ORIGINAL PAPER Repellent and acaricidal effects of botanical extracts on Varroa destructor Natalia Damiani & Liesel B. Gende & Matías D. Maggi & Sara Palacios & Jorge A. Marcangeli & Martín J. Eguaras Received: 10 August 2010 / Accepted: 26 August 2010 / Published online: 14 September 2010 # Springer-Verlag 2010 Abstract Extracts of indigenous plants from South America have shown a broad spectrum of bioactivities. No-contaminant and natural substances have recently resurged as control treatment options for varroosis in honey bee colonies from Argentina. The aim of this work was to evaluate the biological activity of botanical extracts from Baccharis flabellata and Minthostachys verticillata on Varroa destructor and Apis mellifera. The acaricidal and insecticidal activities were assessed by the spraying application method. Both ethanolic extracts showed high levels of toxicity against the mites and were harmless to their host, A. mellifera. During the attractive- repellent test, the olfactory stimulus evoked for the extract from B. flabellata resulted as a repellent for mites. The aromatic stimulus of these extracts would be strong enough to cause disturbance on the behavior of V. destructor . Thus, the repellent effect of these substances plus the toxicity on mites postulate these botanical extracts like promising natural compound to be incorporated for the control of varroosis. Introduction Numerous plant-derived substances have demonstrated physiological and behavioral activity against insect pests, and they can provide new sources for the development of natural pesticides (George et al. 2008; Isman 2006). Products with botanical origin have shown a wide range of biological activities including toxicity, repellence, anti- feedant, and growth regulatory properties (Aivazi and Vijayan 2009; Banchio et al. 2003, 2005; Ciccia et al. 2000; Ferrero et al. 2006; Jbilou et al. 2006). Extracts from indigenous plants from South America have shown a broad spectrum antibacterial (Oliveira et al. 2007) and insecticidal activity (Maggi et al. 2005; Palacios et al. 2007; Sosa and Tonn 2008). The genus Baccharis is represented by more than 500 species, distributed mainly in Brazil, Argentina, Colom- bia, Chile, and Mexico (Giuliano 2001). The physico- chemical aspects of the genus have been extensively studied since the early 1900s. More than 150 constituents have been isolated and identified. The main compounds include diterpenoids such as neo-clerodane, although biologically active components like derivates of kauranes and labdanes, phenols and essential oils have been registered (Abad Martinez et al. 2005). Flavones, flavo- noid glycosides, and coumarins and their derivates are the phenolic classes with pharmacological proprieties present in this species (Zdero et al. 1986). The genus has demonstrated to possess a broad spectrum of antioxidant, antimicrobial, antifungal, and antiparasitic activity (Sarkar et al. 2008; Verdi et al. 2005). N. Damiani (*) : L. B. Gende : M. D. Maggi : J. A. Marcangeli : M. J. Eguaras Laboratorio de Artrópodos. Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350 (7600) Mar del Plata, Buenos Aires, Argentina e-mail: ndamiani@mdp.edu.ar N. Damiani : L. B. Gende : M. D. Maggi : S. Palacios : M. J. Eguaras Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Capital Federal, Buenos Aires, Argentina S. Palacios Laboratorio de Química Fina y Productos Naturales, Universidad Católica de Córdoba, Camino a Alta Gracia Km 10 (5000), Córdoba, Argentina Parasitol Res (2011) 108:79–86 DOI 10.1007/s00436-010-2043-3