Abstract:
Sri Lanka is a biodiversity hotspot and a significant contributor to global
biodiversity. It is estimated that Sri Lanka is home to approximately 34,000
fungal species, with only around c. 3,000 of them currently documented, leaving
approximately 31,000 undescribed. Notably, the documentation of fungal
diversity in Sri Lanka's freshwater ecosystems has been inadequate. The main
objective of this study was to reveal the hidden fungal diversity in freshwater
ecosystems in Anuradhapura and Ratnapura districts. Accordingly, fungal
samples from submerged dead plant specimens and live aquatic plants were
collected in fifteen and ten freshwater habitats (lentic and lotic) in Anuradhapura
and Ratnapura districts, respectively. Fungal isolation was conducted using single
spore isolation and direct isolation techniques. Approximately 120 living fungal
cultures were maintained in the culture collection of Rajarata University of Sri
Lanka on PDA media and sterilized distilled water at -4 °C. Identification was
carried out based on morphological characteristics such as macro morphology,
micromorphology, and colony characteristics as well as molecular
characterization. Preliminary molecular identification was conducted by using
ITS (primers: ITS1F/ITS4) loci to identify the nine fungal genera including,
Aureobasidium,
Coniochaeta,
Hypoxylon,
Lentinus,
Lasiodiplodia,
Neopestalotiopsis, Neurospora, Rhytidhysteron, and Trichoderma. Moreover,
LSU (primers: LROR/LR5), SSU (primers: NS1/NS4), and RPB2 (primers:
fRPB2-5F/fRPB2-7Cr) loci will be utilized to confirm the further accuracy of the
identification. Consequently, this study will contribute to the identification of
existing fungal genera, their species diversity, novel fungal taxa, and ingoldian
fungi (or freshwater fungi sensu stricto) within the hidden fungal diversity of
freshwater ecosystems in Sri Lanka.
