow,” Williamson said.
However, due to the climate, the majority of roses we buy in the United States come from South America, mainly Columbia. If the research is successful, it will likely be licensed to companies for use in South America.
“We still grow a lot of cut flowers in this country, just not roses,” Williamson said. “We grow lots of lilies, [which are] probably almost as expensive as roses per stem.”
When creating genetically modified plants, there are concerns with the modifications escaping into other surrounding plants, creating “super-weeds.” However, this is not a problem because researchers are creating a resistance to a naturally occurring pressure.
“We’re taking a gene from a food you eat and putting it into a plant that you typically don’t eat,” Williamson said. “So in terms of safety of the resulting product, it’s probably as safe as you are going to get with any kind of cross.”
Williamson said the concern is rational, but the government places a lot of regulations on genetic modifications.
Austin McPhail, a junior in psychology, said he sees nothing wrong with genetically modified plants – as long as the researchers stick to just flowers. If there was a way to make them last longer, McPhail said he would be willing to spend more money on flowers for his girlfriend.
Despite the hype, Williamson said the research on roses has just begun. To introduce the gene into the plant, it is first put into a bacterium. That bacterium is used to get the gene into a cell, usually a single plant cell. The plant cell then has to be regenerated back into an entire plant.
This process poses the most time consuming part. Researchers have to find optimal conditions to get that cell to regenerate back into a plant that meets all the standards of flower growing, including smell, aesthetic and vase life.
“The roses are the least far along,” Williamson said. “We’ve got the genes in. We are in the process of verifying that the genes are being expressed properly.
Plants in the greenhouse that have the gene, including tomatoes and geraniums, are noticeably greener and healthier looking. Williamson said he is pleased with these results.
“We are very hopeful for the roses,” Williamson said. “Flowers help make people happy.”
alt: how to keep flowers fresh
Until the research is complete, rose consumers can do a few things to keep their roses in optimal condition. Try to buy roses from a florist that keeps the roses in near-freezing temperatures. This slows the metabolism of the rose and keeps it looking fresh for a longer period of time.
Always use the powder that comes with most flowers. If the flowers don’t come with food, then use a clear, non-diet soda. It has everything a flower needs: a balanced pH, preservatives, and most importantly, fructose (sugar).
