Researchers on quest for cold-resistant cane
By JOHN HARPER
SCHRIEVER, La. (AP) — Genetic modification has become somewhat of a buzz term in the politically charged debate over modern agricultural practices and organic food supply.
In practice, however, modifying sugar cane to grow better is still done much the same way as it was 100 years ago when the U.S. Department of Agriculture opened its research center in Houma.
Very little of the work that goes into genetically engineering crops takes place in a laboratory.
That’s why USDA research geneticist Anna Hale shivered through a 30-degree wind chill in Schriever one recent morning, grabbing up her last set of samples for the season.
It is the frigid temperatures that make timely her most recent stock of sugar cane, gathered in batches of 10 to be weighed and tested for purity and sugar content.
“The focus of our breeding is trying to find cold-resistant cane,” Hale said. “We have the most cold-resistant varieties in the world right here.”
Farm manager Harold Callahan remembers one year when temperatures dipped into the low 20s.
“Everything dried up, split apart, except one cane,” he said. “There was one cane that was still just as green as it was during the summer. They are still using that cane today.”
Finding a cane that is both durable in cold weather and produces large quantities of sugar takes decades of planning and years of tedious labor. Because sugar cane varieties deteriorate and become disease prone after just a few years in the field, the sugar cane research center continually churns out new varieties of crop.
That means, just to keep up with the need for new varieties, the research center has around 240,000 different cane varieties on the 40-acre property at any given time.
“You can make the same cross over and over and over again and get a different result each time,” Callahan said. He likens the breeding of two different cane types to the punnett squares shown in high school science classes that display the probability of inheritance of human genes.
All told, crosses sufficient to produce one cane variety can take around 13 years for a commercially available sugar cane variety, or up to 26 years for research varieties like the one Hale is working on producing.
“You’re looking to breed a merit scholar with an all-American athlete,” Hale said. “You have to be choosy about what you bring in to cross.”
The crossing begins with a small patch of scrawny cane that sits in front of the centers new multi-million dollar genetics greenhouse. The wild canes are imported from around the world, many from Asian countries where cane grows near the base of mountains and can develop cold hardiness.
Those canes, however, are useless to sugar growers, Callahan said.
“There’s no sugar in any of those,” he said. “To get a variety that can be used you have to breed it with commercial cane.”
Commercial cane used in Louisiana has thick, juicy stems that contain high quantities of sucrose, the compound that makes up sugar.
All of the samples that Hale collects are labeled with a barcode, tested in a laboratory for their sucrose content, purity and potential sugar yield, and then entered in a database that is combed over by dozens of research scientists at the Houma facility and at research facilities at LSU and in Florida.
Because sugar cane only flowers in a tropical environment, where day and night hours are approximately equal, the cane in Houma has to be forced to flower. This is done by a controlled garage-like facility that automatically rolls the cane outside at only certain times of day and uses ultraviolet lighting to supplement during darker months.
Then the flowering canes are tied tightly together in a greenhouse for two weeks, the seeded flowers of the female plant then kept and germinated in one of 100,000 cells in the Houma greenhouse throughout the winter before being replanted in the field, one 15-foot patch at a time, to be tested the next year.
“The problem is you won’t know what the outcome is for 13 years,” Hale said. “We are lucky to get one variety out of 100,000 cuts that we put in the greenhouse.”
That one variety, the 1-in-100,000 combined miracle of nature and science, becomes the newest genetically improved sugar cane crop. Just a hair stronger and a touch sweeter than the one that came before, she said.
Information from: The Courier, http://www.houmatoday.com