Spores of Beauveria bassiana and Trichoderma lignorum as a bioinsecticide for the control of Atta cephalotes

Abstract

Background The leafcutter ant (Atta cephalotes) is associated with losses in the agricultural sector, due to its defoliating activity; for its control, biological, mechanical and chemical methods have been developed, the latter associated with adverse effects on human and environmental health. This research validated in the field for the control of the leafcutter ant (A. cephalotes) using a mixture of Beauveria bassiana and Trichoderma lignorum spores. Methods The effectiveness from the combination of spores of B. bassiana and T. lignorum with an initial concentration of 2 × 109 spores/ml, in the following proportions of B. bassiana and T. lignorum, A (1:1), of each fungus. It was evaluated within the university campus, comparing it with two commercial formulations, Mycotrol (B. bassiana) and Mycobac (T. lignorum). Additionally, this formulation was evaluated in 49 nests distributed 16 in 14 locations in Colombia. The formulation application was carried out by direct application, using a pump at a speed of 10 ml/m2. The effectiveness was estimated from the reduction of the flow of ants, evaluating the statistically significant differences using the ANOVA and Tukey-test. Results Effective control of 90% of the nests was observed in the field phase in 60 days, except in nests with areas > 50 m2 that were located in regions with high rainfall (annual average precipitation above 7000 mm), such as Buenaventura. Conclusions In this work, it was demonstrated that the combination of B. bassiana and T. lignorum spores represent a viable alternative for the control of the leafcutter ant, in which the effectiveness is related to several factors, including the size of the nest and the rainfall in the area.

Beauveria bassiana secondary metabolites: a review inside their production systems, biosynthesis, and bioactivities

“…It colonizes the hemocoel consuming the nutrients of the hemolymph as well as secreting toxins that contribute to the modification of its structural integrity by inhibiting the selective process or its enzymes besides interfering with its regulatory system accelerating the death of the insect. Once the insect is dead, the cuticle is breached again from the inside out in order to emerge conidiophores that sporulate on the body of the insect and can begin the infection in other arthropods by spreading the spores (Borges et al, 2010;Mascarin & Jaronski, 2016;Valero-Jiménez et al, 2016;Daza et al, 2019;Litwin et al, 2020) The production of specific pigments confer to the spores resistance to ultraviolet radiation, and to environmental conditions that could be detrimental to the fungus (Chintapenta et al, 2014). The infection process lasts up to 14 days and depending on the fungal species the first symptoms of infection occur 7 days after the first contact of the fungus with the insect (Litwin et al, 2020).…”

Genome-Wide Identification and Analysis of Nilaparvata lugens microRNAs during Challenge with the Entomopathogenic Fungus Metarhizium anisopliae

“…The use of chemicals imposes significant negative effects on species diversity and the well-being of ecosystems [ 5 , 49 ]. Alternative control tools, such as entomopathogenic fungi, present good potential for the insect pest control under both greenhouse and large-scale field conditions [ 23 , 50 ]. The entomopathogenic fungus M. anisopliae has been used for the control of several insect pests, including the major rice pests.…”

Preservative Media for Beauveria Bassiana (bals.) Vuill Storage

“…Rojas et al (2018) recorded a mortality percent of 84.48% after 6 days of Solenopsis invicta workers treatment by B. bassiana. Daza et al (2019) mentioned that an effective control of 90% of the nests was observed in the field phase in 60 days when they evaluated a bioinsecticide composed of the spores of B. Bassiana and Trichoderma lignorum for the control of the leafcutter ant (Atta cephalotes) under field conditions.…”