The Environmental Protection Agency has issued a section 18 exemption for use of Topguard fungicide to control cotton root rot in Texas.
The section 18 exemption allows for the temporary, off-label use of Topguard (flutriafol) while product manufacturer Cheminova is in the process of securing a full label. Without a section 18 exemption, it is illegal to use Topguard on cotton and other crops that are not listed on the label.
Tom Isakeit, Texas AgriLife Extension plant pathologist in San Angelo, who has screened various fungicides for root rot management for several years, says Topguard is currently labeled for disease on several crops in the United Sates, including corn, soybeans, peanuts and sugar beets). No full label is available for cotton.
This was the third and hopefully last time that we’ve had to request a section 18 for Topguard on cotton from the Environmental Protection Agency,” Isakeit said. “Once the section 3 label is approved for cotton — hopefully, this year — growers will not have any restrictions for its access for use to control cotton root rot.
If you are enjoying reading this article, please check out Southwest Farm Press Daily  and receive the latest news right to your inbox.
“My understanding of the current situation is that Cheminova has completed field trials to ensure that Topguard residues on cottonseed do not exceed allowable levels. The data from these trials are then reviewed by the EPA, which takes some time. I’ve been involved in section 18 requests for other crops, fungicides to control soybean rust and late blight of potato, for example, and it has taken several years and repeated section 18 requests before the new fungicides received a full label.”
Isakeit said Ken Smith, the technical rep for Cheminova, said use in 2103 in Texas was about equal to 2012, based on sales figures.
Weather played a role in efficacy of the product. “Because of weather conditions, many treated acres did not see a benefit,” he said. “But the benefits are clearly in the millions of dollars. For example, a couple of growers in West Texas had a net benefit of more than $200,000; $336 per acre more in irrigated fields and $182 per acre more in dryland fields.”
Isakeit said most of the feedback on Topguard use has been pretty good. “But it would be nice to gather more economic impact data.”
The section 18 exemption will limit use in 2014 to 288,000 acres in Texas.
The EPA exemption states that Topguard “may be applied by ground equipment at planting either banded into or incorporated into the furrow.”
Maximum rate is 2 pints per acre of formulated product per acre (.26 pounds per acre). No more than one application per year is permitted.