Purpureocillium takamizusanense: A New Entomopathogenic Fungus in the Americas and Its Pathogenicity Against the Cacao Black Bug, Antiteuchus tripterus (Hemiptera: Pentatomidae)

Hernandez-Diaz E.; Martínez L.C.; Díaz-Valderrama J.R.; Cumpa-Velasquez L.M.; Oliva-Cruz S.M.; Huaman-Pilco A.F.; Rubio K.; León-Alcántara E.E.; Ix-Balam M.A. · Agronomy (2025) · DOI: 10.3390/agronomy15102315

Resumen

The black bug, Antiteuchus tripterus (Hemiptera: Pentatomidae), is one of the most important pests of cacao in Peru. Its control relies primarily on synthetic insecticides, which negatively impact the environment and the health of cacao farmers. Therefore, the use of natural enemies, such as entomopathogenic fungi, represents a promising and sustainable alternative. In this study, we aimed to characterize entomopathogenic fungal isolates obtained from naturally infected A. tripterus adults in Peru. Using morphological and molecular approaches, we identified the isolates as Purpureocillium takamizusanense. Then, we assessed their pathogenic potential against A. tripterus and identified their functional cell wall groups. To evaluate pathogenicity, A. tripterus nymphs were exposed to serially diluted conidial suspensions (105–109 conidia mL−1; isolate 24M) in both laboratory and field trials. The isolates exhibited conidial viability above 99%. Concentration-mortality bioassays confirmed the lethal effect of P. takamizusanense against A. tripterus nymphs. The LC50 was 1.65 × 106 conidia mL–1, while the LT50 and LT90 were 3.08 and 7.29 days, respectively. The field mortality rate was about 52%, which can be explained by the influence of the environment. Spectroscopy analyses revealed functional groups including chitin, glucans, lipids, aliphatic chains, and proteins, which may contribute to infection and fungal persistence. This study presents the first record of P. takamizusanense in the Americas and highlights its potential as a biocontrol agent against A. tripterus in cacao plantations.

Instituciones: Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas