English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Eusocial insects interact with a diversity of parasites that can threaten their survival and reproduction. The amount of harm these parasites cause to their hosts (i.e., their virulence) can be influenced by numerous factors, such as the ecological context in which the parasite and its host are inserted. Leaf-cutting ants (genera  Atta ,  Acromyrmex  and  Amoimyrmex , Attini: Formicidae) are an example of a eusocial insect whose colonies are constantly threatened by parasites. The fungi  Escovopsis  and  Escovopsioides  (Ascomycota: Hypocreales) are considered a highly virulent parasite and an antagonist, respectively, to the leaf-cutting ants’ fungal cultivar,  Leucoagaricus gongylophorus  (Basidiomycota: Agaricales). Since  Escovopsis  and  Escovopsioides  are common inhabitants of healthy colonies that can live for years, we expect them to have low levels of virulence. However, this virulence could vary depending on ecological context. We therefore tested two hypotheses: (i)  Escovopsis  and  Escovopsioides  are of low virulence to colonies; (ii) virulence increases as colony complexity decreases. For this, we used three levels of complexity: queenright colonies (fungus garden with queen and workers), queenless colonies (fungus garden and workers, without queen) and fungus gardens (without any ants). Each was inoculated with extremely high concentrations of conidia of  Escovopsis moelleri ,  Escovopsioides nivea , the mycoparasitic fungus  Trichoderma longibrachiatum  or a blank control. We found that these fungi were of low virulence to queenright colonies. The survival of queenless colonies was decreased by  E. moelleri  and fungus gardens were suppressed by all treatments. Moreover,  E. nivea  and  T. longibrachiatum  seemed to be less aggressive than  E. moelleri , observed both  in vivo  and  in vitro . The results highlight the importance of each element (queen, workers and fungus garden) in the leaf-cutting ant-fungus symbiosis. Most importantly, we showed that  Escovopsis  may not be virulent to healthy colonies, despite commonly being described as such, with the reported virulence of  Escovopsis  being due to poor colony conditions in the field or in laboratory experiments.

Low Virulence of the Fungi Escovopsis and Escovopsioides to a Leaf-Cutting Ant-Fungus Symbiosis