Detecting Pathogenic Species Using Volatile Organic Compounds.

There are several highly damaging species pathogenic to forest trees, many of which have been spread beyond their native range by the international trade of live plants and infested materials. Such introductions can be reduced through the development of better tools capable of the early, rapid, and high-throughput detection of contaminated plants. This study utilized a volatilomics approach (solid-phase microextraction coupled to gas chromatography-mass spectrometry) to differentiate between several species in culture and discriminate between healthy and -inoculated European beech and pedunculate oak trees. We tentatively identified 14 compounds that could differentiate eight species from each other in vitro. All of the species examined, except , uniquely produced at least one compound not observed in the other species; however, most detected compounds were shared between multiple species. had the most unique compounds and was the least similar of all the species examined. The inoculated seedlings had qualitatively different volatile profiles and could be distinguished from the healthy controls by the presence of isokaurene, anisole, and a mix of three unknown compounds. This study supports the notion that volatiles are suitable for screening plant material, detecting tree pathogens, and differentiating between healthy and diseased material.