TEMPERATURE-DEPENDENCE IN LOCOMOTION OF THE PARASITOID APHELINUS-ASYCHIS (HYMENOPTERA, APHELINIDAE) FROM GEOGRAPHICAL REGIONS WITH DIFFERENT CLIMATES

In biological control, introduction of insect agents from regions with similar climatic conditions to those of the target host habitat have been an important consideration for successful implementation. Yet, th ere is little documentation of genetic variation in response to climat e among natural enemy populations. In experiments on Aphelinus asychis Walker collected from China France, and Morocco for release against D iuraphis noxia (Mordvilko) in North America, the relationship between locomotion (i.e., mean and maximum walking speeds and proportion of ti me walking) and temperature did not differ among geographical regions with different climates. Mean and maximum walking speeds increased wit h temperature from 8.5 to 28.5 degrees C. Mean walking speed increased with hind tibia length, and because hind tibia length varied among ge ographical regions, it was used as a covariate in analyses comparing r egions. Our results suggest that although locomotion depended on tempe rature, this dependence has not led to selection for adaptation to dif ferent temperature regimes. Thus, for mean and maximum walking speeds and proportion of time walking, insects collected from all 3 geographi cal areas were suited to the same climate.