By Clint Thompson
Georgia blueberry producers have viable insecticide options to protect their crop against chilli thrips. They just has to be applied more than once, says Ash Sial, University of Georgia (UGA) entomologist.
“We do have some (options) but they need to be repeated because of the way these chilli thrips, their life cycles work. It’s really hard to knock them down to zero no matter what you do. Repeated applications are needed,” Sial said. “In some cases in Florida, what I heard is they have to make anywhere from nine to 15 applications just to control chilli thrips.
“There’s a lot of costs to it. That’s why we added Agri-mek as a low cost option when you mix that with Rimon. It increases the residual control for a couple of days. It can lower the total number of applications from nine to six or five.”
Chilli Thrips Background
Chilli thrips are an invasive species from Asia that appear later in the season. They are distinguished from flower thrips by their smaller size, incomplete dark stripes on the abdomen and dark wings. They are also different in how they impact blueberries.
Blueberry producers have multiple insecticide options at their disposal, though Sial emphasized that Apta and Assail are most effective. Other options include Agri-Mek, Exirel and Rimon. Mixing Rimon at a lower rate, 10 ounces per acre, may extend the residual activity.
Most of the chilli thrips’ damage is observed at post-harvest. When growers apply insecticides, they are actually protecting the following year’s crop.
“As soon as we stop harvests, most of the growers, the first thing they do is hedge the plants. When you hedge the bushes, during that time there’s a new flush of growth. That very fresh green tissue that comes out of the bushes, that is really tasty and juicy; that’s what these chilli thrips target,” Sial said.