Screening of natural compounds for the control of nosema disease in honeybees (Apis mellifera)Lara Maistrello1, Marco Lodesani2, Cecilia Costa2, Francesco Leonardi1, Giovanna Marani1, Mauro Caldon3, Franco Mutinelli3 and Anna Granato3
1 Dipartimento di Scienze Agrarie e degli Alimenti, Università di Modena e Reggio Emilia, via G. Amendola 2, Area San Lazzaro - Pad. Besta, 42100 Reggio Emilia, Italy
2 Consiglio per la Ricerca e la sperimentazione in Agricoltura, Unità di Ricerca di Apicoltura e Bachicoltura (CRA-API, ex Istituto Nazionale di Apicoltura), via di Saliceto 80, 40128 Bologna, Italy
3 Istituto Zooprofilattico Sperimentale delle Venezie, viale dell'Università, 10, 35020 Legnaro (Padova), Italy
Received 16 July 2007 - Revised 18 January 2008 - Accepted 4 March 2008 - Published online 25 June 2008
Abstract - The potential of some natural compounds (thymol, vetiver essential oil, lysozyme, resveratrol) for the control of nosema infection in honeybees was evaluated. A first trial aimed at screening substances, in candy preparations, on the basis of their toxicity to honeybees and bees' dietary preferences. None of the tested substances showed an increased bee mortality or decreased bee preference, and were therefore considered suitable for further testing. In the second trial the effects of the natural compounds on nosema diseased honeybees were evaluated: bees were individually dosed with nosema spores and fed candies prepared with the screened substances. The results showed that bees fed with thymol and resveratrol candies had significantly lower infection rates, and bees supplied with resveratrol prepared candy also lived significantly longer. We suggest that thymol and resveratrol could be useful in alternative strategies for the control of nosema disease.
Key words: Nosema / microsporidian / honeybee / thymol / resveratrol
© INRA, DIB-AGIB, EDP Sciences 2008