Host Susceptibility Modulates Pathogenic Potential in the Fungiculture of Higher Attine Ants.

Health and disease emerge from intricate interactions between genotypes, phenotypes, and environmental features. The outcomes of such interactions are context-dependent, existing as a dynamic continuum ranging from benefits to damage. In host-microbial interactions, both the host and environmental conditions modulate the pathogenic potential of a microorganism. Microbial interactions are the core of the agricultural systems of ants in the subtribe Attina, which cultivate basidiomycete fungi for food. The fungiculture environment harbors a diverse microbial community, including fungi in the genus that has been studied as damage-causing agent. Here, we consider the ant colony as a host and investigate to what extent its health impacts the dynamics and outcomes of host- interactions. We found that different ant fungal cultivars vary in susceptibility to the same strains in plate-assays interactions. In subcolony- interactions, while healthy subcolonies gradually recover from infection with different concentrations of conidia, insecticide-treated subcolonies evidenced traits of infection and died within 7 days. The opportunistic nature of infections indicates that diseases in attine fungiculture are a consequence of host susceptibility, rather than the effect of a single microbial agent. By addressing the host susceptibility as a major modulator of pathogenesis, our findings expand the understanding of disease dynamics within attine colonies.