Pee Dee cotton field day addresses biotech questions

By Susan Bedingfield

Technology has affected the way everyone does business – including South Carolina farmers. As technology advances, the agricultural community is faced with tough choices, and as with all businesses, the bottom line is always a concern.

To help farmers cope with these challenges, Clemson Extension held a field day for cotton growers in the Pee Dee area. The field day at the Steven Welsh Farm in Lee County compared yield and quality of biotech cotton with conventional varieties. Cotton varieties containing genes for weed control systems, like Roundup Ready®, are less labor and cost intensive. There are also varieties that control certain insects, which are available with or without the Roundup Ready gene.

Cotton growers are concerned that some of the Roundup Ready varieties have lower yields than conventional varieties. To address these concerns, Lee County Extension agent Randy Cubbage has planted research plots that compare the conventional parent variety with two biotech varieties. “We have established plots side-by-side so growers can see for themselves how the varieties fare in the field,” Cubbage said. “This will help with decision-making at planting time in the spring.”

The Savannah Valley field day was held at Clemson’s Edisto Research and Education Center in Blackville. There, growers saw demonstrations of cotton variety trials, variable-rate irrigation systems, and control strategies for insect pests. They also learned about the role that fungicides may play in controlling “hardlock.”

Hardlock is when lint in the cotton boll fails to fluff enough to be picked up by the spindles of a picker. The affected bolls fall apart and drop to the ground when the spindles hit them. Yields can be cut by 15-20 percent in a wet year like this one, said John Mueller, a Clemson plant pathologist at the Edisto center.
He is part of an interstate team of scientists who are looking for solutions to this problem. One theory is that a fungus, Fusarium verticillioides, causes the condition. Damage from stinkbugs and other insects is another theory. If fungus is the cause, the solution could be as simple as spraying with a fungicide to protect flowers from damage.

To test this theory, Mueller is comparing two cotton varieties with different growth habits to see how they develop and to see if applying fungicides really does have an effect.       
“We want to see if there is a yield response, and to see if it is consistent enough to apply for labels for these fungicides,” says Mueller. Currently no fungicides are labeled for use on cotton but that may change if these test results are positive.