Submerged aquatic vegetation (SAV) is an essential component of freshwater spring ecosystems, where it stabilizes soil, facilitates nutrient uptake and cycling, sequesters carbon, and provides habitats for a diversity of fishes and invertebrates. The SAV in Florida’s freshwater springs, part of one the largest aquifers in the United States, are incredibly diverse and help sustain a unique freshwater food web. Unfortunately, SAV populations in Florida’s springs are currently in decline due to both environmental and anthropogenic stressors. One aspect of SAV health that has not been thoroughly investigated is the potential role of viral infection in SAV decline and how viral-SAV interactions may change with increasing anthropogenic stressors. The main objective of this study is to identify viruses associated with SAV in Florida’s springs using viral purification, Sequence Independent Single Primer Amplification (SISPA), and sequencing. Up to 8 SAV species were collected in July 2017 from each of four Florida springs (Ichetucknee, Rainbow, Manatee and Blue Springs). Upon collection, epiphytes were removed immediately from the SAV and virus particles were purified from plant material through bead-beating, filtration, and nuclease treatment. Viral nucleic acids were then extracted from each sample, processed with SISPA, sequenced, and compared to known viral sequences.
Results/Conclusions
Viral sequences were identified in SAV from Ichetucknee, Manatee, and Blue Springs. These sequences were most similar to viruses infecting invertebrates, diatoms, algae, and terrestrial plants. However, most of the sequences had low similarities (< 70% amino acid identity) to known viruses, indicating that SAV harbor a diversity of novel viruses. We have determined the host range and distribution of each virus by screening various species of SAV from different springs through PCR. Current efforts focus on completing the genomes of these novel viruses, with an emphasis on potential plant-infecting viruses. Future work will examine the epidemiology and transmission dynamics of these viruses and determine their effects on the ecology of SAV, providing valuable information for the conservation of aquatic plants in these threatened ecosystems.