| Title: | Symbiotic Fungi of an Ambrosia Beetle Alter the Volatile Bouquet of Cork Oak Seedlings |
| Author(s): | Nones S; Sousa E; Holighaus G; |
| Address: | "Agrarian and Forestry Systems and Vegetal Health Unit, National Institute for Agricultural and Veterinary Research (INIAV, I.P.), Av. da Republica, Quinta do Marques, 2780-159 Oeiras, Portugal. GREEN-IT Bioresources for Sustainability, ITQB NOVA, Av. da Republica, 2780-157 Oeiras, Portugal. Institute of Chemical and Biological Technology Antonio Xavier, NOVA University of Lisbon, Av. da Republica, 2780-157 Oeiras, Portugal. Department of Forest Zoology and Forest Conservation, Busgen Institute, Georg-August-University Gottingen, Busgenweg 3, 37077 Gottingen, Germany. Northwest German Forest Research Institute, Department of Forest Protection, Gratzelstrasse 2, 37079 Gottingen, Germany" |
| DOI: | 10.1094/PHYTO-08-21-0345-R |
| ISSN/ISBN: | 0031-949X (Print) 0031-949X (Linking) |
| Abstract: | "In Portugal, fungal symbionts of the ambrosia beetle Platypus cylindrus affect tree vigor of cork oak (Quercus suber) and are linked with the cork oak decline process. Fungal symbionts play crucial roles in the life history of bark and ambrosia beetles and recent work indicates complex interactions on the fungal and plant metabolic level. Colonized trees may respond with an array of currently unknown volatile metabolites being indicative of such interactions, acting as infochemicals with their environment. In this study, we examined volatile organic compounds (VOCs) of cork oak seedlings wound inoculated with strains of three fungal associates of P. cylindrus (Raffaelea montetyi, R. quercina, and Ceratocystiopsis sp. nov.) over a 45-day period by means of thermodesorption gas chromatography-mass spectrometry techniques. Fungal strains induced largely quantitative but species-specific changes among the 58 VOCs characterized. Overall, monoterpenes-the major volatiles of cork oak foliage-were significantly reduced, possibly a result of fungal biotransformation. Acetophenone, sulcatone, and nonanal-volatiles known for mediating ambrosia beetle behavior-increased in response to fungal inoculation. Qualitative VOC profiles of excised tissue of wood lesions (21 VOCs) and pure fungal cultures (60 VOCs) showed little overlap with seedling VOCs, indicating their plant-derived but fungal-induced origin. This chemoecological study expands on the limited knowledge of VOCs as infochemicals emitted from oak trees threatened by oak decline in relation to beetle-vectored ophiostomatoid fungi. It opens new avenues of research to clarify mutualistic or pathogenic aspects of these complex symbiotic interactions and develop new control strategies for P. cylindrus, including its mycobiota" |
| Keywords: | Ambrosia Animals *Coleoptera/microbiology Fungi/physiology Plant Diseases/microbiology *Quercus/microbiology Seedlings Trees *Volatile Organic Compounds/pharmacology *Weevils/microbiology Ceratocystiopsis sp.Platypus cylindrus Quercus suber Raffaelea spp; |
| Notes: | "MedlineNones, Stefano Sousa, Edmundo Holighaus, Gerrit eng 2022/04/01 Phytopathology. 2022 Sep; 112(9):1965-1978. doi: 10.1094/PHYTO-08-21-0345-R. Epub 2022 Aug 2" |
