Mirid diversity for multiple pest control in tomato

Abstract: The mirid predatory bug Macrolophus pygmaeus has been used for decades for
biological control of various pests in greenhouse tomato crops in Northern Europe, but the
invasion of Nesidiocoris tenuis and associated pesticide applications strongly disrupted this
stable biocontrol system. In previous experiments we showed that pre-establishment of tomato plants by the heterospecific mirid predators Dicyphus bolivari, Dicyphus cerastii, and Dicyphus errans successfully suppressed N. tenuis populations by more than 90 %. To test the added value of using these species in tomato pest management, we evaluated the control of greenhouse whitefly, the tobacco whitefly, their population growth and risks on plant damage. Both whitefly species were most effectively controlled by M. pygmaeus, followed by D. errans. The population growth of M. pygmaeus was in summertime faster than the other predator species, but in early spring, the predators D. errans and D. cerastii developed faster than M. pygmaeus and D. bolivari. The most severe crop damage was observed for D. cerastii, which makes this species a risky species for biological control. Overall, D. cerastii and D. bolivari do not seem to be suitable candidates for pest control in tomato, but D. errans might have additional value for the control of N. tenuis and pest control in early spring.