Conflicts in symbiosis: do endophytic, entomopathogenic fungi interfere with ant-seed dispersal?
A. rudis. Photo credit: Tom Murray, AntWiki.
Ant-mediated seed dispersal (myrmecochory) is a widespread phenomenon that is crucial in structuring plant communities. It is estimated that 30-40% of all understory herbs in deciduous Eastern North American forests are myrmecochores. Aphaenogaster rudis is a keystone disperser of myrmecochorous seeds in this region, and occurs in the same environments as the ubiquitous endophytic entomopathogen, Beauveria bassiana, which is capable of infecting the ants. While endophytic entomopathogens improve overall plant health and deter herbivorous arthropods, ants are capable of recognizing entomopathogenic threats. It is so far unknown if these entomopathogens negatively interfere with myrmecochorous dispersal systems.
Using laboratory cafeteria experiments with A. rudis and seeds of the myrmecochore, Asarum canadense, we show that entomopathogenic presence has the potential to interfere with the myrmecochory mutualism by decreasing seed-dispersal by ants; thus creating conflicts in symbioses.
Using laboratory cafeteria experiments with A. rudis and seeds of the myrmecochore, Asarum canadense, we show that entomopathogenic presence has the potential to interfere with the myrmecochory mutualism by decreasing seed-dispersal by ants; thus creating conflicts in symbioses.
Bringing a historic collection into the modern era: curating the J. K. Underwood seed collection at the University of Tennessee (TENN)
Seed collections housed at herbaria constitute unique sources of biological information that are distinct from pressed vegetative specimens. The herbarium at the University of Tennessee - Knoxville (TENN) is the third largest herbarium in the southeast and contains over 600,000 dried plant specimens. Recently, curators at TENN rediscovered a historic and poorly-curated seed collection hidden away in storage: the J. K. Underwood Seed Collection.
In 2017, a curation project was undertaken to modernize the collection and render it useful to researchers as a reference collection for seed identification and as a repository of seed morphological data. This included curating specimens from their original vials into boxes containing modern herbaria labels that were more accessible and more protective of the seeds. We alphabetized the collection by species name and housed it in temperature-controlled shelving. We are also in the process of photographing seeds and adding images to the TENN website, and hope to advertise the utility of the collection as an identity reference for researchers, a teaching tool, and a source of physical data on seeds in the form of measurements and appearance.
In 2017, a curation project was undertaken to modernize the collection and render it useful to researchers as a reference collection for seed identification and as a repository of seed morphological data. This included curating specimens from their original vials into boxes containing modern herbaria labels that were more accessible and more protective of the seeds. We alphabetized the collection by species name and housed it in temperature-controlled shelving. We are also in the process of photographing seeds and adding images to the TENN website, and hope to advertise the utility of the collection as an identity reference for researchers, a teaching tool, and a source of physical data on seeds in the form of measurements and appearance.
Original glass vials housing the collection
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Photograph of Amaranthus albus ​from the collection. 2018.
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