|COSTA-JUNIOR, LIVIO - Federal University - Brazil|
|ROSARIO-CRUZ, RODRIGO - Centro Nacional De Investigacion En Cana (CENICANA)|
|Perez De Leon, Adalberto - Beto|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/31/2014
Publication Date: 4/4/2015
Citation: Li, A.Y., Costa-Junior, L.M., Temeyer, K.B., Chauhan, K.R., Rosario-Cruz, R., Perez De Leon, A.A. 2015. Toxicity and repellency of plant essential oils against the arthropod disease vectors Phlebotomus papatasi and Ixodes scapularis. Meeting Abstract Book of the 7th International Conference of Biopesticide. P.44..
Technical Abstract: The sand fly Phlebotomus papatasi is an important blood feeder and the main vector of the trypanosomatid protozoa Leishmania major, which causes leishmaniasis in parts of the Afro-Eurasian region. The black- legged tick Ixodes scapularis is the primary tick vector of the bacterium Borrelia burgdorferi that causes Lyme disease in the United States. Traditional efforts to protect humans from sand fly and tick bites have relied on synthetic chemical pesticides and repellents. However, the extensive use of synthetic pesticides has led to the development of resistance in vector populations, including sand flies and ticks. Additionally, synthetic repellents may work against certain vectors, but not well on other species. New substances with novel modes of action are needed to mitigate the impact of disease vectors. Moreover, natural compounds that are effective and safe offer the opportunity to achieve vector control in a sustainable manner. An international collaboration was established to evaluate the toxicity and repellency of essential oils against P. papatasi and I. scapularis. A glass vial bioassay technique was adapted to determine contact toxicity, and a static air repellency bioassay was used to measure repellency against sand flies. Dose-response relationships were established for the essential oils tested and results were compared to those of permethrin (toxicity) and DEET (repellency). As compared to synthetic pesticides, essential oils in general were not as effective and generally took higher concentrations to achieve 100% mortality. Among the natural products tested, Pimenta dioica essential oil from Mexico was the most effective, causing 100% mortality of adult sand flies after 10 min of exposure at a concentration of 3.9 µg/cm2. Several essential oils, including Citrus aurantium var. amara and Lippia sidoides, were more effective as repellents than DEET when tested at the same concentration (1%) against adult sand flies. Toxicity and repellency data for these essential oils against I. scapularis will reviewed during our presentation. The modes of action of essential oils active against sand flies and ticks remain to be determined. Our hypothesis-driven and science-based approach to try to elucidate the mode of action of key compounds in the bioactive essential oils will be discussed during the presentation.