Argentinian Indigenous essential Oils to Control American Fouldbrood in Honeybee Hives

S.FUSELLI,; ROSA, S. G. L.; MARTIN JAVIER EGUARAS; R.FRITZ,; E.GUERZONI,

Bologna

Congreso; Food Micro 2006; 2006

The extensive use of antibiotics and other terapeutic chemical substances to control honeybees diseases lead to accumulation of residues in honey and its by-products, making difficult its marketing. The use of natural substances (e.i. herbs and essential oils) to control bee diseases offers an interesting alternative lessening considerably the risk of antibiotic residues in the world honey supply. AFB is an important disease caused by Paenibacillus larvae, which affects worldwide honey bees colonies, causing great economical loses. In this work, in vitro antimicrobial properties and chemical composition of 8 Argentinean indigenous essential oils against 13 strains of P. larvae, isolated from different localities of Argentine and Italy, were determined. The oils tested were Artemisia absinthium, Artemisia annua, Lepechinia floribunda, Aloysia polystachya, Verbena officinalis, Wedelia glauca, Satureja odora and Hetherothalamus alienus. The antimicrobial activity was evaluated using broth microdilution method. Two way ANOVA results indicated highly significant differences (P< 0.01) for MIC and MBC values between the antimicrobial activity of the essential oils tested. A. absinthium, A. annua and L. floribunda registered the highest inhibitory capacities. The components of these essential oils were identified by GC-MS analyses. They possess strong antimicrobial activity, attributed to the kind and the variation in percentage of the components: á-thujone (62%) was predominant in A. absinthium, artemisia cetone (36%) and 1-8 cineole (31%) constituted the bulk of A. annua and 1-8 cineole (27%), camphene (16%) and camphor (13%) were important in L. floribunda. This is the first report of the use of these indigenous Argentinean plants to in vitro control of P. larvae.