Molecular characterisation of native entomopathogenic fungi from ambrosia beetles in hazelnut orchards of Turkey and evaluation of their in vitro efficacy

Turkey is the world's largest hazelnut producer and exporter country. Ambrosia beetle species are the most common species of pests of hazelnut in orchards of Turkey. These beetles cause enormous economic losses by draining hazelnut branches and trees. The techniques in managing ambrosia beetles are used to a limited extent. The more effective and eco-friendly alternative control methods, including the use of entomopathogenic fungi (EPF), should be included in integrated pest management to suppress ambrosia beetle populations. The objectives of the current study were to i) isolate EPF from ambrosia beetles individuals obtained from Turkey's main hazelnut production areas; ii) characterise EPF isolates using DNA sequencing and iPBS profilings; and iii) assess the effectiveness of isolates against three ambrosia beetle species under laboratory conditions. A total of 47 EPF isolates were obtained from cadavers and classified into 8 EPF species. The Primer Binding Site (PBS) marker system was used to discriminate the EPF species successfully for the first time. Some isolates caused 100% mortality of the beetle species within 7-9 days, depending on the applied beetle species, demonstrating their effectiveness in managing pests. Major EPF species in this study provided an important basis for developing bioproducts and a possible alternative control approach against these ambrosia beetles.