Clemson University is conducting tobacco research trials designed to test the quality of new varieties, manage insect pests, control bacterial wilt and gauge the effectiveness of solar curing.

Clemson University is conducting tobacco research trials designed to test the quality of new varieties, manage insect pests, control bacterial wilt and gauge the effectiveness of solar curing.
Image Credit: Jim Melvin / Clemson University

FLORENCE — Clemson University and its collaborators are working hard to help tobacco farmers stay ahead of the curve by conducting research trials designed to test the quality of new varieties, manage insect pests, control bacterial wilt and gauge the effectiveness of solar curing.

Though no longer South Carolina’s top cash crop, tobacco remains a profitable commodity in South Carolina, accounting for more than $50 million per year in revenues.

During a recent 2015 South Carolina Tobacco Tour at the Pee Dee Research and Education Center in Florence, scientists shared a wealth of information with farmers, seed producers, tobacco industry representatives and Clemson Extension personnel.

“These trials are helping tobacco farmers be more productive and profitable,” said Trish DeHond, a Clemson Extension area agronomy agent who covers three counties. “We’re looking for the most efficient ways to grow and harvest a high-value crop.”

J. Michael Moore, a tobacco Extension specialist at the University of Georgia who is working in conjunction with Clemson, participated in the three-hour tour.

“One of the things we’re doing is evaluating candidates for new varieties,” Moore said. “We’re happy to have participation from the seed companies here. Tobacco companies also chime in as far as whether this tobacco meets their requirements for a leaf that they would purchase on the market. We look for uniformity of the plants in multiple replications. We look at harvest, yield, grades and chemistry. Eventually, the variety gets a thumbs-up or thumbs-down, but the breeder will always have an opportunity to take it back, clean it up, make sure it’s presentable and try it again.”

Francis Reay-Jones, an entomologist based at Pee Dee REC, discussed the effectiveness of a variety of commercial insecticides in controlling tobacco hornworm, tobacco budworm and other damaging pests.

“We like to include these products every year in our trials,” Reay-Jones said. “And we had larger plots this year that gave us a more realistic simulation of commercial conditions. We recommend that you rotate classes of insecticide when possible to reduce the chances of the development of insect resistance.”

Bruce Fortnum, a plant pathologist and retired professor at Pee Dee REC, described the history of Clemson’s efforts to understand and manage bacterial wilt, a highly destructive disease on tobacco caused by bacteria that live in the soil. Several years ago, Clemson scientists discovered that bacteria wilt is easily spread on machinery during mechanical topping and harvesting in tobacco production. Since then, research at the Pee Dee REC has been focused on stopping the mechanical transmission of the disease.

“I’m really excited about our recent advancements in our ability to control the No. 1 disease plaguing South Carolina’s tobacco,” Fortnum said. “Back in the mid-’80s, we were having epidemics of bacterial wilt in our state, and we really couldn’t figure out what was transpiring. So we approached it from a variety of different avenues, and each one of those areas of research has yielded valuable information on how this disease actually operates.”

Paul Peterson, the current tobacco pathologist at Pee Dee REC, has expanded these efforts and made the station a regional site for comprehensive research on this devastating disease.

“Clemson’s Pee Dee REC plays a unique and vital role in efforts to screen and identify varieties of tobacco with resistance to bacterial wilt,” Peterson said. “We are very fortunate to have the only bacterial wilt testing site with the necessary disease pressure and uniformity to evaluate substantial germ plasm for wilt resistance each year.”

Bruce Fortnum, a plant pathologist and retired professor at Pee Dee REC, described the history of Clemson's efforts to understand and manage bacterial wilt.

Bruce Fortnum, a plant pathologist and retired professor at Pee Dee REC, described the history of Clemson’s efforts to understand and manage bacterial wilt.
Image Credit: Jim Melvin / Clemson University

Peterson added that cooperative trials with pathologists, breeders and chemical companies that market products to producers have provided a breadth of work that covers the many aspects of bacterial wilt control.

“What we need now is an integrated approach that incorporates effective components of our existing bacterial wilt management system with new methods of equipment sanitation and new disinfectants that greatly minimize the spread of this disease.” Peterson said. “I believe that we can substantially eliminate wilt as a major player in our tobacco crop in the near future.”

Russell Henderson, a graduate research assistant in the tobacco program, talked about using solar energy to reduce propane consumption during the curing process. Henderson reported that “preliminary data look encouraging for effectively reducing propane usage.”