Disease management in two sympatric Apterostigma fungus-growing ants for control the parasitic fungus Escovopsis

<p>Antagonistic interactions between host and parasites are often embedded in networks of interacting species, in which hosts may be attacked by competing parasites species, and parasites may infect more than one host species. To better understand the evolution of host defenses and parasite counter defenses in the context of a multihost, multiparasite system, we studied two sympatric species, of congeneric fungus-growing ants (Attini) species and their symbiotic fungal cultivars, which are attacked by multiple morphotypes of parasitic fungi in the genus, <i>Escovopsis</i>. To assess whether closely-related ant species and their cultured fungi are evolving defenses against the same or different parasitic strains, we characterized <i>Escovopsis </i>that were isolated from colonies of sympatric <i>Apterostigma dentigerum</i> and <i>A</i>. <i>pilosum. </i>We assessed <i>in vitro </i>and <i>in vivo</i> interactions of these parasites with their hosts. While the ant cultivars are parasitized by similar <i>Escovopsis</i> spp., the frequency of infection by these pathogens differs between the two ant species. The ability of the host fungi to suppress <i>Escovopsis</i> growth, as well as ant defensive responses towards the parasites, differ depending on the parasite strain and on the host ant species.</p>