Soil fungal community structure in a temperate upland grassland soil

Abstract

Alterations in soil microfungal community structure across a transect between a semi-natural upland grassland and an agriculturally improved enclosure were assessed using an indirect measurement of active fungal biomass (ergosterol), together with a nucleic acid approach, terminal restriction fragment length polymorphism (TRFLP), which was compared to a commonly used but less sensitive community fingerprinting technique, denaturing gradient gel electrophoresis (DGGE). These techniques indicated that there was no reduction in numbers of fungal ribotypes across the floristic transect, despite decreased floristic diversity and a reduction of more than two-fold in ergosterol concentration. Although there were no differences in ribotype number, there was a decrease in diversity and an increase in dominance in only one of the transitional areas. The highest degree of variability within fungal communities was also found in this transitional area, with 84% of ribotypes only being detected in one of three replicates. Comparison of the two fungal community fingerprinting approaches indicated that TRFLP (26-33 ribotypes) was more sensitive for monitoring alterations in fungal community structure than DGGE (13-18 ribotypes). Using a measurement of the relative percentage of each ribotype within communities, a decrease in abundance of prominent ribotypes of the natural grassland soil fungal community was indicated together with an emergence of previously undetected ribotypes towards the improved area. This may have important implications for ecosystem stability or productivity, particularly if agricultural inputs to managed grasslands are suspended.

Molecular characterization of the spatial diversity and novel lineages of mycoplankton in Hawaiian coastal waters

“…Application of PCR in amplifying 18S rRNA genes has contributed to our better understanding of evolutionary relationship between fungi (White et al, 1990;Wilmotte et al, 1993) and also enhanced our ability to describe fungal communities with respect to environmental factors and perturbations (Kowalchuk et al, 1997;Malosso et al, 2006;Oros-Sichler et al, 2006;Jumpponen, 2007). DGGE analysis based on 18S rRNA fragments has been used to reveal fungal communities in many terrestrial natural habitats (Kowalchuk et al, 1997;Borneman and Hartin, 2000;Vainio and Hantula, 2000;May et al, 2001;Brodie et al, 2003;Nikolcheva et al, 2003), but its application for investigating fungal communities in marine environments remains rare (Pang and Mitchell, 2005;Gao et al, 2008). This report describes the first use of a DGGE-based strategy targeting this gene to characterize planktonic fungal communities in the Hawaiian coastal waters.…”

Patterns of fungal diversity and composition along a salinity gradient

“…In particular, fungal abundance often increases with plant diversity (Kowalchuk et al, 2002;Zak et al, 2003;van der Heijden et al, 2008). Greater plant diversity may also increase fungal diversity by increasing microclimate variability, habitat complexity and organic substrate diversity, but experiments that seek to link plant diversity with fungal diversity report inconsistent findings (Kowalchuk et al, 2002;Brodie et al, 2003;Waldrop et al, 2006;Artz et al, 2007).…”

Species-specific effects of polyploidisation and plant traits of Centaurea maculosa and Senecio inaequidens on rhizosphere microorganisms

“…where C = 2.3, N = sum of peak heights, n i = height of TRF i, and i = number of TRFs in each T-RFLP profile (Brodie et al 2003).…”