Honeybees use propolis as a natural pesticide against their major ectoparasite

Pusceddu M.

First

;Annoscia D.

Second

;Floris I.;Frizzera D.;Zanni V.;Angioni A.;Satta A.

Penultimate

;Nazzi F.

Last

2021-01-01

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Abstract

Honeybees use propolis collected from plants for coating the inner walls of their nest. This substance is also used as a natural antibiotic against microbial pathogens, similarly to many other animals exploiting natural products for self-medication. We carried out chemical analyses and laboratory bioassays to test if honeybees use propolis for social medication against their major ectoparasite: Varroa destructor. We found that propolis is applied to brood cells where it can affect the reproducing parasites, with a positive effect on honeybees and a potential impact on Varroa population. We conclude that propolis can be regarded as a natural pesticide used by the honeybee to limit a dangerous parasite. These findings significantly enlarge our understanding of behavioural immunity in animals and may have important implications for the management of the most important threat to honeybees worldwide.