By Clint Thompson
Beneficial insects could be a citrus producer’s best friend. In a time when farmers are applying insecticides to control Asian citrus psyllids, the vector of citrus greening disease, it’s important to preserve the psyllid’s natural enemies, like lady beetles and lacewings.
Jawwad Qureshi, University of Florida Assistant Professor in Entomology, implores growers to scout their groves periodically to see what insects are present.
“If they know what’s there, then they can strategize their spraying. If they go out there and see a lot of lady beetles or a lot of lacewings, then they can think, maybe I should wait a little or if I have to spray, maybe I should look into the Citrus Production Guide and see which pesticides are relatively less toxic so I can use one of those rather than using something that’s really harsh,” Qureshi said.
Qureshi is not advocating that growers not spray. But they need to evaluate the situation and see what insects are present. They need to conserve and preserve those resources.
“Let’s say you have a good population of lady beetles and you go and knock them down, that means you’ve killed many of those adults that were going to produce the eggs and babies that were going to be useful, not only for you, but for the neighbors and other crops as well,” he added.
Beneficial insects were a lot more visible prior to the discovery of citrus greening disease than they are today. Qureshi said research studies were done at that time and found that beneficial insects knocked down 80% to 90% of the Asian citrus psyllid population.
“Several years ago, before this greening disease was found in Florida, we relied heavily on biologicals in the citrus system. There were a lot of lady beetles, lacewings and other beneficial predators that were feeding on the psyllid,” Qureshi said. “But everybody had to get started on using the insecticides after greening was found. It’s a concern and psyllids were responsible for spreading this disease. Once you start doing that, then definitely we have noticed over the years (the sprays) have significantly impacted the populations of those beneficial insects.
“Now when we go out, sometimes it is hard to find some of those species of lady beetles that we were seeing at that time. That tells you that over the years it has significantly impacted those beneficial organisms.”