Thunderbug: A big challenge for greenhouse growers

a. Neoseiulus cucumeris and Amblyseius swirskii control western flower thrips by feeding on the first instar larvae. A. swirskii can also feed to a lesser extent on second instar thrips. However, they cannot completely eliminate a thrips population.

b. Orius is effective in controlling thrips because it feeds on all stages of thrips.

a. It is often found in the flowers, because pollen is its alternative food source. Since pollen is not often present in ornamental crops, Orius is not as effective in flower crops as it is in vegetables.

b. For greenhouse vegetable crops, Orius is most successfully used on peppers and cucumber.

c. Recent research has shown ornamental peppers can be used as a banker plant for Orius in other crops, allowing a population to establish, develop and disperse within the greenhouse.

c. Stratiolaelaps scimitus and Gaeolaelaps gillespiei are soil-dwelling predatory mites that feed on a variety of soil organisms, including thrips pupae. Research has estimated they can kill up to 30% of thrips pupae.

d. Metarhizium anisopliae or Beauveria bassiana are fungal pathogens of thrips. It can be either sprayed onto the crop or distributed via bumblebees that are supplied with hives specially equipped with dispensing trays. These trays contain B. bassiana spores, and the bees must walk through the trays to leave the hives. In the process, some of the spores stick to their bodies. The spores become distributed in the crop when the bees pollinate the crop's flowers. When thrips come into contact with spores on the crop surface, they become infected and die.

e. Rove beetles, predatory thrips, and green lacewings also help to control thrips.