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Successful biological control of the whitefly Bemisia tabaci involves the mass rearing of biocontrol agents in large numbers for field release. Cold storage of the biocontrol agents is often necessary to provide a sufficient number of biocontrol agents during an eventual pest outbreak. In this study, the fitness of two whitefly parasitoids Encarsia sophia Girault and Dodd (Hymenoptera: Aphelinidae) and Eretmocerus hayati Zolnerowich and Rose (Hymenoptera: Aphelinidae) was evaluated under fluctuating cold storage temperatures. The emergence rate of old pupae of either species was not affected when stored at 12, 10, 8 and 6 &deg, C for 1 week. Cold storage had no effect on the longevity of the emerging adult En. sophia except young pupae stored at 4 &deg, C, while Er. hayati was negatively affected after 2 weeks of storage time at all temperatures. Parasitism by adults emerging from older pupae stored at 12 &deg, C for 1 week was equivalent to the control. Combined with the results for the emergence time, we suggest that the old pupal stage of En. sophia and Er. hayati could be stored at 12 and 10 &deg, C, respectively (transferred every 22 h to 26 &plusmn, 1 &deg, C for 2 h), for 1 week, with no or little adverse effect.

In recent years, fruit flies (Drosophilidae) in cherry treesin northern China have become an increasingly serious problem. In this study, we examined the species composition and dynamics of fruit flies in cherry orchards by lure traps placed at different heights, and in three different cherry cultivarsfrom April through September, between 2014-2016in Qingdao, Shandong Province. The total number of fruit flies increased year by year.Four species were captured: Drosophila melanogaster Meigen, D.suzukii Matsumura, D.hydei Sturtevant, and D.immigransSturtevant. The dominant species wasD. melanogaster, being 66.7% of the total, followed byD. suzukii Matsumura (29.7%). D. hydei and D. immigrans accounted for 3.0 and 0.6%, and for these last two species, no peak period of abundance was observed. In general, drosophilid fruit flies appeeraed inApril, and peakedaround mid-July. Over the three years of the study, peak fruit fly abundance was later each year, being at the end of June in 2014, and in the middle of July in 2015 and 2016. There were significant differences in the number ofDrosophilaspecies among cherry cultivarsas well asin the number of Drosophilatrapped at different heights.The optimal height for trap placement was at 1m above ground level, which is recommended as a standard height for monitoring trap placement.