Leaf-cutting Ants Research Articles

The interplay between leaf-cutter ants behaviour and social organization

AbstractLeaf-cutter ants (Atta and Acromyrmex species) exhibit complex social organizations that have fascinated scientists for decades. The leaf-cutter ants belong to a subgroup of fungus-growing ants, which live with fungus inside their nests. The behaviours exhibited by these ants are closely linked to their social organization, which involves intricate division of labour, caste systems, and cooperative tasks. This review article provides an overview of the behaviors associated with the social organization of leaf-cutter ants. It explores various aspects of their social organization, including foraging behavior, hitchhiking behaviour, hygienic behaviour, social organization and environmental influences. The leaf cutter ants have the instinct to forage, as they walk around the nest to cut leaf fragments from plants, then transport those fragments with their jaws and go back to the nest to cultivate a special fungus garden within the colony. By synthesizing existing knowledge, this review highlights the intricate relationships between behaviors and the social structure of leaf-cutter ants, shedding light on the underlying mechanisms and evolutionary implications. Furthermore, it identifies research gaps and proposes future directions for studying leaf-cutter ant behaviors, including emerging techniques and interdisciplinary approaches. The behaviors correlating with the social organization of leaf-cutter ants showcase the intricate mechanisms underlying their highly organized societies. In conclusion, this review contributes to our understanding of the fascinating behaviors exhibited by leaf-cutter ants and their implications in the broader context of social insect societies.

Landscape configuration modulates the presence of leaf-cutting ants in eucalypt plantations

Pest responses to landscape complexity show variable patterns globally, primarily related to species traits and specific managed habitats. Leaf-cutting ants (LCAs) are native insects and important pests of plantation forests in South America. We evaluated the responses of LCA nests in young Eucalyptus plantations to different spatial contexts: land uses, interfaces (adjacent land use pairs), agroecosystems, and landscapes. We selected 30 sites in the littoral region of Argentina representing three types of land uses neighboring Eucalyptus plantations: adult eucalypt plantations, citrus plantations, and semi-natural habitats. At each site, we quantified and identified LCA nests and characterized landscape composition and configuration in circles of 250 m radius. LCA nest abundance and presence were similar across different land uses, interfaces, and agroecosystems. Nest presence decreased in landscapes with increasing mean perimeter/area ratio and citrus coverage, whereas LCA abundance showed a similar trend. This indicates that heterogeneous landscapes and those with greater citrus plantation coverage were less likely to have LCA nests. Our findings suggest that landscape configuration was the main predictor of the LCA presence. Understanding the dynamics of LCAs populations and their complex associations with landscape components will contribute to developing successful environmental pest management strategies for plantation forests.

Three cuticular amides in the tripartite symbiosis of leafcutter ants.

Cuticular hydrocarbons (CHCs) play various roles in insects' chemical ecology. As leafcutter ants live in a specific symbiosis with fungi, they harvest and with different bacteria, some of these CHCs might be associated with a mutualistic function within this symbiosis. To obtain a more precise picture in that respect we compared the CHC profiles of the leafcutter ants, Atta sexdens, Atta cephalotes, and Acromyrmex octospinosus inhabited by mutualistic bacteria with the profiles of Polyrhachis dives and Messor aciculatus by GC-EI-MS analysis and 28 other ant species by data from the literature. We were able to identify three alkyl amides (hexadecanamide, hexadecenamide, and tetradecanamide), occurring only in the CHC profiles of leafcutter ants inhabited by symbiotic bacteria. Our results lead to the conclusion that those alkyl amides could have a function in the tripartite symbiosis of leafcutter ants.

Agroforestry improves soil fauna abundance and composition in the Atlantic Forest of Paraguay

Edaphic fauna is a major determinant of agricultural soil quality, but few studies have investigated soil fauna in different agroforestry systems. The objective of this study was to evaluate the effect of agroforestry plantations of Ilex paraguariensis on the abundance and composition of ants, earthworms, and nematodes in two agronomic systems, conventional and agroecological, and three plantation types (pathsides, agricultural field edges, and islets) in the Atlantic Forest in Paraguay. The study was conducted on 26 plots distributed in the different agronomic systems and plantation types (three plots per combination of agronomic system and plantation type, with a total of 18 plots, plus eight control plots). We compared agroforestry plots with non-agroforestry plots and with natural forests. Eighteen individuals of different native species (Cordia americana, Cedrela fissilis, Handroanthus impetiginosus, Handroanthus albus, Peltophorum dubium, and Cordia trichotoma) were planted in each plot, together with five individuals of I. paraguariensis (total of 2300 individuals ha−1). The agroforestry scheme increased the abundance and improved the composition of beneficial soil fauna in the two agricultural systems. The agroecological system showed 238% higher abundance of ants and 90% higher abundance of earthworms than the conventional one. In both systems, the agroforestry scheme led to lower abundance of deleterious Atta sexden and Acromyrmex spp. leafcutter ants and higher abundance of beneficial species. The three plantation types increased the abundance of beneficial species. Agroforestry plots, particularly those in an agroecological system, were more similar to reference forest than to non-agroforestry plots. Our results suggest that the composition of soil fauna at the study site was significantly affected by the agroforestry scheme and, agronomic system, but not by plantation type. These results support the advantages of agroforestry and agroecological systems for favoring the diversity of soil fauna and related ecosystem services, which may help guide the design of successful agroforestry interventions.

Formicidal Potential of Thymol Derivatives: Adverse Effects on the Survival and Behavior of Acromyrmex balzani

Leaf-cutting ants are important pests of agricultural and forest crops. Currently, few insecticides are registered for the control of these insects. Natural bioactive molecules can serve as models for the synthesis of new insecticidal compounds. Such ant killer products must be sustainable and efficient, considering not only lethal effects, but also sublethal effects, which can interfere with behavior and communication between colony members. In this study, we analyzed the toxicity of the monoterpene thymol and its derivatives, as well as the sublethal effects of these compounds on the behavior of the leaf-cutting ant Acromyrmex balzani. These effects were compared with the conventional synthetic insecticide deltamethrin. Although deltamethrin showed higher toxicity (LD50 = 0.87 × 10−5 µg/mg), all other tested compounds increased ant mortality, with thymyl chloroacetate being the most toxic derivative (LD50 = 1.41 µg/mg), followed by thymol (LD50 = 2.23 µg/mg). These three most toxic compounds interfered differentially in the behavior of ants. Thymyl chloroacetate caused increased self-cleaning and reduced allogrooming, which may be related to an attempt to avoid contamination between nestmates. In general, thymol caused greater avoidance among ants, reduced walking speed and caused disorientation in workers. On the other hand, thymyl chloroacetate (LD30) considerably increased the walking speed of the group, without changing the orientation of the individuals. Such changes may interfere with basic activities such as foraging and altering colony cohesion via different mechanisms. Thus, despite the desirable effects of deltamethrin on ant control, this insecticide is highly toxic and should be discontinued soon. Our results show that thymol and its structural modification in thymyl chloroacetate may represent potential ant killers to be used in the management of A. balzani.

Strong positive allometry of bite force in leaf-cutter ants increases the range of cuttable plant tissues.

Atta leaf-cutter ants are the prime herbivore in the Neotropics: differently sized foragers harvest plant material to grow a fungus as a crop. Efficient foraging involves complex interactions between worker size, task preferences and plant-fungus suitability; it is, however, ultimately constrained by the ability of differently sized workers to generate forces large enough to cut vegetation. In order to quantify this ability, we measured bite forces of Atta vollenweideri leaf-cutter ants spanning more than one order of magnitude in body mass. Maximum bite force scaled almost in direct proportion to mass; the largest workers generated peak bite forces 2.5 times higher than expected from isometry. This remarkable positive allometry can be explained via a biomechanical model that links bite forces with substantial size-specific changes in the morphology of the musculoskeletal bite apparatus. In addition to these morphological changes, we show that bite forces of smaller ants peak at larger mandibular opening angles, suggesting a size-dependent physiological adaptation, probably reflecting the need to cut leaves with a thickness that corresponds to a larger fraction of the maximum possible gape. Via direct comparison of maximum bite forces with leaf mechanical properties, we demonstrate (i) that bite forces in leaf-cutter ants need to be exceptionally large compared with body mass to enable them to cut leaves; and (ii), that the positive allometry enables colonies to forage on a wider range of plant species without the need for extreme investment in even larger workers. Our results thus provide strong quantitative arguments for the adaptive value of a positively allometric bite force.

Draft Genome Sequence of Novel Streptomyces sp. Strain AJ-1, Isolated from a Leafcutter Ant in Uttarakhand, India.

We present the draft genome sequence of Streptomyces sp. strain AJ-1, which was isolated from a leafcutter ant found in Uttarakhand, India. The genome assembly resulted in 43 contigs, with a combined length of 6,948,422 bp and a GC content of 73.5%. Through genome annotation, we identified 5,951 protein-coding genes and 67 tRNA genes.

The Family Megachilidae (Hymenoptera: Apoidea) In Pollination Ecology- a Review

Family Megachilidae belongs to cosmopolitan family groups, making nests in the soil, and mostly prefer pre-existing cavities such as pithy stems, galls, and dead wood for nesting. Mostly they are solitary, long-tongued, and have pollen-collecting structure scopa present on the ventral side of the abdomen rather than hind legs (mostly in other bees). Genus Megachilid is generally known as leaf cutter and mason bees. Family Megachilidae is characterized by different groups of the bees such as solitary, mason, resin, carder, and leafcutter bees, and are the most important pollinators for agricultural, horticultural, medicinal, and aromatic plants. Female leafcutter bees have a special character to form brood cells by using their mandibles to cut leaves. Family Megachilidae is found throughout the world except for Antarctica, lowland tropical rain forests, deserts, and hilly ecosystems, and 238 species are listed from the Indian region. Our review is based on the significant role of the family Megachilidae and their different adaptive structures and behaviour to enhance their contribution to the pollination ecology.

How leaf-cutting ants gauge leaf portion size

They might not be able to leap tall buildings with a single bound, but leaf-cutting ants are insect superheroes, capable of carrying leaf pieces up to six times their body mass to cultivate fungus in their borrows. But how do the charismatic creatures determine the size of the fragments they carve with their mandibles? Do they use their bodies as a simple ruler, or do they use information about the position of their bodies to adjust how far they cut, adapting to the thickness of a leaf while dismembering it? Knowing that the insects alter the trajectory of a cut when sculpting ®Parafilm of different thicknesses, Flavio Roces from the University of Würzburg, Germany, decided to find out how the ants govern the size of the portions they trim. But first he, Daniela Römer and Rebecca Exl (also from University of Würzburg) needed to get to grips with how the insects snip out regular leaf fragments.Exl fashioned fake leaves from ®Parafilm – one layer for thin leaves (0.13 mm), three for thick leaves (0.38 mm) – rubbed them with crushed bramble leaves or rose oil to make them more appealing to the ants and installed them in the foraging area of a lab-based Atta sexdens ant colony. As soon as an ant climbed aboard, Exl retrieved the pseudoleaf and positioned it in front of a camera to record the ant's manoeuvres.Initially, the ant lay along the edge of the leaf, with the hind and middle leg on the side nearest the edge gripping the ®Parafilm. Then, it snipped upward, gradually rotating its body until upright as it cut in an arc, attaching the second hind limb when its body was almost vertical. As the ant continued cutting, it rotated further, eventually releasing the first hind limb from the leaf edge while still holding on with the second hind limb, until it severed the chunk by cutting through the leaf edge after swivelling the body through 180 deg. And when Exl compared the ants’ posture as they cut through thick and thin leaves, she realised that they adapted their technique, crouching their legs to reduce their reach to cut smaller elliptically shaped fragments when provided with thick leaves.But how were the ants controlling the size of the fragments they incised? Could knowledge about the position of their hind legs gripping the leaf edge guide their cutting trajectory? This time, Exl waited until each ant was halfway through a cut before gently inserting a piece of paper between the ant and the fake leaf to release its grip as it continued snipping. Without knowledge of the position of their legs relative to the leaf edge, some of the ants cut smaller elliptical portions. They were using information provided by their hind legs gripping the leaf edge to guide the trajectory of their cut. However, some ants were still able to cut similarly sized fragments. Were they using some other sensory information to guide their trajectory? Could hairs at the front of the neck, which detect the position of the head, contribute to their sense of cutting direction?Exl cautiously shaved off these hairs and allowed the ants to cut a ®Parafilm leaf while gently detaching the insect's limbs from the edge with the paper guard, and this time the ants completely lost track of direction, producing randomly shaped fragments that were nothing like the elliptical pieces they had cut previously. Leaf-cutting ants depend on knowledge of the position of their hind legs gripping the leaf edge and the position of their head to keep them cutting on the curve and ensure that they never cut fragments that exceed their exceptional strength.

Two feedback mechanisms involved in the control of leaf fragment size in leaf-cutting ants.

Polymorphic leaf-cutting ants harvest leaf fragments that correlate in size with the workers' body size. When cutting, workers anchor their hind legs on the leaf edge and rotate, removing approximately semicircular fragments. Workers show behavioural plasticity and modify their leg extension while holding onto the leaf edge depending on, for instance, leaf toughness, cutting smaller fragments out of tough leaves. What sensory information workers use to control the cutting trajectory remains unknown. We investigated whether sensory information from both the leg contact with the leaf edge and from head movements underlies fragment size determination. In the laboratory, we recorded Atta sexdens workers cutting standardised ®Parafilm pseudoleaves of different thickness, and quantified cutting behaviour and body reach, i.e. the distance between the mandible and the anchored hind leg tarsus. Experimentally preventing contact with the leaf edge resulted in smaller fragments, evincing that workers control the cutting trajectory using information from the contact of the hind legs with the leaf edge. However, ants were able to cut fragments even when contact of all six legs with the edge was prevented, indicating the use of additional sensory information. Ablation of mechanosensory hairs at the neck joint alone did not influence fragment size determination, yet simultaneously preventing sensory feedback from both mechanosensory hairs and edge contact led to a loss of control over the cutting trajectory. Leaf-cutting ants, therefore, control their cutting trajectory using sensory information from both the leg contact with the leaf edge and the lateral bending of the head.

Developmental biomechanics and age polyethism in leaf-cutter ants.

Many social insects display age polyethism: young workers stay inside the nest, and only older workers forage. This behavioural transition is accompanied by genetic and physiological changes, but the mechanistic origin of it remains unclear. To investigate if the mechanical demands on the musculoskeletal system effectively prevent young workers from foraging, we studied the biomechanical development of the bite apparatus in Atta vollenweideri leaf-cutter ants. Fully matured foragers generated peak in vivo bite forces of around 100 mN, more than one order of magnitude in excess of those measured for freshly eclosed callows of the same size. This change in bite force was accompanied by a sixfold increase in the volume of the mandible closer muscle, and by a substantial increase of the flexural rigidity of the head capsule, driven by a significant increase in both average thickness and indentation modulus of the head capsule cuticle. Consequently, callows lack the muscle force capacity required for leaf-cutting, and their head capsule is so compliant that large muscle forces would be likely to cause damaging deformations. On the basis of these results, we speculate that continued biomechanical development post eclosion may be a key factor underlying age polyethism, wherever foraging is associated with substantial mechanical demands.

Management of ant pests in urban environments

Ants (Hymenoptera: Formicidae) are social insects and important pests in the urban environment. The main groups of pest ants in the urban environment are leafcutter and house ants. Leaf-cutter ants cause crescent-shaped defoliation of plants, where in the urban environment it causes problems in gardens and ornamental plants. Domestic ants cause human health problems, contaminate food and cause problems in equipment and buildings. In this work, we propose an integrated ant management program in urban environments. For that, a bibliographic review was carried out addressing the following topics: life cycle of ants, main groups of pest ants, factors that influence their attack, decision-making systems, management strategies and tactics. It is observed that ants are pests that are difficult to control, and successful control is related to the correct execution of the various components of integrated pest management. Regarding control tactics, chemical control is the main method used to control ants in urban environments because the effectiveness of other methods (ie, biological and behavioral control) is poor.

Entomopathogenic Strains of the Fungus Purpureocillium lilacinum Damage the Fungus Cultivar of Pest Leaf-Cutter Ants.

Purpureocillium lilacinum (Hypocreales: Ophiocordycipitaceae) is a cosmopolitan fungus not only pathogenic to insect and nematode hosts but also to other fungi. Although having one organism with multiple effects would be desirable in a biocontrol strategy, few studies have looked at the multiple roles one strain could play. This work shows how three strains of P. lilacinum, previously proven to be entomopathogenic to leaf-cutter ants (LCA), could degrade several strains of Leucoagaricus sp., the fungus cultivated by LCA as their food source. We isolated four strains of Leucoagaricus sp. from Acromyrmex and Atta LCA species, and we determined their species molecularly, as well as their clade identity (Leucoagaricus gongylophorus, clade-A). We observed the effects on growth rates on Petri dishes and the interaction of microscopic structures of both fungi on slides. All three P. lilacinum strains inhibited the growth of L. gongylophorus. They also degraded all L. gongylophorus isolated from the Acromyrmex species, causing hyphae expansion and degradation of the cell wall. However, only one of them succeeded in degrading the L. gongylophorus strain isolated from the Atta species. The results confirm the damage to the hyphae of ant cultivars and highlight the need for future studies that reveal whether such behavior is due to P. lilacinum's mycoparasitic behavior. Using a single P. lilacinum strain with a dual function that includes the degradation of the cultivar of LCA of both genera would be a very promising strategy for the biocontrol of one of the worst herbivore pests in the Neotropics.

AntTracker: A low-cost and efficient computer vision approach to research leaf-cutter ants behavior

Leaf-cutter ants play a crucial role in agroecosystems, and understanding their behavior is key to developing effective damage control strategies. While several tracking solutions exist for ants in controlled environments or on aerial images, accurately measuring ant behavior in the wild remains a challenge. In this work, we propose a three-stage processing pipeline that segments individual ants, tracks their movement, and classifies whether they are carrying a leaf using a convolutional neural network. The output of the pipeline includes a timestamped record of the activity on the trail, accounting for parameters such as ant velocity, size and if it is going from or to the nest. We use the recently developed portable device AntVideoRecord to register video of a selected ant trail. To validate our approach, we collected a labeled dataset and evaluated each stage using standard metrics, achieving a median F2 score of 83% for segmentation, MOTA of 97% for tracking and F1 of 82% for detecting ants carrying a leaf. We then carried out a larger use case in the wild, demonstrating the effectiveness of our approach in capturing the intricate behaviors of leaf-cutter ants. We believe our method has the potential to inform the development of more effective ant damage control strategies in agroecosystems.

Dietary diversity, sociality, and the evolution of ant gustation

Ants have remarkably diverse diets and extraordinary species richness, making them an excellent model system to study the evolution of taste. In this entirely eusocial clade, food choice and the mechanisms that regulate feeding have both individual and social dimensions. How taste receptors and sensory processing drive food preferences to generate dietary breadth in ants is poorly understood. It is additionally unclear how elements of colony organization such as division of labor and social food flow impact the mechanistic basis and evolution of taste. Previous work on dipteran, lepidopteran, and hymenopteran gustatory systems, while foundational, provide limited insights into ant dietary specialization. Here we synthesize and analyze research on ant gustation to identify mechanisms, sociobiological correlates, and phylogenetic patterns. We discuss the current state of genomic analyses of taste and future research. We propose that strikingly polymorphic species of Pheidole, Cephalotes, Camponotus, and leafcutter ants (Atta and Acromyrmex) offer compelling social systems to explore adaptive variation in gustation because of their pronounced division of labor in which morphologically, behaviorally, and neurally differentiated workers vary in feeding behavior. Research on ant gustation within and among species will advance our understanding of sensory systems and provide insight into the impact of taste on the evolution of species diversity and how social organization influences gustation.

Fungal Community Associated with the Leaf-Cutting Ant Acromyrmex crassispinus (Hymenoptera: Formicidae) Colonies: a Search for Potential Biocontrol Agents.

The leaf-cutting ant Acromyrmex crassispinus is considered an important pest in forest plantations in southern Brazil. This work aimed to study the fungal community associated with A. crassispinus colonies, subjected to treatments with subdoses of granulated baits (sulfluramid), which might reduce the ability of the ants to care for their symbiotic fungus and other fungi (maybe biocontrol fungi) would take over, to prospect for potential biological control agents. Samplings of fungus gardens and dead ants allowed the identification of 195 fungal isolates, distributed in 29 families, 36 genera, and 53 species. The most frequent genera were Trichoderma (49.2%), Penicillium (13.8%), Chaetomium (6.2%), and Fusarium (3.6%). This is the first study that conducted a survey of antagonistic and entomopathogenic fungi to A. crassispinus and its symbiotic fungus, reporting for the first time the occurrence of potential biological control agents. Escovopsis weberi, Fusarium oxysporum, Rhizomucor variabilis, Trichoderma atroviride, Trichoderma harzianum, Trichoderma koningiopsis, and Trichoderma spirale are considered some of the potential biocontrol organisms.

Contamination and mortality of leaf-cutting ant workers by the quinone inside inhibitor fungicide after social interactions

Leaf-cutting ants of the genera Atta and Acromyrmex (Hymenoptera: Formicidae) are the most important pests in forest and agricultural plantations and livestock. Toxic baits are the main method to manage these insects. The objective was to determine whether the behavior of allogrooming, touch, and self-grooming among Atta sexdens rubropilosa Forel, 1908 (Hymenoptera: Formicidae) workers disperse the fungicide quinone inside inhibitor and whether this product is toxic to them. This fungicide was applied, topically, in groups of workers and the social interactions between them and their mortality with and without the fungicide were evaluated. The interactions and the quinone inside inhibitor fungicide contamination increased with the number of leaf-cutting ant workers per group. Excessive touches, with subsequent allogrooming, and self-grooming among the ant workers dispersed the quinone inside the inhibitor fungicide causing 100% mortality and indicating its toxicity to this insect. The hypothesis that social interactions contaminated ant colony mates and the toxicity of the fungicide quinone inside inhibitor to workers of the leaf-cutting ant A. sexdens rubropilosa was proven.

Herbivory by Atta vollenweideri: Reviewing the significance of grass-cutting ants as a pest of livestock.

The grass-cutting ant Atta vollenweideri is well suited for studies examining the negative effect leaf-cutting ants have on livestock production in South American grasslands because they forage on the same plants as cattle. This study investigated the impact of A. vollenweideri on livestock production in Argentinean rangelands. First, we assessed A. vollenweideri herbivory rates and its economic injury level (EIL). Second, using satellite imagery in a region covering 15,000 ha, we estimated the percentage of this area that surpassed the calculated EIL. Results showed that A. vollenweideri consumed approximately 276kg of dry plant weight/ha/year, foraging mostly on grasses (70%). Additionally, ants cut 25% of herbs and 5% of trees. In summer and autumn, ants consumed more grasses, while in winter and spring, herbs and trees were also significantly cut. Ants consumed 7% of the forage demand needed to raise a calf according to the management regime applied by farmers. Our calculated EIL (5.85 nests/ha) falls in the range of previous studies. Colonies were absent in 93.6% of the surveyed area, while their density was below the EIL in 6.2% of the area. A. vollenweideri populations surpassed the EIL in only 0.2% of the area, which corresponds to 2.6% of the locations holding colonies. These results question the perception that Atta leaf-cutting ants are a pest of livestock production. Although ants consume a small percentage of cattle's forage demand, evidence that ants and cattle are competing in the few cases in which density surpasses the EIL is arguable. First, grass-cutting ants are capable of consuming herbs and trees in addition to the grasses on which cattle mostly feed. Second, there is no evidence indicating that both are cutting the same plant portions when preferences overlap. Third, evidence suggests that ants are not displaced under high-pressure grazing regimes by cattle. In the countries where A. vollenweideri is present, decision makers have promulgated several acts making its control mandatory. It is time to revisit the pest status of A. vollenweideri and include the use of EIL as a control criterion.

Limited impacts of the fungus Syncephalastrum on nests of leaf-cutting ants

Limited impacts of the fungus Syncephalastrum on nests of leaf-cutting ants

Repellent Effect of Leaf-Cutting Ant Waste Against the Aphid Lipaphis erysimi (Kaltenbach)

Most conventional methods for controlling agricultural pests cause environmental problems. Thus, sustainable pest management methods have been constantly sought and tested in recent years. The waste substrate produced by leaf-cutting ants (referred to as ‘nest refuse’) is reported to be repellent to their own foraging. This substrate is avoided by leaf-cutting ants because it presents chemical and physical warning signs to the ants in addition to possible pathogens. In the present study, we experimentally analyzed whether a liquid formulation prepared with the discarded substrate produced by leafcutting ants of the species Acromyrmex balzani and Atta opaciceps would be repellent to the aphid Lipaphis erysimi. A total of 103 bioassays were carried out in petri dishes of Ꝋ = 150 mm, with two leaf discs of Brassica oleracea L. (var. acephala) sprayed with the control solution (water/alcohol 50%) or with the extract of the nest refuse of one of the ant species. Bioassays were compared using binomial analysis. Ant waste extracts from both species were efficient in repelling aphids (P < 0.05). New studies can help fill in the gaps found, such as the identification of substances potentially causing the effect, the duration of the effect, and the dosage and adequate amounts of extract to be applied, as well as other crops to be protected, and other pests to be repelled.