More than 145 attendees gathered on Sept. 13 at the West Tennessee AgResearch Education Center for the Cotton Tour hosted by the University of Tennessee Institute of Agriculture (UTIA). While most attendees were from Tennessee, much of the southeastern cotton industry was represented by participants from Arkansas, Missouri, Mississippi, North Carolina, Georgia, and Alabama. 

UTIA specialists presented a full spectrum of research updates and recommendations at multiple stops during the tour.  

One interesting update came from soil nutrient and management specialist, Nutifafa Adotey. He announced an upcoming publication to provide a new calculation for potassium that is specific to soils in west Tennessee. This equation results from a multi-year investigation on the reliability of the Mehlich-3 and Mehlich-1 extraction methods. 

Another hot topic was ThryvOn cotton technology. Extension cotton specialist, Tyson Raper noted that out of the six UTIA official variety trials, 20% of the cotton entries were ThryvOn varieties. Raper said, “ThryvOn represents a tremendous investment in cotton technology from Bayer,” and he looks forward to testing later maturing varieties of the germplasm in years to come.  

Extension specialists continue to collect data supportive of management adjustments for ThryvOn cotton. Research will determine new recommendations for managing things like plant growth regulators and plant bug thresholds.  

Related:Cotton defoliation timing always challenging, especially this year

Sebe Brown, Extension research entomologist noted that while ThryvOn cotton provides excellent thrips protection, growers must tailor their expectations to the technology.  

“ThryvOn cotton contains a protective protein in the plant, and the thrips must bite the cotton to ingest the protein. There may be some cosmetic damage from thrips in ThryvOn cotton, but it will look exceptionally better than non-ThryvOn cotton,” Brown said. 

He added that it will take more data to determine whether plant bug thresholds should be altered. Square retention is part of the test, and Brown recommends to scout early. 

“Some of this year’s ThryvOn varieties are fruiting on the fourth node as opposed to the tenth node, so scout for plant bugs early in the season and treat at the current thresholds,” he said. Brown also noted that ThryvOn has no activity against stinkbugs so producers must spray for those. 

Regarding weed control, Extension weed specialist Larry Steckel spoke of a three-year project with the John Deere See and Spray agronomy test machine. The technology detects weeds with cameras and tells the solenoids on when to spray. 

Related:USDA refining of forecasted U.S. cotton production

Steckel said, “The sky is the limit with this technology, and it will make us a lot more efficient.” 

Additionally, Steckel reported on herbicide resistant ryegrass, goosegrass, barnyardgrass, and pigweed.  To control ryegrass, Steckel suggested fall residuals after harvest along with earlier spring burndown applications, and he recommended overlaying residuals to control pigweed breakthroughs. 

Delivering the cotton disease update was Heather Kelly, Extension research plant pathologist. She said the first confirmed case of areolate mildew in Tennessee was reported in 2022 there at the research station in Madison County.  

The disease presents as white fluffy growth on the underside of leaves in the lower canopy and can quickly defoliate affected cotton plants. Kelly cautioned that areolate mildew overwinters on debris and spores can blow in from the south.  

On the sustainability front, Lori Duncan, crop sustainability specialist discussed an on-farm research project in Ashford, Tenn., investigating the impact of soil compaction on water infiltration and drainage. Data from 2022 indicated a significant difference amongst seven traffic treatments that included tillage, no-tillage, sprayer wheel tracks, and a combination of the three. Ongoing research will determine the benefit of prescribed traffic routes through the field. 

Crop physiologist, Avat Shekoofa also reported on a sustainability study. The investigation compares the differences in water movement in conventional cotton plants versus cover cropped cotton plants. Shekoofa described new sensor technology that measures water pressure inside the plant and said to expect data at the end of the season. 

Finally, the 2023 Cotton Tour marked the first year to include other rotational crops like soybean, corn, and peanut – all planted in rotation with cotton. Research specialist, Drew Denton discussed the demonstrations. He described the soybean study that looked at desiccation rates and product recommendations based on six planting dates of the same hybrid variety at two maturities, 4.8 and 6.5.  

The corn study compared nitrogen fertigation to aerial applications at different timings, and the peanut study found that runner peanut varieties may fit as an excellent rotational crop for cotton in some areas of western Tennessee.