Diversity of arbuscular mycorrhizal fungi colonising roots of the grass species Agrostis capillaris and Lolium perenne in a field experiment

Abstract

Analysis of arbuscular mycorrhizal (AM) fungal diversity through morphological characters of spores and intraradicular hyphae has suggested previously that preferential associations occur between plants and AM fungi. A field experiment was established to investigate whether AM fungal diversity is affected by different host plants in upland grasslands. Indigenous vegetation from plots in an unimproved pasture was replaced with monocultures of either Agrostis capillaris or Lolium perenne. Modification of the diversity of AM fungi in these plots was evaluated by analysis of partial sequences in the large subunit (LSU) ribosomal RNA (rDNA) genes. General primers for AM fungi were designed for the PCR amplification of partial sequences using DNA extracted from root tissues of A. capillaris and L. perenne. PCR products were used to construct LSU rDNA libraries. Sequencing of randomly selected clones indicated that plant roots were colonised by AM fungi belonging to the genera Glomus, Acaulospora and Scutellospora. There was a difference in the diversity of AM fungi colonising roots of A. capillaris and L. perenne that was confirmed by PCR using primers specific for each sequence group. These molecular data suggest the existence of a selection pressure of plants on AM fungal communities.

Effects of different management practices on arbuscular mycorrhizal fungal diversity in maize fields by a molecular approach

“…Lack of detection of Archaeosporaceae in both samples (maize roots and soils) did not probably depend on the primers used since NS31/AM1 successfully amplified many Archaeospora sequences from Collinsia sparsiflora roots in Californian soils (Schechter and Bruns 2008). On the other hand, whilst Archaeospora species have frequently been found in trap cultures, they have never been detected in arable soils (Hijri et al 2006), which is in agreement with the results of other molecular studies on AMF communities in Central Europe (Daniell et al 2001;Vandenkoornhuyse et al 2002;Gollotte et al 2004;Scheublin et al 2004;Renker et al 2005;Börstler et al 2006).…”

Changes in the composition of native root arbuscular mycorrhizal fungal communities during a short-term cover crop-maize succession

“…AMF community composition has long been known to be more dependent on host plant identity (Helgason et al 2002;Vandenkoornhuyse et al 2003;Gollotte, et al 2004;Scheublin et al 2004;Sýkorová et al 2007) than on habitat (Becklin et al 2012), season (Davison et al 2011), phosphorus levels (Gosling et al 2013) or land use intensity (Vályi et al 2015). Indeed, some authors hypothesized that AMF communities are not random assemblages, but are associated with ecological groups of plant species showing specific traits (habitat generalist vs forest specialist) (Davison et al 2011).…”

Identification of Bacterial Groups Preferentially Associated with Mycorrhizal Roots of Medicago truncatula

“…AM are ancient; the first fossil evidence of this symbiosis dates back 400 million years (33). Several authors have proposed that AM have contributed to the colonization of early land plants (32,38).AM are generally assumed to be nonspecific associations, since Glomeromycota are able to colonize roots of several host plants and are themselves colonized by different AM fungal species (12,14,35,44). Despite this lack of host specificity, the diversity of AM fungi has been shown to affect the plant community composition under field conditions (43), and the genetic structure of the AM fungal community was shown to differ significantly according to the plant species…”

“…AM are generally assumed to be nonspecific associations, since Glomeromycota are able to colonize roots of several host plants and are themselves colonized by different AM fungal species (12,14,35,44). Despite this lack of host specificity, the diversity of AM fungi has been shown to affect the plant community composition under field conditions (43), and the genetic structure of the AM fungal community was shown to differ significantly according to the plant species (B. Pivato, P. Lemanceau, S. Siblot, G. Berta, C. Mougel, and D. van Tuinen, submitted for publication).…”

“…Furthermore, the corresponding studies did not take into account the natural diver-sity of AM fungi, since they were based on the inoculation of selected strains of Glomeromycota. However, under field conditions, plants are generally colonized by several types of functionally different Glomeromycota (12,13,14,44; Pivato et al, submitted). Therefore, the inoculation of specific strains of Glomeromycota to assess their impact on the indigenous bacterioflora may have induced bias.…”