Enzymatic Secretion, Bioassay, and Morphogenetic Identification of Entomopathogenic Fungus, Albifimbria terrestris Associated with Mosquitoes

Abdel-Galil1, Farouk A.; Morsy, Sina M.; Farghal, Ahmed I. A.; Abdel-Nasser, Mohamed A.; Moharram, Ahmed M.; Al-Bedak, Osama A. M.; Aboulnasr, Gehad N.; Mousa, Sara E.

doi:10.21608/eajbsg.2025.430203

Enzymatic Secretion, Bioassay, and Morphogenetic Identification of Entomopathogenic Fungus, Albifimbria terrestris Associated with Mosquitoes

Document Type : Original Article

Authors

¹ Department of Plant Protection, Faculty of Agriculture, Assiut University, Assiut 71511, Egypt.

² Department of Botany and Microbiology, Faculty of Science, Assiut University, Assiut, Egypt.

³ Assiut University Mycological Centre, Assiut University, Assiut 71511, Egypt.

⁴ Zoology Department, Faculty of Science, Assiut University, Assiut, Egypt.

10.21608/eajbsg.2025.430203

Abstract

The worldwide prevalence of Culex pipiens (Diptera: Culicidae), a mosquito known for its disease-transmitting capabilities and nuisance biting, is a serious concern. Given the growing ineffectiveness of chemical insecticides due to insect resistance, sustainable and ecologically friendly control strategies are urgently required. Safe strains of entomopathogenic fungi presents a workable solution for managing the larvae of this mosquito. Results indicated that Albifimbria terrestris AUMC 16014 (Stachybotriaceae) was recorded, for the first time in Egypt, from agriculture drainage water in Assiut Governorate (Identified based on morphological and molecular rules and sequenced in GenBank under accession number OR039364). The ability of A. terrestris strain to synthesize extracellular chitinase, lipase, protease, and phospholipase was evaluated. The maximal activity of chitinase, lipase, and protease was found to be 4.053 U/mL/min, 10.63 U/mL/min and 458.16 U/mL/min, respectively, at pH 6.0. A second possible product of A. terrestris is the phospholipase enzyme. Cx. pipiens 2^nd instar larvae were exposed to three concentrations of A. terrestris strain spores (1×10⁶, 1×10⁷, and 1×10⁸ spore/mL). LT₉₀ values of the three concentrations were, in order, 5.95, 5.57, and 5.09 days, respectively. While the corresponding LT₅₀ values were 3.12, 2.71, and 2.34 days, respectively. The efficiency of the fungus increased with increasing concentration. So, the isolated fungus associated with mosquitoes in the present study can play an active role as a biocontrol agent in the Integrated pest management approach. It can be considered promising in the future with further investigations. This contributes to achieving the Sustainable Development Goals (SDGs).

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