Atta capiguara leaf-cutter ant

Systematic position: The Atta capiguara species belongs to the family Formicidae and the subfamily Myrmicinae. These leaf-cutter ants are recognized as major agricultural pests in South America, known for their elaborate nesting behavior and highly organized social structure within massive subterranean colonies.

These ants primarily damage grasses and a variety of cultivated crops. They show a strong preference for monocots, frequently causing severe economic losses in sugarcane plantations, pasture grasses, and various cereal crop fields. Their ability to forage over large distances allows them to exploit food sources far from their central nest.

The biology of Atta capiguara is defined by an obligate mutualistic relationship with a specific fungus. Workers harvest fresh leaf material not for direct consumption, but as a substrate to fertilize and grow fungal gardens inside their nests. This specialized nutritional strategy allows the colony to survive and grow steadily under stable subterranean conditions for many years.

Damage assessment shows that these pests can induce rapid and total defoliation of host plants. When a large colony infests a field, the reduction in leaf area prevents effective photosynthesis, leading to stunted development or plant death. Additionally, the construction of deep, extensive tunnel systems causes soil destabilization and disrupts the root systems of agricultural crops.

Integrated Pest Management (IPM) is the most effective approach for control. Key strategies include:

• Application of granular toxic baits that are carried into the nest by workers, ensuring the death of the queen.
• Use of specialized insecticides designed for systemic colony elimination.
• Monitoring of nesting sites to perform targeted interventions before colonies reach massive sizes.