Only a Few Fungal Species Dominate Highly Diverse Mycofloras Associated with the Common Reed

Abstract

Plants are naturally colonized by many fungal species that produce effects ranging from beneficial to pathogenic. However, how many of these fungi are linked with a single host plant has not been determined. Furthermore, the composition of plant-associated fungal communities has not been rigorously determined. We investigated these essential issues by employing the perennial wetland reed Phragmites australis as a model. DNA extracted from roots, rhizomes, stems, and leaves was used for amplification and cloning of internal transcribed spacer rRNA gene fragments originating from reed-associated fungi. A total of 1,991 clones from 15 clone libraries were differentiated by restriction fragment length polymorphism analyses into 345 operational taxonomical units (OTUs). Nonparametric estimators for total richness (Chao1 and ACE) and also a parametric log normal model predicted a total of about 750 OTUs if the libraries were infinite. Sixty-two percent of the OTUs sequenced were novel at a threshold of 3%. Several of these OTUs represented undocumented fungal species, which also included higher taxonomic levels. In spite of the high diversity of the OTUs, the mycofloras of vegetative organs were dominated by just a few typical fungi, which suggested that competition and niche differentiation influence the composition of plant-associated fungal communities. This suggestion was independently supported by the results of nested PCR assays specifically monitoring two OTUs over 3 years, which revealed significant preferences for host habitat and host organ.

Soil conditioning effects ofPhragmites australison native wetland plant seedling survival

“…However, identities of soil fungi that may contribute to reduced seedling survival remain unknown. Although EU is known to host diverse assemblages of fungi (Angelini et al., 2012; Fischer & Rodriguez, 2013; Neubert, Mendgen, Brinkmann, & Wirsel, 2006; Wirsel, Leibinger, Ernst, & Mendgen, 2001), their specific roles in limiting seedling survival are largely unknown. Similarly, EU and NA also associate with diverse communities of oomycetes (Belzile et al., 2010; Chambers et al., 1999, 2003; Jodoin et al., 2008; McCormick et al., 2010a,b; Nechwatal & Mendgen, 2006; Nechwatal, Wielgoss, & Mendgen, 2005, 2008; Nelson & Karp, 2013) that are known to affect plant survival and would have been inhibited by the broad‐spectrum fungicide used.…”

Mycoparasitism of Endophytic Fungi Isolated From Reed on Soilborne Phytopathogenic Fungi and Production of Cell Wall-Degrading Enzymes In Vitro

“…isolate 5/97-12, Mt2W3C4 were isolated from roots of common reed (P. australis) in the littoral of Lake Constance (Germany). Details concerning the location and the molecular characterization have been published previously [31,39].…”

“…(isolate 5/97-12, Mt2W3C4) have been isolated from common reed (Phragmites australis) in the littoral of Lake Constance (Germany) [31]. Preliminary tests suggested antagonism against several soilborne fungal pathogens.…”

Fungal endophytes and their interaction with plant pathogens: a review

“…As a result, the real number of endophytic species in a sample can be underestimated. Non culturable endophytes do exist, and fortunately some techniques allowing their detection in plant tissues have been developed (Neubert et al, 2006;Duong et al, 2006;Gallery et al, 2007).…”

“…Neubert et al, 2006). Singleton species are the main factor driving non-asymptotically species accumulation curves.…”