Abstract

Biological control studies have been increasingly performed against agricultural and forest pests. To develop a biological control agent, bacteria was isolated from harmful pests and identified using various tests. Xylosandrus germanus (Blandford, 1894) (Coleoptera: Curculionidae) is a harmful pest in the hazelnut orchards and other fruit-tree cultures. In this study, we identified 16 bacteria isolates from healthy X. germanus collected in hazelnut orchards in Turkey. Isolates were characterized based on morphological, physiological and biochemical properties using the VITEK 2 Identification System and the fatty acid methyl esters (FAME) analysis. In addition, 16S rRNA gene sequencing of bacterial isolates was performed. Associated bacteria were identified as Acinetobacter psychrotolerans (2 strains), Stenotrophomonas maltophilia, Pseudomonas fluorescens (two strains), Staphylococcus sciuri, Staphylococcus warneri, Pantoea agglomerans (two strains), Staphylococcus hominis subsp. hominis, Erwinia billingiae (two strains), Brevibacterium linens, Advenella sp., Pantoea cedenensis and Brevibacterium permense. Several species of these bacteria are used in biological control as an antifungal and insecticidal against agricultural pest. In the future, their biological control properties will be investigated. This is the first study on the bacterial community of X. germanus.

Key words: Xylosandrus germanus, hazelnut, 16S rRNA, fatty acid methyl esters (FAME), VITEK 2, bacterial symbionts, mutualism, biological control.