Preventive versus curative releases of mirids to control Myzus persicae in sweet pepper
Abstract: In this study we compared four species of mirid predatory bugs: Macrolophus pygmaeus, Dicyphus tamaninii, Dicyphus errans and Dereaocoris pallens on their potential as biocontrol agents of aphids in sweet pepper. Their population development on Myzus persicae was assessed in cages on flowering sweet pepper plants as a curative treatment and when released preventively. Preventive releases on pepper plants were tested without and with additional food (Ephestia kuehniella eggs and Artemia franciscana cysts). The best control of aphids was achieved with M. pygmaeus and D. tamaninii when released preventively in the treatments with supplemental food. None of the mirid species was able to control aphids when released curatively. Additional experiments on Petri dish level showed that M. pygmaeus, D. errans and D. pallens were all able to develop on a diet of aphids and to produce eggs. However lowest mortality during development and highest oviposition rate on a diet of aphids were obtained with M. pygmaeus, which confirmed the result of the greenhouse trial.