Program hopes to create rubber-producing sunflowers

DENVER -- Imagine a field of bright yellow sunflowers basking in warm summer sun, leaves thick and deep green, and brimming with enough natural rubber to fashion a set of high-performance tires.

In a decade, it may be reality if an experiment by Colorado State University and government researchers proves successful.

The researchers are trying to increase the amount of natural rubber produced in a sunflower from 1 percent to 10 percent by cross-breeding it with the guayule, a rubber-producing plant, or by stimulating the sunflower's rubber gene.

The guayule (gwah-YOO-lee) plant, which grows wild mostly in the deserts of southwestern Texas and northern Mexico, is more difficult to grow commercially than sunflowers. But it is genetically similar to the sunflower, a crop that thrives in the Great Plains.

The Colorado State's project manager, Lee Sommers, said he hopes to have a prototype in about five years, with a plant ready for commercial production in eight years at the earliest.

Researchers believe the economic benefits would be huge because all the natural rubber used in the United States is imported mostly from Brazil and Malaysia. That's about 1.3 million tons a year, costing roughly $2 billion.

Natural rubber has a higher quality than synthetic, primarily because some of its properties, like elasticity and malleability, cannot be reproduced.

Airplane tires, surgical balloons, surgical tubing, gloves and condoms are made with natural rubber; shoe soles, tire tread and golf ball cores are synthetic, made from petroleum.

The initial genetic research is being completed at the USDA's Agricultural Research Service in Albany, Calif. Department of Agriculture researcher Katrina Cornish said she will work with the rubber-producing trait to try to create several prototypes using different mixes of guayule and sunflower genes.

"We want to make sure we get high-quality rubber," she said. "If we find out sunflowers produce bad rubber, we'll add more guayule genes to create better rubber."