01943nas a2200193   4500008004100000245010200041210006900143300001300212490000800225520126600233653003401499653002101533653003701554653002701591100001801618700001201636700001801648856008301666       2013                        eng d00aArabidopsis thaliana model system reveals a continuum of responses to root endophyte colonization0 aArabidopsis thaliana model system reveals a continuum of respons  a250 -2600 v1173 a<p>We surveyed the non-mycorrhizal model plant Arabidopsis thaliana microscopically for its ability to form dark septate endophyte (DSE) symbioses in field, greenhouse, and laboratory studies. The laboratory studies were also used to estimate host growth responses to 34 Periconia macrospinosa and four Microdochium sp. isolates. Consistent with broad host range observed in previous experiments, field-, greenhouse-, and laboratory-grown A. thaliana were colonized by melanized inter- and intracellular hyphae and microsclerotia or chlamydospores indicative of DSE symbiosis. Host responses to colonization were variable and depended on the host ecotype. On average, two A. thaliana accessions (Col-0 and Cvi-0) responded negatively, whereas one (Kin-1) was unresponsive, a conclusion consistent with our previous analyses with forbs native to the field site where the fungi originate. Despite the average negative responses, examples of positive responses were also observed, a conclusion also congruent with earlier studies. Our results suggest that A. thaliana has potential as a model for more detailed dissection of the DSE symbiosis. Furthermore, our data suggest that host responses are controlled by variability in the host and endophyte genotypes.</p>10aDark septate endophytes (DSE)10aMicrodochium sp.10aMutualism–parasitism continuum10aPericonia macrospinosa1 aMandyam, K.G.1 aRoe, J.1 aJumpponen, A.  uhttps://www.sciencedirect.com/science/article/pii/S1878614613000226?via%3Dihub02449nas a2200181   4500008004100000245010500041210006900146300001300215490000700228520182000235653003402055653003702089653002702126100001802153700001202171700001802183856006602201       2012                        eng d00aSeptate endophyte colonization and host responses of grasses and forbs native to a tallgrass prairie0 aSeptate endophyte colonization and host responses of grasses and  a109 -1190 v223 a<p>Native tallgrass prairies support distinct dark septate endophyte (DSE) communities exemplified by Periconia macrospinosa and Microdochium sp. that were recently identified as common root symbionts in this system. Since these DSE fungi were repeatedly isolated from grasses and forbs, we aimed to test their abilities to colonize different hosts. One Microdochium and three Periconia strains were screened for colonization and growth responses using five native grasses and six forbs in an in vitro system. Previously published data for an additional grass (Andropogon gerardii) were included and reanalyzed. Presence of indicative inter- and intracellular structures (melanized hyphae, microsclerotia, and chlamydospores) demonstrated that all plant species were colonized by the DSE isolates albeit to varying degrees. Microscopic observations suggested that, compared to forbs, grasses were colonized to a greater degree in vitro. Host biomass responses varied among the host species. In broad comparisons, more grass species than forbs tended to respond positively to colonization, whereas more forb species tended to be non-responsive. Based on the suspected differences in the levels of colonization, we predicted that tallgrass prairie grasses would support greater DSE colonization than forbs in the field. A survey of field-collected roots from 15 native species supported this hypothesis. Our study supports the &ldquo;broad host range&rdquo; of DSE fungi, although the differences in the rates of colonization in the laboratory and in the field suggest a greater compatibility between grasses and DSE fungi. Furthermore, host responses to DSE range from mutualism to parasitism, suggesting a genotype-level interplay between the fungi and their hosts that determines the outcome of this symbiosis.</p>10aDark septate endophytes (DSE)10aMutualism–parasitism continuum10aMycorrhizal dependency1 aMandyam, K.G.1 aFox, C.1 aJumpponen, A.  uhttps://link.springer.com/article/10.1007%2Fs00572-011-0386-y