Managing leaf-cutting ants: peculiarities, trends and challenges

Abstract

Leaf-cutting ants are generally recognized as important pest species in Neotropical America. They are eusocial insects that exhibit social organization, foraging, fungus-cultivation, hygiene and a complex nest structure, which render their management notoriously difficult. A lack of economic thresholds and sampling plans focused on the main pest species preclude the management of leaf-cutting ants; such management would facilitate their control and lessen insecticide overuse, particularly the use of insecticidal baits. Recent restrictions on the use of synthetic compounds for such purposes impose additional challenges for the management of leaf-cutting ants. Considerable effort has been exerted regarding these challenges, which are addressed herein, but which also remain challenges that are yet to be conquered.

Toxicity of plant extracts from Bahia, Brazil, to Atta sexdens sexdens workers (Hymenoptera: Formicidae)

“…The sulfuramids (N-ethyl perfluoroctane sulfonamide) and fipronil are the most used active ingredients in ant baits Della Lucia et al, 2014). The sulfuramid, categorized in annex B of the Stockholm Convention on Persistent Organic Pollutants (POPs) as an organic pollutant (United Nations Treaty Collection, 2009), is the most used active ingredient in baits to control leaf cutting-ants, what makes urgent searching for active ingredients to replace it.…”

Screening of native plants from central Argentina against the leaf-cutting ant Acromyrmex lundi (Guérin) and its symbiotic fungus

“…The use of chemical insecticides is also strongly questioned because of the lack of specificity, potential bioaccumulation problems and contamination of ground water and agricultural products (Mugni et al, 2011;Wang et al, 2009). Consequently, alternative methods providing sustainable and efficient control of leaf-cutting ant colonies have been called for (Della Lucia et al, 2014).…”

“…Traditionally, attempts to control leaf-cutting ants have involved the use of chemical insecticides, with only relative success despite continuous applications (Cherret, 1986;Della Lucia et al, 2014;Schoereder et al, 2012). Although thousands of worker ants could be killed by insecticide applications, there is low probability of reaching the queen, a crucial step for colony collapse.…”

New records and new host-parasitoid interactions of phorids (Diptera: Phoridae) parasitizing leafcutter ants (Hymenoptera: Formicidae) in Argentina

“…Their complex social organization and their ability to circumvent most plant's defense mechanisms make controlling them a complex task (Montoya Lerma et al, 2012;Della Lucia et al, 2014). Chemical control, although effective in the short term, poses serious threats to human health and the environment, and more chemicals are added to the lists of banned or restricted pesticides every year, so that producers intending to sell their crops to the European and North American markets have limited options when controlling these pests (Della Lucia et al, 2014). Therefore, alternative methods of pest control have received increased attention, with researchers focusing mainly on biological control either by microorganisms or by other insects (Montoya Lerma et al, 2012;Della Lucia et al, 2014).…”

“…Chemical control, although effective in the short term, poses serious threats to human health and the environment, and more chemicals are added to the lists of banned or restricted pesticides every year, so that producers intending to sell their crops to the European and North American markets have limited options when controlling these pests (Della Lucia et al, 2014). Therefore, alternative methods of pest control have received increased attention, with researchers focusing mainly on biological control either by microorganisms or by other insects (Montoya Lerma et al, 2012;Della Lucia et al, 2014). Amongst the latter, the flies in the family Phoridae have been proposed as promising candidates for biological control of leafcutter ants (Folgarait, 2013) because of two main reasons: their high specificity (Elizalde & Folgarait, 2011) and the indirect effects they have on their hosts, which widely exceed the mortality they inflict (Elizalde & Folgarait, 2012;Guillade & Folgarait, 2014).…”