Predatory ability of Haplothrips brevitubus (Karny) (Thysanoptera: Phlaeothripidae) on three species of greenhouse thrips.

The predation of adult female Haplothrips brevitubus(Karny) (Thysanoptera: Phlaeothripidae) on 3 species of greenhouse thrips was investigated. The number of secondstage larvae of Thrips palmi, Frankliniella occidentalis, and Frankliniella intonsa consumed by a H. brevitubus female increased with the prey density. The maximum predation number per day against second-stage larvae were 8.7 for T. palmi, 9.4 for F. occidentalis, and 8.5 for F. intonsa, when only thrips were provided, and 16.1 for T. palmi, 14.0 for F. occidentalis, and 8.2 for F. intonsa when the pollen of strawberry was provided along with thrips. These results show a predatory ability almost equal to that of other enemies such as Amblyseius eharai and Amblyseius cucumeris. Therefore, H. brevitubus could be an effective biological control agent for these thrips.