Biocontrol of leucoagaricus gongylophorus of leaf-cutting ants with the mycoparasitic agent trichoderma koningiopsis

Abstract

Leaf-cutting ants are one of the main agricultural and agroforestry pests in the Neotropic region. The essential food source of these ants is Leucoagaricus gongylophorus. Therefore one of the main biocontrol agents under study are Trichoderma species, because of their biocontrol activity against a diverse range of fungi. Here, Trichoderma koningiopsis, isolated from a leafcutting ants nest was tested against three Leucoagaricus gongylophorus strains from leaf-cutting ants by dual culture technique under laboratory conditions. The molecular analysis of ITS sequence data showed three well-separated main clades in which the isolated Trichoderma strain was assembled as a sole subclade among T. koningiopsis strains. The tests also showed that T. koningiopsis strain inhibited the growth of all L. gongylophorus strains tested. The values of radial inhibition of L. gongylophorus ranged from 58% to 69% with an average mean value of 65%. This is the first report on a strain of T. koningiopsis isolated from a naturally parasitized nest of leafcutting ants with biocontrol ability over L. gongylophorus tested in dual culturing method.