Download (PDF 2.24 MB): https://research.fs.usda.gov/download/treesearch/67938.pdf
Abstract
Oak dieback disease caused by the fungus
Paecilomyces formosus threatens oak trees in the Zagros forests in western Iran. Various insects, such as wood-infesting beetles (Coleoptera), may play a role in dissemination of
P. formosus. We collected larvae and adult insects from branch wood of oak trees with dieback symptoms in the Zagros forests. For larval identification, the mitochondrial gene cytochrome c oxidase I (COXI) was amplified by polymerase chain reaction (PCR). Fungal isolates from wood and insects collected from the sampled oaks were identified by morphology, acid production on creatine sucrose agar (CREA) medium, phylogeny of DNA sequence data for the
β-tubulin gene and the internal transcribed spacer (ITS) rDNA. To detect
P. formosus in larvae and adult insects, we used a nested PCR assay with the species-specific primer pairs PaMF and PaMR. The insects that most often tested positive for
P. formosus were larvae of the buprestids
Acmaeodera sp. and
Chrysobothris affinis, and larvae of the cerambycid
Trichoferus campestris. Adults of
C. affinis and
Calchaenesthes diversicolis (Cerambycidae), which were collected from within their galleries, also tested positive. Beetle larvae of
Anthaxia sp. (Buprestidae),
Latipalpis plana (Buprestidae),
Monochamus sp. (Cerambycidae) and
Crypticus gibbulus (Tenebrionidae) also tested positive. Larvae that tested negative for
P. formosus were species of Cossidae (Lepidoptera), Elateridae (Coleoptera), Gasteruptiidae (Hymenoptera) and Syrphidae (Diptera). Future research is needed to determine whether any of these insects can serve as vectors of
P. formosus. These results can be used to target-specific insects for monitoring.
Citation
Ghaderi, Gelareh; Jamali, Samad; Haack, Robert A.; Valipour, Jabbar. 2025. Detection of Paecilomyces formosus in wood-boring beetles associated with oak dieback and decline in the Zagros forests of Iran. Journal of Pest Science. 98(1): 413-427. https://doi.org/10.1007/s10340-024-01805-x.
