Ixodes scapularis, the blacklegged tick, transmits Borrelia burgdorferi, the agent of Lyme disease. Lyme is the most common vector-borne illness in North America, making it a major concern for human health. I investigated the shrub, Lonicera tatarica, to determine whether this non-native, invasive species is associated with increased tick density. I measured the abundance of blacklegged ticks in in 10x10 m plots with varying densities of Lonicera and native shrubs. Conducting drag sampling and deploying CO2 tick traps in Reist Sanctuary and the Albany Pine Bush Preserve, I concluded L. tatarica does contain higher tick densities compared to other shrub habitats. Other researchers have suggested that the dense vegetation structure of Lonicera shrubs creates a suitable habitat for tick hosts. I further investigated whether allelopathic chemicals secreted by Lonicera could enhance tick survival. Wax worm larvae, Achroia grisella, were used as model organisms and tested under laboratory conditions using a 2x2 factorial design with soil and leaf extract as the main effects. Worm survival was significantly better in the Lonicera soil than in the control soil and survival of worms watered with Lonicera leaf extract was marginally better than the Viburnum (native shrub) extract control. The results from the laboratory experiment paralleled the findings from the field. The investigation suggests that L. tatarica does support high tick density and that allelopathic chemicals may be a mechanism, perhaps by suppressing entomopathogenic fungi. This is the first indication of a possible role for chemical secretions from the plant.
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