Performance of Orius insidiosus after storage, exposure to dispersal material, handling and shipment processes

Bueno, V.H.P.; Carvalho, L.M.; Lenteren, J.C. van


Storage, handling and shipment procedures are important factors influencing the quality of biological control agents. This study aimed to evaluate biological parameters and performance of Orius insidiosus (Say) after different storage periods at low temperatures, after exposure to different dispersal materials in containers, and after handling the predator during the shipment and delivery processes. Storage periods were 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 days at temperatures of 5, 8, 10 and 12 ± 1 °C, RH 70 ± 10% and under continuous scotophase. A mix of 75% adults and 25% 5th instar nymphs of O. insidiosus was kept in plastic containers (200 mL) for a 72 h period, supplied with eggs of Anagasta kuehniella (Zeller) as food, farmer’s friend inflorescence (Bidens pilosa L.) as oviposition substrate and source of moisture, and one of the following dispersal materials: vermiculite + rice hulls (1:1), vermiculite, folded paper towels, sawdust, and coffee husk. Also, similar mixes of nymphs and adults were exposed to a 72 h shipment and delivery process. We found that O. insidiosus can be stored up to 10 days at 8 °C without loss of quality. Interestingly, storage of mated female predators results in a much higher fecundity post-storage than storage of virgin females. Vermiculite + rice hulls was by far the best dispersal material, and shipment of the predators by post during 72 h in Styrofoam boxes with plastic containers with vermiculite + rice hulls and A. kuehniella eggs did not negatively affect their survival and predation capacity. Our results can be used in planning mass-rearing and shipment, and to improve the quality of the predator O. insidiosus by using the right storage temperature, storage period and dispersal material.