Abstract
Invasions by non-native pathogens represent a major threat to managed and natural ecosystems worldwide. Although necessary for adopting preventive strategies, the identification of invasive species before they are introduced is particularly difficult. Indeed, most pathogenic species that have become established in the last decades were first described only after they became invasive. To prevent further biological invasions, not only the early identification of potential new invasive plant pathogens is crucial, but also the assessment of their potential host range. In this study, we determined the pathogenicity and the saprotrophic ability of three Cryphonectria species towards three potential hosts in the family Fagaceae. For this, seedlings and dormant stems of European chestnut (Castanea sativa), pedunculate oak (Quercus robur) and European beech (Fagus sylvatica) were inoculated with different genotypes of C. parasitica (Asian species, invasive in Europe), C. naterciae (European species), and C. japonica (Asian species, not present in Europe). Lesion growth was measured and mortality assessed for four months. The highest damage was caused by C. parasitica on European chestnut, while C. japonica and C. naterciae induced significantly smaller lesions on this host species. All three Cryphonectria species did not grow saprophytically on F. sylvatica and Q. robur, but successfully colonized dormant stems of C. sativa. In the context of biological invasions, our study shows that the Asian C. japonica most likely represents a much less severe threat than C. parasitica for the tested European host species. Nonetheless, the ability of C. naterciae and C. japonica to saprotrophically colonize fresh chestnut wood may suggest that they could become established in chestnut forests and eventually infect weakened chestnut trees or other hosts not tested in this study.
Highlights
The risk of accidentally moving plant pathogens outside their native range is constantly increasing because of global trade and other anthropogenic activities (Santini et al, 2013)
We aimed to compare the parasitic and saprotrophic ability of the Asian C. japonica with that of an invasive species already established in Europe (C. parasitica) and a native European species (C. naterciae)
Mortality was only observed on chestnut seedlings inoculated with C. parasitica
Summary
The risk of accidentally moving plant pathogens outside their native range is constantly increasing because of global trade and other anthropogenic activities (Santini et al, 2013). Climatic changes, which allow pests to survive in formerly climatic adverse regions, further contribute to range expansions (Stenlid and Oliva, 2016). Harmful organisms frequently encounter new plant species, some of which may be highly susceptible. In this case, the introduced pest can become invasive (Ghelardini et al, 2017). Detecting invasive species before they are introduced is difficult. Most pathogenic species that have become established in the last decades were first described only after they became invasive (Brasier, 2008). Assessing the pathogenicity of related species of already present invasive pathogens may be a valuable strategy to spot potentially invasive species before they are introduced (Gilbert et al, 2015)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
