Using lipid analysis and hyphal length to quantify AM and saprotrophic fungal abundance along a soil chronosequence

doi:10.1016/j.soilbio.2004.08.019

Soil Biology and Biochemistry

Volume 37, Issue 3, March 2005, Pages 601-604

https://doi.org/10.1016/j.soilbio.2004.08.019 Get rights and content

Abstract

We evaluate the use of signature fatty acids and direct hyphal counts as tools to detect and quantify arbuscular mycorrhizal (AM) and saprotrophic fungal (SF) biomass in three Hawaiian soils along a natural soil fertility gradient. Phospholipids16:1ω5c and 18:2ω6,9c were used as an index of AM and saprotrophic fungal biomass, respectively. Both phospholipid analysis and hyphal length indicated that the biomass of AMF was greatest at the highest fertility site, and lowest where phosphorus limits plant growth. Saprotrophic fungal biomass did not vary. Hyphal length counts appeared to under-estimate SF abundance, while the phospholipid AMF:SF ratio was in line with expectations. This study indicates that phospholipids may be a valuable and reliable tool for studying the abundance, distribution, and interactions between AM and saprotrophic fungi in soil.

Section snippets

Conclusions

While microscopic measurement of hyphal length has been the most widely used method for estimating AM biomass in soil, the method does not allow systematic or functional separation of different (e.g. AMF versus SF) fungal mycelia, nor reliable separation of the dead and live fraction of fungal biomass (Sylvia, 1992, Olsson, 1999). In contrast, lipid biomarkers allow for sensitive and simultaneous estimation of live AMF and SF biomass. Overall, we found that phospholipids 16:1ω5c and 18:2ω6,9c

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Short communicationUsing lipid analysis and hyphal length to quantify AM and saprotrophic fungal abundance along a soil chronosequence

Abstract

Section snippets

Conclusions

Comparison of soil fungal/bacterial ratios in a pH gradient using physiological and PLFA-based techniques

Soil Biology & Biochemistry

The impact of long-term nitrogen addition on microbial community composition in three Hawaiian forest soils

The Scientific World

Comparison of two methods for quantifying extraradical mycelium of vesicular-arbuscular mycorrhizal fungi

Soil Science Society of American Journal

A rapid method of total lipid extraction and purification

Canadian Journal of Biochemical Physiology

Anatomy and morphology of VA mycorrhizae

Changes in soil phosphorus fractions and ecosystem dynamics across a long chronosequence in Hawaii

Ecology

The use of phospholipid fatty acid analysis to estimate bacterial and fungal biomass in soil

Biology and Fertility of Soils

Phosphorus limitation of forest leaf area and net primary production on a highly weathered soil

Biogeochemistry

Comparison of the lipid profiles of arbuscular mycorrhizal (AM) fungi and soil saprophytic fungi

Symbiosis

Vegetation changes along gradients of long-term soil development in the Hawaiian montane rainforest zone

Vegetation

Estimation of conversion factors for fungal biomass determination in compost using ergosterol and PLFA 18:2w6,9

Soil Biology & Biochemistry

The use of fatty acid signatures to study mycelial interactions between the arbuscular mycorrhizal fungus Glomus intraradices and saprotrophic fungus Fusarium culmorum in root-free soil

Mycological Research

Combining sterol and fatty acid profiles for the characterization of fungi

Mycological Research

Short communication
Using lipid analysis and hyphal length to quantify AM and saprotrophic fungal abundance along a soil chronosequence