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Fragmented environment affects birch leaf endophytes
M Helander1, J Ahlholm2, T N Sieber3
1Section of Ecology, Department of Biology, University of Turku, FIN-20014 Turku, Finland, and MTT Agrifood Research Finland, Plant Production, FIN-31600 Jokioinen, Finland.
The New Phytologist
|July 20, 2007
Summary
Environmental fragmentation impacts endophytic fungi in birch leaves. Island size and distance from the mainland significantly influence fungal frequencies, with larger, closer islands supporting higher frequencies.
Area of Science:
- Ecology
- Mycology
- Botany
Background:
- Horizontally transmitted endophytic fungi inhabit plant tissues.
- Environmental fragmentation can alter species distribution and fungal frequencies.
- Birch trees (Betula pubescens and Betula pendula) host various endophytic fungi.
Purpose of the Study:
- To investigate the effect of environmental fragmentation on endophytic fungal communities in birch leaves.
- To determine the relationship between island size, distance to mainland, and fungal frequencies.
- To identify common endophytic fungal species in the studied birch populations.
Main Methods:
- Studied 14 islands and 5 mainland sites in an archipelago in southwestern Finland.
- Isolated endophytic fungi from surface-sterilized leaves of Betula pubescens and Betula pendula.
- Analyzed the influence of island size and distance to mainland on fungal frequency.
Main Results:
- Island size explained 32-35% of the variation in endophytic fungal frequency.
- Distance to the mainland explained 29-35% of the variation in fungal frequency.
- Highest endophyte frequencies were observed on the largest islands closest to the mainland.
Conclusions:
- Foliar endophytes of birch trees can disperse across fragmented landscapes.
- Environmental isolation and island size are key factors determining endophytic fungal frequencies.
- Fusicladium betulae, Gnomonia setacea, and Melanconium betulinum were the most prevalent endophytic fungi.
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