Phylogenetic reference data for systematics and phylotaxonomy of arbuscular mycorrhizal fungi from phylum to species level

Abstract

Summary Although the molecular phylogeny, evolution and biodiversity of arbuscular mycorrhizal fungi (AMF) are becoming clearer, phylotaxonomically reliable sequence data are still limited. To fill this gap, a data set allowing resolution and environmental tracing across all taxonomic levels is provided. Two overlapping nuclear DNA regions, totalling c. 3 kb, were analysed: the small subunit (SSU) rRNA gene (up to 1800 bp) and a fragment spanning c. 250 bp of the SSU rDNA, the internal transcribed spacer (ITS) region (c. 475–520 bp) and c. 800 bp of the large subunit (LSU) rRNA gene. Both DNA regions together could be analysed for 35 described species, the SSU rDNA for c. 76 named and 18 as yet undefined species, and the ITS region or LSU rDNA, or a combination of both, for c. 91 named and 16 as yet undefined species. Present phylogenetic analyses, based on the three rDNA markers, provide reliable and robust resolution from phylum to species level. Altogether, 109 named species and 27 cultures representing as yet undefined species were analysed. This study provides a reference data set for molecular systematics and environmental community analyses of AMF, including analyses based on deep sequencing.

The plasma membrane proteome of Medicago truncatula roots as modified by arbuscular mycorrhizal symbiosis

“…Mycorrhizal inoculation was realized by adding Epoisses soil-based inoculum (spores, roots, and hyphae) of the AM fungus R. irregularis DAOM 197198 (Kruger et al 2012). Seedlings (three per pot) were grown for 4 weeks under controlled conditions (16 h photoperiod, 23°C/18°C day/night, 60% relative humidity, 220 μEinstein m −2 .s −1 photon flux density).…”

The expression of GintPT, the phosphate transporter of Rhizophagus irregularis, depends on the symbiotic status and phosphate availability

“…Rhizophagus irregularis (DAOM 197198), recently reassigned from Glomus intraradices Schenck and Smith (Krüger et al 2012), was produced in monoaxenic cultures maintained on Agrobacterium rhizogenes-transformed chicory roots (Bécard and Fortin 1988) in twocompartment Petri plates, as described in Pérez-Tienda et al (2011). Plates were incubated in the dark at 24 °C until the fungal compartment, which contained a solid M medium without sucrose (M-C medium), was profusely colonized by the fungus (approximately 6 weeks).…”

“…For instance, field experiments have shown that some AM fungi, such as Rhizophagus irregularis (Syn. Glomus intraradices; Krüger et al 2012), are deemed more tolerant to a high Pi concentration, while other species are absent under this nutrient condition (Verbruggen and Kiers 2010). High Pi availability enhances root growth and reduces the colonized versus non-colonized root length ratio (Smith et al 1992;Marschner 1995;.…”

Genetic and genomic glimpses of the elusive arbuscular mycorrhizal fungi

“…The genus name Glomus, in particular, has been used for fungi that are so diverse that they should be in several different families. A major new molecular phylogenetic study, based on ribosomal RNA genes of almost all available AMF cultures, provides the support for a radical rationalization of AMF names [ 5]. For example, the frequently studied Glomus intraradicesDAOM197198, which was recently reidentified as G. irregulare [ 11] has now become Rhizophagus irregularis.…”

“…AMF researchers were therefore well placed when the wave of next-generation sequencing hit environmental microbiology, and recent papers have used massive sequencing to reveal yet more diversity [15, 16 and 17]. In the light of these data, the 230 morphospecies described so far in the Glomeromycota [5] appear as a sensational underestimate.…”