title: Survival of Atta sexdens workers on different food sources.
abstract: Leaf-cutting ants belonging to the tribe Attini are major herbivores and important agriculture pests in the neotropics, these ants being thought to feed on the sap which exudes from the plant material which they cut and also on the mycelium of a symbiotic fungus that grows on plant material inside their nests in what is called "the fungus garden". However, we have found that the survival of Atta sexdens worker ants on leaves, on mycelium of the ants' symbiotic fungus, Leucoagaricus gongylophorus, or on plant polysaccharides was the same as that of starved A. sexdens, while, conversely, significantly longer survival was achieved by ants fed on the fungus garden material or on some of the products (especially glucose) of the hydrolysis of plant polysaccharides. We found that the fungus garden contained glucose at a higher concentration than that found in leaves or fungal mycelium, and that this glucose was consumed by the ant to the extent that it was probably responsible for up to 50% of the nutritional needs of the workers. The fungus garden contained polysaccharide degrading enzymes (pectinase, amylase, xylanase and cellulase) in proportions similar to that observed in laboratory cultures of L. gongylophorus. It thus appears that A. sexdens workers obtain a significant part of their nutrients from plant polysaccharide hydrolysis products produced by the action of extracellular enzymes released by L. gongylophorus. In this paper we discuss the symbiotic nutrition strategy of A. sexdens workers and brood and the role played by plant polysaccharides in the nutrition of attine ants.
authors.affiliation: Instituto de Biociências, Centro de Estudos de Insetos Sociais, Universidade Estadual Paulista, Av. 24-A, 1515, CEP 13506-900, Rio Claro, SP, Brazil.
authors.forename: Aline
authors.initials: A
authors.lastname: Silva
authors.forename: Maurício
authors.initials: M
authors.lastname: Bacci
authors.forename: Célia
authors.initials: C
authors.lastname: Gomes de Siqueira
authors.forename: Odair
authors.initials: O
authors.lastname: Correa Bueno
authors.forename: Fernando Carlos
authors.initials: FC
authors.lastname: Pagnocca
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Aparecida Hebling
mesh_terms: D000818:Animals; D001000:Ants / Q000502:physiology*; D004032:Diet; D005658:Fungi / Q000737:chemistry / Q000502:physiology; D005947:Glucose / Q000378:metabolism; D025282:Mycelium / Q000378:metabolism; D018515:Plant Leaves; D011134:Polysaccharides / Q000378:metabolism; D015996:Survival Rate; D013559:Symbiosis
chemical_list: D011134:Polysaccharides; D005947:Glucose