Louisiana: Field Day Features Sweet Potato Trends

CHASE, Louisiana (August 15, 2008) – Trends in the sweet potato industry are showing a shift toward more processed products, LSU AgCenter experts said at a field day at the AgCenter’s Sweet Potato Research Station Aug. 14.

About 70 sweet potato producers and industry representatives were on hand to learn how to produce a predictable, profitable crop.

Although 60 percent of Louisiana sweet potatoes have been sold in the fresh market, the market is growing closer to 50 percent fresh and 50 percent processed, said Dr. Tara Smith, the LSU AgCenter sweet potato specialist and station coordinator.

“We are starting to cater some of our research and extension efforts in that arena,” Smith said. Processed items include juices, pre-packaged cakes, French fries, cookies and baby food.

The heart of keeping the sweet potato industry going strong in the state is the foundation seed program, which is a major function of the station, Smith said. Each year the station produces 6,000-10,000 bushels of foundation seed potatoes, which are sold to Louisiana producers.

“We know how to produce virus-tested sweet potato tissue cultures,” said Dr. Chris Clark, LSU AgCenter plant pathologist. “We know that they yield significantly better than plants from older seed infected with viruses.”

Dr. Jeff Davis, LSU AgCenter entomologist, told producers they can prevent virus transmission by using certified seed, insecticides to control the vectors that transmit the virus, barrier crops and crop oils.

“Viruses can reduce yields 30 to 50 percent and affect quality,” Davis said.

He said the LSU AgCenter is trapping aphids at various research stations across the state. Aphids are important virus vectors because they are prolific and develop winged forms that travel easily.

The high point of research is releasing a new variety valuable to the industry, said Dr. Don Labonte, discussing the Evangeline sweet potato variety, which was released by the LSU AgCenter in 2007.

“It is very good as a processing sweet potato.” he said. Evangeline has deep orange flesh, a round shape, and good disease and root-knot nematode resistance.

Crop rotation is a viable management option for both the reniform and root-knot nematodes, said Dr. Charles Overstreet, LSU AgCenter plant pathologist. Reniform is the dominant nematode in sweet potatoes in Louisiana.

“Try to use some kind of crop rotation if you can” to control nematodes, he said.

Overstreet said a rotation crop should be planted for two consecutive years following sweet potatoes to be effective in nematode control. Cotton and soybeans are preferred hosts of the reniform and root-knot nematodes and should be avoided as rotation crops with sweet potato when possible, he said.

Corn, grain sorghum and fallow fields are considered good rotation schemes for managing reniform nematodes, he added. Corn, however, is a host for root-knot nematode.

“Don’t get yourself in a situation where nematodes are causing problems, and you don’t know about it,” Overstreet said.

“We really appreciate the support of the sweet potato industry,” said Dr. David Boethel, LSU AgCenter vice chancellor and director of the Louisiana Agricultural Experiment Station. “Sweet potatoes are something we are going to be in business for for a long time.”

Mark Fields, president of the Louisiana Sweet Potato Association, said the LSU AgCenter Sweet Potato Station’s research team is “the envy of the nation.”