Fungal endophytes from seeds of invasive, non-native Phragmites australis and their potential role in germination and seedling growth
- 1.3k Downloads
Background and aims
We characterized fungal endophytes of seeds of invasive, non-native Phragmites from three sites in the Great Lakes region to determine if fungal symbiosis could contribute to invasiveness through their effects on seed germination and seedling growth.
Field-collected seeds were surface sterilized and plated on agar to culture endophytes for ITS sequencing. Prevalence of specific endophytes from germinated and non-germinated seeds, and from seedlings, was compared.
One-third of 740 seeds yielded endophyte isolates. Fifteen taxa were identified with Alternaria sp. representing 54% of all isolates followed by Phoma sp. (21%) and Penicillium corylophilum (12%). Overall germination of seeds producing an isolate (36%) was significantly higher than seeds not producing an isolate (20%). Penicillium in particular was strongly associated with increased germination of seeds from one site. Sixty-three isolates and 11 taxa were also obtained from 30 seedlings where Phoma, Penicillium and Alternaria respectively were most prevalent. There was a significant effect of isolating an endophyte from the seed on seedling growth.
These results suggest that many endophyte taxa are transmitted in seeds and can increase seed germination and seedling growth of invasive Phragmites. The role of fungal endophytes in host establishment, growth and invasiveness in nature requires further research.
KeywordsPhragmites australis Seed endophytes Biological invasion Germination Seedling growth Fungi
This research was funded by the USGS cooperative agreement G13 AC00285 to Indiana University. Any use of trade, firm or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. We thank the Clay Lab group at Indiana University, Ray Callaway (University of Montana), and two anonymous reviewers for their useful comments on a previous version of this manuscript.
- Keller BEM (2000) Plant diversity in Lyrthrum, Phragmites, and Typha marshes, Massassachussets, U.S.A. wetlands. Ecol Manag 8:391–401Google Scholar
- Kirk H, Paul J, Straka J, Freeland JR (2011) Long-distance dispersal and high genetic diversity are implicated in the invasive spread of the common reed, Phragmites australis (Poaceae), in northeastern North America. Amer J Bot 98:1180–1190Google Scholar
- Kowalski KP, Bacon C, Bickford W, Braun H, Clay K, Leduc-Lapierre M, Lillard E, McCormick M, Nelson E, Torres M, White J, Wilcox DA (2015) Advancing the science of microbial symbiosis to support invasive species management: a case study on Phragmites in the Great Lakes. Front Microbiol 6:95CrossRefPubMedPubMedCentralGoogle Scholar
- Saltonstall K, Burdick D, Miller S, Smith B (2005) Native and non-native Phragmites: challenges in identification, research, and management of the common reed. National Estuarine Research Reserve Technical Report Series 2005Google Scholar
- Schardl CL, Clay K (1997) Evolution of mutualistic endophytes from plant pathogens. Plant Relationships Part B:221–238Google Scholar
- Scheffer RP (1997) The nature of disease in plants. Cambridge University Press, CambridgeGoogle Scholar
- White TJ, Bruns T, Lee SJ, Taylor JW (1990) Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. PCR protocols: a guide to methods and applications 18:315–322Google Scholar