Fungal root endophytes from natural vegetation in Mediterranean environments with special reference to Fusarium spp

Abstract

Surveys (in 2002 and 2003) were performed for fungal endophytes in roots of 24 plant species growing at 12 sites (coastal and inland soils, both sandy soils and salt marshes) under either water or salt stress in the Alicante province (Southeast Spain). All plant species examined were colonized by endophytic fungi. A total of 1830 fungal isolates were obtained and identified by morphological and molecular [internal transcribed spacer (ITS) and translation elongation factor-1alpha gene region (TEF-1alpha) sequencing] techniques. One hundred and forty-two fungal species were identified, belonging to 57 genera. Sterile mycelia were assigned to 177 morphospecies. Fusarium and Phoma species were the most frequent genera, followed by Aspergillus, Alternaria and Acremonium. Fungal root endophytic communities were influenced by the soil type where their respective host plants grew, but not by location (coastal or inland sites). Fusarium oxysporum, Aspergillus fumigatus and Alternaria chlamydospora contributed most to the differences found between endophytic communities from sandy and saline soils. Host preference was found for three Fusarium species studied. Fusarium oxysporum and Fusarium solani were especially isolated from plants of the family Leguminosae, while Fusarium equiseti showed a preference for Lygeum spartum (Gramineae). In some cases, specificity could be related to intra-specific variability as shown by sequencing of the TEF-1alpha in the genus Fusarium.

Fungal Assemblages Associated with Roots of Halophytic and Non-halophytic Plant Species Vary Differentially Along a Salinity Gradient

“…Comparisons between the herein recovered fungal diversity and that obtained in other works are difficult due to the relative scarcity of similar samplings. In general terms, we cannot conclude that the fungal community reported here is highly divergent from that found in other studies (e.g., [16,[42][43][44]). Most fungi identified are common endophytes and soil dwellers, albeit, in other cases, BLAST identities matched uncultured fungi, indicating a possible novelty in the strains.…”

“…S3 in the ESM). Other examples of this transition, including the same orders and soil conditions, have been previously reported [16]. This suggests general adaptations to these specific situations (e.g., soil salinity) at a high taxonomical level.…”

“…Dittrichia viscosa L.) is a ubiquitous and nitrophilous species, which is, to some extent, tolerant to salt but cannot be considered a halophyte [15]. A previous characterization of fungal root endophytic communities in sand dunes and salt marshes in SE Spain showed a tendency of fungal assemblages to change according to either of the two soil conditions at a larger scale [16]. The aim of this study was to compare fungal root endophytic communities between the halophytic and non-halophytic Inula species along a gradient to assess how spatial patterns of distribution are influenced by the host or soil conditions.…”

Natural occurrence of fungal egg parasites of root-knot nematodes, Meloidogyne spp. in organic and integrated vegetable production systems in Spain

“…d F-values, degrees of freedom, and P values to compare parasitism, richness, H 0 , and J 0 between organic and integrated production consider a parasite. Three out the four remaining fungi, Cladosporium tenuissimum, Penicillium citrinum, and P. olsonii, have been reported as endophytes (Fisher and Petrini 1992;Vega et al 2006;Maciá-Vicente et al 2008), and F. verticillioides as a plant pathogen, but as far as we know, their capacity to parasitize nematode eggs has not been investigated. Higher levels of parasitism were found in organic than integrated production.…”

Molecular Characterization of Fusarium globosum Strains from South African Maize and Japanese Wheat

“…Finally, accessions DQ854859, DQ85460 and DQ854461 were derived from strains attributed to Spanish isolates of F. globosum [23]. However, these three sequences are 100% homologous to the TEF-1α sequences for F. proliferatum strains ITEM 1590 and ITEM 1874, which strongly suggests that these three Spanish strains are probably F. proliferatum and not F. globosum.…”