TY - JOUR
T1 - Using quantitative PCR to determine the distribution of a semicryptic benthic diatom, Navicula phyllepta (Bacillariophyceae)
AU - Creach, V.
AU - Ernst, A.
AU - Sabbe, K.
AU - Stal, L.J.
AU - Vanelslander, B.
AU - Vyverman, W.
N1 - Reporting year: 2006
Metis note: 3849;CEME; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs2006/Creach_ea_3849.pdf
PY - 2006
Y1 - 2006
N2 - Evidence has accumulated during the last decade showing that many established diatom morpho-species actually consist of several semicryptic or truly cryptic species. As these species are difficult or even impossible to differentiate by microscopic analysis, there is virtually no information on how they behave in natural environments. In this study, we developed a quantitative real-time PCR (qPCR) assay using TaqMan probes® targeted to the internal transcribed spacer 1 (ITS1) to assess the spatial distribution and seasonal dynamics of an important component of the microphytobenthos of intertidal sediments. Navicula phyllepta Kützing is a brackish-marine morpho-species with a cosmopolitan distribution. Axenic clones of this species were isolated from natural assemblages of benthic diatoms at different intertidal stations in the Westerschelde estuary (The Netherlands). At least two distinct semicryptic species of N. phyllepta were present, as shown by differences in the quantity of DNA per cell, the ITS1 sequences and the copy number of ITS per cell. DNA and chl a concentrations extracted from sediment surface samples were closely correlated, showing that the DNA used for subsequent analysis mostly belonged to the microalgal community. The results of real-time qPCR from sites throughout the estuary and over several seasons agreed well with microscopic counts. Additionally, the seasonal pattern of the two forms of N. phyllepta showed an overlapping, but unique distribution along the estuary. [KEYWORDS: diatoms ; estuary ; Navicula phyllepta ; niche differentiation ; real-time qPCR ; semicryptic species]
AB - Evidence has accumulated during the last decade showing that many established diatom morpho-species actually consist of several semicryptic or truly cryptic species. As these species are difficult or even impossible to differentiate by microscopic analysis, there is virtually no information on how they behave in natural environments. In this study, we developed a quantitative real-time PCR (qPCR) assay using TaqMan probes® targeted to the internal transcribed spacer 1 (ITS1) to assess the spatial distribution and seasonal dynamics of an important component of the microphytobenthos of intertidal sediments. Navicula phyllepta Kützing is a brackish-marine morpho-species with a cosmopolitan distribution. Axenic clones of this species were isolated from natural assemblages of benthic diatoms at different intertidal stations in the Westerschelde estuary (The Netherlands). At least two distinct semicryptic species of N. phyllepta were present, as shown by differences in the quantity of DNA per cell, the ITS1 sequences and the copy number of ITS per cell. DNA and chl a concentrations extracted from sediment surface samples were closely correlated, showing that the DNA used for subsequent analysis mostly belonged to the microalgal community. The results of real-time qPCR from sites throughout the estuary and over several seasons agreed well with microscopic counts. Additionally, the seasonal pattern of the two forms of N. phyllepta showed an overlapping, but unique distribution along the estuary. [KEYWORDS: diatoms ; estuary ; Navicula phyllepta ; niche differentiation ; real-time qPCR ; semicryptic species]
U2 - 10.1111/j.1529-8817.2006.00268.x
DO - 10.1111/j.1529-8817.2006.00268.x
M3 - Article
SN - 0022-3646
VL - 42
SP - 1142
EP - 1154
JO - Journal of Phycology
JF - Journal of Phycology
IS - 5
ER -