Abstract Detail

Molecular Ecology and Evolution

Carter, Keith [1], Serpe, Marcelo [1], Smith, James [1].

Assessing the Diversity of Mycorrhizal Communities in Sagebrush Steppes of Southwestern Idaho.

Arbuscular mycorrhizal fungi (AMF) are obligate biotrophs that play important roles in the functioning of natural ecosystems. Presently, little is known about AMF native to sagebrush habitats. The major goal of the present study was to gain information in this area and in particular to identify AMF that colonize seedlings of A. tridentata subsp. wyomingensis. For this purpose, we collected A. tridentata seedlings and soil samples from seven sagebrush communities in southwestern Idaho. Additionally, AMF present in the soil were multiplied in pot cultures. Mycorrhizae were identified using molecular methods following DNA extraction from field and pot culture samples. The extracted DNA was amplified using Glomeromycota specific primers and identification of AMF was based on sequences from the large subunit-D2 rDNA region. The phylogenetic analyses revealed seven phylotypes, two within the Claroideoglomeracea and five within the Glomeraceae. Four phylotypes clustered with known species including Claroideoglomus claroideum, Rhizophagus irregularis, Glomus microaggregatum, and Funneliformis mosseae. The other three phylotypes had similarity with several published sequences, but all of these were from uncultured and unnamed glomeromycetes. As measured by pairwise distance analysis, some phylotypes showed high genetic variation. The most diverse was the phylotype that included R. irregularis. This phylotype included sequences showing pairwise differences up to 12% and could be subdivided into five groups with pairwise differences larger than 6%. Comparison of sequences obtained from the soil with those from A. tridentata roots using non-parametric tests revealed no significant differences between the AMF present in these samples. In contrast, differences were observed between field and pot cultures samples. About 70% of the sequences obtained from field samples were within the Rhizophagus genus, while in pot cultures the dominant AMF were in the Claroideoglomus and Glomus genera. In addition, differences in AMF community composition were observed among sites. We are currently investigating whether these differences correlate with dissimilarities in edaphic characteristics. Overall, our results suggest that a diverse AMF flora is present in sagebrush habitats, although certain genotypes appear to be dominant.

Broader Impacts:

1 - Boise State Univeristy, Biological Sciences, 1910 University Drive, Boise, ID, 83725-1515, USA

Keywords:
mycorrhizae
sagebrush steppe.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PME003
Abstract ID:404
Candidate for Awards:None