title: Q-RT-PCR for assessing archaea, bacteria, and fungi during leaf decomposition in a stream.
abstract: Leaf disks of Tilia cordata were exposed for up to 5 weeks in a first-order stream in Nova Scotia, Canada. The exponential decay rate k was 0.008 day(-1). Ergosterol levels increased linearly to a maximum of 134 microg g(-1) dry leaf mass. Release of conidia peaked at 700 day(-1) mg(-1) on leaves that had been exposed for 3 weeks; after 5 weeks, it declined to 15 mg(-1). In total, 23 taxa of aquatic hyphomycetes were distinguished. Anguillospora filiformis contributed over 76% of the conidia during weeks 1, 2, and 3, and 16.5% in week 5. Three sets of primers specific for Bacteria, Archaea, and Fungi were applied in quantitative real-time polymerase chain reaction (Q-RT-PCR) to estimate relative DNA amounts. Archaeal DNA was consistently present at low levels. Bacterial and fungal DNA peaked between weeks 2 and 3, and declined in week 5. With the exception of week 1, fungal DNA exceeded bacterial DNA by between 12 and 110%.
authors.affiliation: Department of Biology, Mount Allison University, Sackville, New Brunswick, E4L 1G7, Canada.
authors.forename: Mayura A
authors.initials: MA
authors.lastname: Manerkar
authors.forename: S
authors.initials: S
authors.lastname: Seena
authors.forename: Felix
authors.initials: F
authors.lastname: Bärlocher
mesh_terms: D001105:Archaea / Q000235:genetics / Q000254:growth & development*; D001419:Bacteria / Q000235:genetics / Q000254:growth & development*; D018533:Biomass; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D017753:Ecosystem; D004875:Ergosterol / Q000378:metabolism; D005658:Fungi / Q000235:genetics / Q000254:growth & development*; D018515:Plant Leaves / Q000378:metabolism / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics; D012340:RNA, Ribosomal, 5.8S / Q000737:chemistry / Q000235:genetics; D045483:Rivers
chemical_list: D019641:DNA, Archaeal; D004269:DNA, Bacterial; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S; D012340:RNA, Ribosomal, 5.8S; D004875:Ergosterol