Last October’s historic flood landed a hard blow to South Carolina cotton farmers, one they are not over yet.

USDA pegs South Carolina planted cotton acreage at 190,000 acres, down from 235,000 acres last year. “With the kind of season we had last year with the floods, we lost a lot of growers. Prices are not good, so our acreage is down,” said Clemson University Cotton Specialist Mike Jones at the Pee Dee Research and Education Center 2016 Field Day in Florence Sept. 13.

Jones noted that USDA in its August estimate put South Carolina’s average yield at 918 pounds per acre for this year’s cotton  crop. “I’m not sure where they are getting that number from or what cotton they’re looking at, but I think it’s more like 700 pounds for a state average; 918 pounds will put us close to our record yield," he said.

Jones said the Pee Dee region had good rain in some areas, but much of the state has been extremely hot and dry, which takes a toll on yields even though cotton  comes from a tropical area and is somewhat heat tolerant.

“What you’ll see is the plants have lot of bolls on them,  but the way a cotton boll develops,  it has three to five locks and within each lock you usually have between eight and 12 seeds per lock and when you have a lot of heat you get poor pollination. So if you look at a lot of these cotton bolls the locks in them are only going to have five to eight seeds. When we go to put the pickers in here, you’re going to think you’re picking a lot of cotton, but it’s not going to have a lot of weight to it,” Jones said.

At the field day, Jones highlighted the variety testing program conducted across South Carolina. Clemson conducts both small plot and large plot research at the Pee Dee Center and  the Edisto Research and Education Center in Blacksville. The same varieties are planted at both sites  under both irrigated and dryland conditions. Both early and late-maturing varieties are planted.

“With funding from the South Carolina Cotton Board, we are able to take these variety trials out across the South Carolina landscape. We have one trial in Dillon County with Daniel Baxley, one in Lee County with Pete Blair and one in St. Matthews County with Kent Wannamaker,” Jones said.

Kari Hugie, research geneticist with USDA’s Agricultural Research Service in Florence, emphasized the importance of increasing the genetic diversity of cotton to both improve agronomic traits and improve fiber quality. She called genetic diversity “the foundation of crop improvement.”

“Modern cultivars represent only a small fraction of the total diversity present in cotton,  and low genetic diversity can not only limit progress but it can also lead to crop vulnerability,” she said.

She said USDA’s germplasm cotton collection is a large and a relatively underutilized resource of genetic diversity for t cotton, containing both exotic varieties and landraces. In her research, Hugie is examining selected landraces with the hope of identifying variations for improved fiber quality and other important economic traits.

At the Pee Dee Center, researchers are using tractor-mounted sensors to measure plant growth and development throughout the season under different irrigation treatments with the goal  of identifying drought tolerance in some of the unimproved landraces.  Hugie said DNA sequencing technology is also used to measure diversity at the DNA level with the ultimate aim of identifying genes  of interest.

“Even if we find useful variations in these landraces, it takes a long time to incorporate those into more elite material,” Hugie explained. “We started evaluating breeding populations and have established some crosses between selective landraces and more elite lines in the breeding program.”

Clemson Cotton Specialist Mike Jones said South Carolina lost a lot of cotton farmers this year due to low prices and last October’s devastating floods.

Kari Hugie, research geneticist with USDA’s Agricultural Research Service in Florence, says genetic diversity is the foundation for crop improvement.