Clemson Agronomic and Vegetable Field Day highlights

Tarnished plant bugs and thrips are major insect pests for South Carolina cotton. But Clemson University researchers assure growers help is on the way.

During the 2022 Agronomic and Vegetable Field Day at the Edisto Research and Education Center (REC) in Blackville, South Carolina, Clemson entomologist Jeremy Greene told growers, although not available now, Thryvon Bt technology from Bayer has been found to show increased protection against these pests in cotton.

Clemson Agronomic and Vegetable Field Day highlights

“Pending regulatory approvals, Thryvon should be available soon,” Greene said.

To predict thrip risks, Greene encourages the use of the Thrips Infestation Predictor for Cotton tool, https://products.climate.ncsu.edu/ag/cottontip/. This tool predicts thrip risks using information based on field location and planting date.

As for the effectiveness of other cotton technologies China’s Access to Chip Technology, Greene reported bollworms are developing resistance to older traits used in Bt cotton.

Other cotton insect pests growers should pay attention to include the brown marmorated stink bug, green stink bug, southern green stink bug and other species.

Bhupinder Farmaha, Clemson Cooperative Extension Service nutrient management specialist, is conducting an on-farm study related to cover crops and fertility management. This research is being conducted to determine how to make future nitrogen recommendations related to soil health.

Farmaha is looking for farmers to participate in this study. Farmers who want to get involved are asked to contact Farmaha at (217) 778-5170 or their local Clemson Extension agent.

Irrigation, double cropping, nematodes, nitrogen management and herbicides
Other topics discussed at the field day included a discussion by Jose Payero, Clemson Extension irrigation specialist, about the potential use of subsurface drip irrigation (SDI) to irrigate row crops in fields where installing a center pivot would not be feasible. Payero also discussed and demonstrated the use of a wireless sensor network to automate irrigation based on real-time soil moisture data.

Clemson doctoral student Bennett Harrelson talked about his research related to double-cropping soybean after corn. Harrelson is studying under Michael Plumblee, Clemson Extension corn and soybean specialist, and is looking at several different agronomic factors revolving around the double crop corn and soybean production system including planting and harvest dates, row spacing and the use of at-plant nitrogen. The researchers also are studying to determine if this double-cropping system leads to issues with plant-parasitic nematodes building up under certain scenarios.

Nematodes can present issues for South Carolina farmers. John Mueller, Clemson Extension row crop pathologist, talked about nematode management in cotton and soybeans. Mueller also talked about fungicides for foliar diseases in cotton and soybeans. Seed treatment fungicides normally do a good job of controlling seedling diseases in soybeans. Seedling diseases occur on South Carolina cotton every year. Disease incidence and severity are determined by environmental factors such as soil temperature and moisture, as well as by seed quality and vigor. Seedling disease management relies on using cultural practices and fungicides.

Participants also heard about nitrogen management in grain sorghum by Alex Coleman, in addition to information about seedling cotton response to pre-herbicides and 2,4-D herbicide programs in Enlist Soybeans by Sarah Holladay, Clemson doctoral student, and Michael Marshall, Clemson Extension weed scientist.