Research project Frass-based identification of quarantine wood boring beetles
General introduction
Wood-boring beetles, the most important tree pests, cause considerable economic damage to forests worldwide. The damage remains undetected for some time as it occurs during the phase when the beetle larvae live in the trunk. In the QFRASS project, existing molecular identification methods were refined for three wood-boring beetles. These methods are based on frass - the bore dust (wood particles) and excrement of the beetle larvae (which are themselves inaccessible for sampling in the tree bark). The project focused specifically on three quarantine pests: Aromia bungii, Agrilus planipennis and Pityophthorus juglandis. The frass of these beetles has proven to be successful for species recognition, not through morphology (which is too variable for reliable identification), but through the molecular protocols validated here.
Research approach
The researchers collected more than 140 frass samples in Belgium, supplemented with material from the three quarantine pests via international partners. Various DNA extraction methods were tested on the samples, with the innuPREP TCM DNA Extraction Kit yielding the most consistent results. For each target species, both qPCR and LAMP tests were validated, with particular attention to DNA quality, necessary dilution steps and the influence of the composition of the frass. Based on these results, a practical and ready-to-use molecular identification protocol was developed for each species. An illustrated guide has also been developed for morphological identification at the family level, allowing samples to be selectively forwarded for more detailed molecular analysis via qPCR or LAMP. These protocols are now complete for each species.
Relevance/Valorization
The molecular protocols, which enable rapid, specific and sensitive detection of quarantine beetles based on frass, can support national reference laboratories in monitoring the three quarantine beetles – Aromia bungii, Agrilus planipennis and Pityophthorus juglandis – and in border controls. The researchers also recommended standardizing DNA extraction from frass across European laboratories and further broadening the specificity tests for A. bungii and P. juglandis. This will enable these pests to be detected more quickly, efficiently and reliably, which will significantly increase the chances of survival for the affected trees.
Financing
FOD Volksgezondheid, Veiligheid van de voedselketen en Leefmilieu
