Juvenile Hormone I Effects on the Camel Tick, Hyalomma Dromedarii (Acari: Ixodidae)1, 2

Feeding and engorged nymphs and unfed and feeding adults of Hyalomma (H.) dromedarii were treated topically with 10, 20, and 50 μg juvenile hormone I (JH I). Large doses of JH I were lethal to adults; nymphs tolerated JH I, but emerging adults exhibited delayed mortality, which occurred after attachment to the host. The premolting period was prolonged by 9.4 to 31.0% in nymphs treated on repletion day but not in those treated at other times. JH I did not alter adult sexual behavior and caused only a small reduction in fertility of both sexes. The results suggest that H. dromedarii systems did not respond toJH I because it may be very different from tick JH and/or the administration method was unsuitable.