Simple mass-rearing technique of a predatory mite Gaeolaelaps aculeifer (Canestrini) (Acari: Laelapidae)

We developed a simple mass-rearing technique for a soil-dwelling predatory mite Gaeolaelaps aculeifer. The rearing container consists of two (inner and outer) plastic boxes. The inner box contains rice husks, and is placed inside the outer box which contains a small amount of water. This system is useful to keep high humidity within the inner box and to prevent mites escaping from the box. The prey mite Tyrophagus putrescentiae was also reared in a similar way using rice bran and provided to G. aculeifer once a week. Rearing condition within the inner box were maintained at 25 ± 1°C, 95 ± 5% relative humidity. In this double box system, G. aculeifer was rapidly grown and overpopulated within two weeks while another predatory mite Stratiolaelaps scimitus require four weeks rearing period. This technique help farmers improve biological control efficacy of soil pests in greenhouse as well as open field cultivation.