ARS | Publication request: Using Glomalin As An Indicator for Arbuscular Mycorrhizal Hyphal Growth: An Example from a Tropical Rainforest Soil

Submitted to: Soil Biology and Biochemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 15, 2003
Publication Date: March 1, 2004
Citation: Lovelock, C.E., Wright, S.E., Nichols, K.A. 2004. Using glomalin as an indicator for arbuscular mycorrhizal hyphal growth: An example from a tropical rainforest soil. Soil Biology and Biochemistry. 36(6): 1009-1012.

Interpretive Summary: The link between a protein produced by a group of beneficial root-colonizing fungi, glomalin, and soil stability was discovered within the last decade. The fungi that produce glomalin are in a group called the arbuscular mycorrhizal fungi (AMF). AMF are very difficult to quantify in soil because the hair-like projections (hyphae) and spores they produce are microscopic in size. A study was performed to establish the relationship between glomalin and measures of hyphae because glomalin is easier to quantify than hyphae. This study was performed in the laboratory and in a tropical rain forest. The upper and lower bounds for production of hyphae in a rain forest soil were determined. This information will facilitate further studies on the role of glomalin in carbon sequestration and soil stability.

Technical Abstract: Glomalin concentrations of extra-radical arbuscular mycorrhizal (AM) hyphae were estimated by deploying hyphal in-growth cores containing glomalin-free sand in field soils in a tropical forest and in pot cultures. In field soils, glomalin was 0.044 ± 0.013 µg m-1 hyphae. In pot cultures glomalin concentrations were lower (range 0.0068 to 0.036 µg m-1), and varied among species. Using this technique, preliminary estimates of extraradical AM hyphal production were 0.24 - 2.0 Mg ha-1yr -1, or approximately 3 - 12% of estimated above ground production of the forest.