Diversity of Entomopathogenic Fungi in Hazelnut Plantations in the Black Sea Region of Georgia

Abstract

The commercial production of hazelnuts requires the control of its pests. Entomopathogenic fungi are a potential option for the suppression of their numbers and the reduction of the human health and environmental impacts of synthetic pesticide use. The aim of our research was to isolate entomopathogenic fungi from hazelnut plantations in the Black Sea Region of Georgia and to identify the species. Plantations in the Guria, Samegrelo and Adjara regions of West Georgia were selected for the study. Species of entomopathogenic fungi were identified by their morphology and by sequencing of the rDNA region with ITS4 and ITS5 primers and a mitochondrial nad1 gene fragment. BLASTN analysis of the sequenced isolates showed that the isolates had between 95% and 100% similarity to the isolates of entomopathogenic fungi in the database. The identified fungi were Beauveria bassiana, Hirsutella thompsonii, Lecanicillium lecanii, Metarhizium brunneum, Metar-hizium sp. and Purpureocillium lilacinum. Hirsutella thompsonii and L. lecanii were isolated from the hazelnut big bud mite, Phytoptus avellanae, and B. bassiana, M. brunneum, Metarhizium sp. and P. lilacinum were isolated from different soil samples. Specifically, M. brunneum and P. lilacinum were isolated from fluvisols of Samegrelo and from nitisols in Adjara, respectively, and B. bassiana was isolated from cambisols in Guria. © 2022 Bull. Georg. Natl. Acad. Sci.