Gourmet-style Thai jasmine rice may be future U.S. crop

September 11, 2001

BELLE GLADE, Fla. — An experimental plot of rice known as Thai jasmine comprises only a tiny fraction of the rice grown annually in Florida, but that humble beginning may one day lead to thousands of acres of the prized crop if a University of Florida researcher is successful.
To accomplish that, Chris Deren has been bombarding rice seeds with gamma rays.

“The challenge is to create mutations that will flower early,” said Deren, a professor of plant breeding and genetics with UF’s Institute of Food and Agricultural Sciences. “That allows the plants to grow and be harvested prior to the onset of the colder, fall season in North America.”

Collaborating on the project with Deren, who oversees the experiment, are the University of Arkansas and the USDA’s National Rice Research Center.

Thai jasmine rice is indigenous to Thailand, but is not well suited to North America because temperatures below 50 degrees Fahrenheit halt growth of the plant. Deren said that in Thailand, when the days get shorter in the fall growing season, temperatures are still warm enough for the plants to produce rice.

But that’s not the case in North America, not even in the warmer climate of Florida.

“Normally, Thai jasmine rice would be planted in March or April, and it would begin to flower when days have less than 12 hours of sunlight, which is in the fall. But by then, it’s too cold at night for the plants to produce grain, which is why we have to alter the genes so the plants bloom earlier,” Deren said.

Deren said rice growth is influenced by the length of the day. In October, when days begin to have less than than 12 hours of sunlight, it signals the rice to start flowering and producing grain.

This scientific phenomenon is called photoperiod sensitivity, which many living organisms – including human beings — respond to, Deren said.

To get the rice to grow in Florida, he used gamma rays to genetically alter the plants so they would be non-responsive to day length, which allows the rice to be grown during the usual rice season.

“We want to create a day-length insensitive variety that can be planted whenever we want and it will flower 90 days later,” Deren said.

In addition to altering the photoperiod gene, Deren also manipulated the rice to grow about 12 inches shorter than traditional Thai jasmine plants. Called semi-dwarf rice, it does not fall over as it matures, which is crucial to commercial production.

“In Thailand, the rice is harvested by hand, so it’s OK that it grows tall and bends over,” Deren said. “But here, we harvest by machine, which demands that the rice grows no higher than about 3 feet. The shorter plants also have stronger stems, which helps buffer the plant against hurricane winds.”

To select rice in which the desired traits are most highly represented, Deren tracks about 500 varieties at UF’s Everglades Research and Education Center in Belle Glade. The 1.5-acre experimental plot is miniscule compared with the 20,000 acres of rice harvested annually in Florida.

But if all goes as planned, Florida will have a commercially viable crop in about 10 years, which is how long Deren said it will take to perfect the Thai jasmine rice.

The United States imports about 350,000 tons of Thai jasmine a year, but American companies such as West Palm Beach-based Sem-Chi Rice Products would like to change that.

Klaus Senglemann, general manager of Sem-Chi, said there is an ever-increasing demand for Thai jasmine, and if Deren can create a high-quality product, Sem-Chi would plant about 9,000 acres of it.

“We can get about $26 per 100 pounds for a Thai jasmine variety that is comparable to the products imported from Thailand,” Senglemann said. “That’s about $9 more per 100 pounds than what we get for our standard varieties of rice.”

Senglemann said connoisseurs prefer Thai jasmine because of its distinct “popcorn” aroma, bright white color, superior taste and softness after cooking.

In addition to the scientific challenge of genetically manipulating the rice to thrive in a new environment, the scientists face the task of convincing growers of the benefits of growing rice in Florida.

“The truth is, rice has traditionally been grown as a rotation crop in Florida primarily to make sugar cane crops better,” Deren said. “What we are trying to do is make rice an attractive crop on its own merits.”