A lot has transpired since I received a text from Justin Odom, ANR Agent in Seminole County, on July 9, 2025 which included pictures of cotton jassid infesting okra. Who would have ever thought we would be where we are today. As a review cotton jassid or the two-spot cotton leafhopper, Amrasca biguttula, was detected in Puerto Rico in 2023 and in Florida in 2024. There were reproducing jassid populations in south Florida and an adult was found in Jackson County Florida which borders Georgia and Alabama. The first field treated for jassids in Georgia was in Appling county in late July. Jassid populations tended to be earlier and higher in east Georgia, south of a line between Colquitt and Emanuel counties. However, jassids eventually spread across all cotton producing areas in Georgia, even northwest Georgia near Rome and northeast Georgia near Madison. To date cotton jassids have been found on cotton in Georgia, Florida, Alabama, South Carolina, North Carolina, and Mississippi.
We are on the tail end of insect management for this crop. However, we must remain vigilant with scouting and treating when necessary for all insect pests. Our current suggested threshold for jassids is 1-2 nymphs per leaf. We are suggesting that we protect cotton from jassid until we are 20-25 percent open and the field is still green. That is approximately 2 weeks prior to the earliest you could defoliate a field. Plant injury from jassids includes hopper burn and yellowing of leaves and leaf puckering. When feeding jassids inject a salivary toxin which causes this plant injury. These leaves will ultimately turn red and may begin to dry up. There is a delay is plant injury symptoms following feeding but we know fields can express severe symptoms in as little as 14 days in the presence of high jassid infestations which is why we suggest managing jassids until 20-25 percent open. We need green leaves to properly fill immature bolls in the top of the plant. Recent preliminary data suggest leaf productivity (photosynthesis) declines significantly as leaves show hopperburn and yellowing symptoms and declines even further as leaves begin to turn red. We believe it is important to defoliate jassid infested fields in a timely manner. If uncontrolled, leaves may turn brown and desiccate and that could create problems with defoliation.
What about post-harvest management? Again, this is a new pest and we are still learning, but destruction of stalks and not allowing regrowth is advisable. Regrowth will allow jassid populations to continue to build for the remainder of the fall until we get a “killing” frost. We have many questions regarding winter survival of jassids, but it just makes sense to do everything we can to minimize buildup of populations after harvest. This same cultural management principle applies to whiteflies. As we have done this season, as we learn more we will provide updates to your local county agent.