Eco-Friendly Biocontrol Of Citrus Aphids Using Entomopathogenic Fungi In Algerian Citrus Orchards

Abstract

Citrus cultivation constitutes a cornerstone of socio-economic development in the Chlef region of Algeria, supporting both agricultural productivity and rural livelihoods. However, the widespread presence of pesticide residues across environmental compartments has become a pressing global concern, raising critical questions about the long-term sustainability of conventional pest management practices. In response, this study explores   the entomophagous potential of selected fungal microorganisms against citrus aphids. Specifically, the pathogenicity of three entomopathogenic fungi Metarhizium anisopliae, Cordyceps militaris, and Fusarium sp. was assessed in vitro against the green citrus aphid (Aphis spiraecola Patch, 1914). Bioassays were conducted in Petri dishes containing citrus leaves treated with fungal suspensions at a concentration of 10⁶ spores/ mL. Insect mortality was recorded at two-hour intervals. The results revealed LT₅₀ values of 8 hours (larvae) and 27 hours (adults) for M. anisopliae, 17 hours for C. militaris, and 29 hours (larvae) and 35 hours (adults) for Fusarium sp. All fungal isolates induced up to 100% mortality within 36 hours of application.These findings highlight the strong biocontrol potential of the tested fungi against A. spiraecola and support their integration into pest management strategies to reduce chemical pesticide use in citrus orchards both in the Algeria and throughout Mediterranean region.