The chemical battle in ants' fungus gardens

Abstract

Millions of years before humans began cultivating plants, ants were already practicing agriculture. In a special chamber of the anthill, ants cultivate the mycelium of a fungus, which they feed with fresh leaf fragments. Thanks to this plant biomass, the fungus grows and, as a reward, produces sugarrich structures called gongylidia, which the ants feed their larvae. The cultivated mycelium is not free from threats, as its enemies are other fungi that try to feed on it. To defend their crops, the ants rely on bacterial allies that produce secondary metabolites, organic molecules that eliminate the invading fungus. In the ant garden, a real chemical battle is waged. While the pathogenic fungus produces metabolites to colonize the crop, the ants' bacterial allies produce compounds to combat it. Modern human agriculture has imitated this model, incorporating the use of bacteria and fungi to protect its crops from pathogenic microorganisms. This natural model, which does not harm the health of ants, other species, or the ecological environment, inspires us to develop more environmentally friendly agricultural practices.