Influence of host age and low-temperature storage on parasitization by the egg parasitoid Trissolcus japonicus (Hymenoptera: Scelionidae)

We investigated the usefulness of cold-stored eggs of the fruit-piercing stink bug, Glaucias subpunctatus (Walker) (Hemiptera: Pentatomidae) for a field survey of the egg parasitoid Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae). Laboratory surveys revealed the effects of host age and storage under low temperatures on parasitism. The rate of parasitizing 0-3 day-old host eggs was close to 100%, but it significantly decreased for 4 and 5 day-old eggs. The storage temperature and the storage period significantly affected the parasitism rate. Adequate parasitism rates of eggs stored at + 4 or - 80 ? were also confirmed in a field survey. From these results, we clarified the optimal age and storage temperature of host eggs for a field survey of this egg parasitoid.