Effects of dark septate endophytes on tomato plant performance

Non-mycorrhizal fungal root endophytes can be found in all natural and cultivated ecosystems, but little is known about their impact on plant performance. The impact of three mitosporic dark septate endophytes (DSE48, DSE49 and Leptodontidium orchidicola) on tomato plant characteristics was studied. Their effects on root and shoot growth, their influence on fruit yield and fruit quality parameters and their ability to diminish the impact of the pathogen Verticillium dahliae were investigated. While shoot biomass of young plants was enhanced between 10% and 20% by the endophytes DSE48 and L. orchidicola in one of two experiments and by DSE49 in both experiments, vegetative growth parameters of 24-week-old plants were not affected except a reproducible increase of root diameter by the isolate DSE49. Concerning fruit yield and quality, L. orchidicola could double the biomass of tomatoes and increased glucose content by 17%, but this was dependent on date of harvest and on root colonisation density. Additionally, the endophytes DSE49 and L. orchidicola decreased the negative effect of V. dahliae on tomato, but only at a low dosage of the pathogen. This indicates that the three dark septate endophytes can have a significant impact on tomato characters, but that the effects are only obvious at early stages of vegetative and generative development and currently too inconsistent to recommend the application of these DSEs in horticultural practice.     

Nitrogen form influences the response of Deschampsia antarctica to dark septate root endophytes

Fungi with dematiaceous septate hyphae, termed dark septate endophytes (DSE), are common in plant roots, particularly in cold-stressed habitats, but their effects on their host plants remain obscure. Here, we report a study that assessed the effects of six DSE on the growth and nutrient balance of Deschampsia antarctica when plants were supplied with the same amount of nitrogen in organic (casein hydrolysate) or inorganic (ammonium sulphate) form under controlled conditions. After 60 days, the DSE, that had each been isolated from D. antarctica and which analyses of internal transcribed spacer and large subunit regions indicated were similar to members of the Helotiales (Oculimacula yallundae, Mollisia and Tapesia spp.) and unassigned anamorphic ascomycetes, typically had no effect on, or reduced by 33–71%, shoot and root dry weights relative to uninoculated controls when plants had been supplied with nitrogen in inorganic form. In contrast, the DSE usually enhanced shoot and root dry weights by 51–247% when plants had been supplied with organic nitrogen. In the presence of inorganic nitrogen, only sporadic effects of DSE were recorded on shoot and root nitrogen or phosphorus concentrations, whereas in the presence of organic nitrogen, three to six of the DSE isolates increased shoot and root nitrogen and phosphorus contents. Most of the isolates decreased the phosphorus concentrations of shoots and roots when plants had been supplied with nitrogen in organic form. Our data suggest that DSE are able to mineralise peptides and amino acids in the rhizosphere, making nitrogen more freely available to roots.     

A meta-analysis of plant responses to dark septate root endophytes

? Dark septate endophytes (DSE) frequently colonize roots in the natural environment, but the effects of these fungi on plants are obscure, with previous studies indicating negative, neutral or positive effects on plant performance. ? In order to reach a consensus for how DSE influence plant performance, meta-analyses were performed on data from 18 research articles, in which plants had been inoculated with DSE in sterile substrates. ? Negative effects of DSE on plant performance were not recorded. Positive effects were identified on total, shoot and root biomass, and on shoot nitrogen (N) and phosphorus contents, with increases of 26-103% in these parameters for plants inoculated with DSE, relative to uninoculated controls. Inoculation increased total, shoot and root biomass by 52-138% when plants had not been supplied with additional inorganic N, or when all, or the majority, of N was supplied in organic form. Inoculation with the DSE Phialocephala fortinii was found to increase shoot and root biomass, shoot P concentration and shoot N content by 44-116%, relative to uninoculated controls. ? The analyses here suggest that DSE enhance plant performance under controlled conditions, particularly when all, or the majority, of N is available in organic form.     

Dark septate endophytes colonizing the roots of ‘non-mycorrhizal’ plants in a mine tailing pond and in a relatively undisturbed environment,Southwest China

Dark septate endophytes (DSEs), one of the most common fungal colonizers of roots, are considered to overlap in function with mycorrhizal fungi. However, there is little knowledge on the distribution and identity of DSEs in ‘non-mycorrhizal’ plants. In the current study, colonization and diversity of DSEs colonizing the roots of eight typically ‘non-mycorrhizal’ families were assessed. In total, 120 root samples of 31 plant species were all colonized by DSEs. Intensity of DSE colonization varied greatly among different plant species, with a range of 0.56–47.56%, 8.13% on average. Cladosporium, Cyphellophora and Phialophora were the dominant genera, with a relative abundance of more than 60% over a total of 90 isolates. Our results showed that diverse DSE species colonized the roots of ‘non-mycorrhizal’ plants, especially they were more common in degraded mine tailings than in the undisturbed site, but their integral roles to the functional roots are in need of further experimental demonstration.     

Responses of fungal root colonization,plant cover and leaf nutrients to long‐term exposure to elevated atmospheric CO2 and warming in a subarctic birch forest understory

Responses of the mycorrhizal fungal community in terrestrial ecosystems to global change factors are not well understood. However, virtually all land plants form symbiotic associations with mycorrhizal fungi, with approximately 20% of the plants' net primary production transported down to the fungal symbionts. In this study, we investigated how ericoid mycorrhiza (ErM), fine endophytes (FE) and dark septate endophytes (DSE) in roots responded to elevated atmospheric CO₂ concentrations and warming in the dwarf shrub understory of a birch forest in the subarctic region of northern Sweden. To place the belowground results into an ecosystem context we also investigated how plant cover and nutrient concentrations in leaves responded to elevated atmospheric CO₂ concentrations and warming. The ErM colonization in ericaceous dwarf shrubs increased under elevated atmospheric CO₂ concentrations, but did not respond to warming following 6 years of treatment. This suggests that the higher ErM colonization under elevated CO₂ might be due to increased transport of carbon belowground to acquire limiting resources such as N, which was diluted in leaves of ericaceous plants under enhanced CO₂. The elevated CO₂ did not affect total plant cover but the plant cover was increased under warming, which might be due to increased N availability in soil. FE colonization in grass roots decreased under enhanced CO₂ and under warming, which might be due to increased root growth, to which the FE fungi could not keep up, resulting in proportionally lower colonization. However, no responses in aboveground cover of Deschampsia flexuosa were seen. DSE hyphal colonization in grass roots significantly increased under warmer conditions, but did not respond to elevated CO₂. This complex set of responses by mycorrhizal and other root‐associated fungi to global change factors of all the fungal types studied could have broad implications for plant community structure and biogeochemistry of subarctic ecosystems.     

Colonization Characteristics and Composition of Dark Septate Endophytes (DSE) in a Lead and Zinc Slag Heap in Southwest China

The colonization characteristics and diversity of dark septate endophytes (DSE) associated with plants growing in a lead and zinc slag heap with a more than 250-year history in southwestern China were assessed. A total of 117 plant samples belonging to 29 species and 19 families were examined, and 97% (28/29) were colonized by dark septate fungal hyphae or microsclerotia. DSE colonization intensity varied greatly across plant species and also across individuals of the same species, showing a hyphal colonization range of 0.0–35.7%. In total, 38 melanized root-associated fungi with various morphological characteristics were isolated and 82% (31/38) of fungi were closely related to well-known DSE fungi, such as Exophiala spp., Phialophora (= Cadophora) spp., Phialocephala spp., and Leptodontidium spp. Among these, Phialophora and Exophiala were the dominant genera. Our results showed that DSE dominantly colonized the roots of the pioneer plants growing in such an ancient Pb-Zn slag heap. By contributing to metal tolerance and nutrient acquisition, DSE may be integral to the function of metal mine ecosystems.     

The co-occurrence of ectomycorrhizal,arbuscular mycorrhizal,and dark septate fungi in seedlings of four members of the Pinaceae

Although roots of species in the Pinaceae are usually colonized by ectomycorrhizal (EM) fungi, there are increasing reports of the presence of arbuscular mycorrhizal (AM) and dark septate endophytic (DSE) fungi in these species. The objective of this study was to determine the colonization patterns in seedlings of three Pinus (pine) species (Pinus banksiana, Pinus strobus, Pinus contorta) and Picea glauca x Picea engelmannii (hybrid spruce) grown in soil collected from a disturbed forest site. Seedlings of all three pine species and hybrid spruce became colonized by EM, AM, and DSE fungi. The dominant EM morphotype belonged to the E-strain category; limited colonization by a Tuber sp. was found on roots of Pinus strobus and an unknown morphotype (cf. Suillus–Rhizopogon group) with thick, cottony white mycelium was present on short roots of all species. The three fungal categories tended to occupy different niches in a single root system. No correlation was found between the percent root colonized by EM and percent colonization by either AM or DSE, although there was a positive correlation between percent root length colonized by AM and DSE. Hyphae and vesicles were the only AM intracellular structures found in roots of all species; arbuscules were not observed in any roots.     

Contrasting impacts of defoliation on root colonization by arbuscular mycorrhizal and dark septate endophytic fungi of Medicago sativa

Individual plants typically interact with multiple mutualists and enemies simultaneously. Plant roots encounter both arbuscular mycorrhizal (AM) and dark septate endophytic (DSE) fungi, while the leaves are exposed to herbivores. AMF are usually beneficial symbionts, while the functional role of DSE is largely unknown. Leaf herbivory may have a negative effect on root symbiotic fungi due to decreased carbon availability. However, evidence for this is ambiguous and no inoculation-based experiment on joint effects of herbivory on AM and DSE has been done to date. We investigated how artificial defoliation impacts root colonization by AM (Glomus intraradices) and DSE (Phialocephala fortinii) fungi and growth of Medicago sativa host in a factorial laboratory experiment. Defoliation affected fungi differentially, causing a decrease in arbuscular colonization and a slight increase in DSE-type colonization. However, the presence of one fungal species had no effect on colonization by the other or on plant growth. Defoliation reduced plant biomass, with this effect independent of the fungal treatments. Inoculation by either fungal species reduced root/shoot ratios, with this effect independent of the defoliation treatments. These results suggest AM colonization is limited by host carbon availability, while DSE may benefit from root dieback or exudation associated with defoliation. Reductions in root allocation associated with fungal inoculation combined with a lack of effect of fungi on plant biomass suggest DSE and AMF may be functional equivalent to the plant within this study. Combined, our results indicate different controls of colonization, but no apparent functional consequences between AM and DSE association in plant roots in this experimental setup.     

Lulwoana sp., a dark septate endophyte in roots of Posidonia oceanica (L.) Delile seagrass

Posidonia oceanica is the most common, widespread and important monocotyledon seagrass in the Mediterranean Basin, and hosts a large biodiversity of species, including microorganisms with key roles in the marine environment. In this study, we ascertain the presence of a fungal endophyte in the roots of P. oceanica growing on different substrata (rock, sand and matte) in two Sicilian marine meadows. Staining techniques on root fragments and sections, in combination with microscope observations, were used to visualise the fungal presence and determine the percentage of fungal colonisation (FC) in this tissue. In root fragments, statistical analysis of the FC showed a higher mean in roots anchored on rock than on matte and sand. In root sections, an inter‐ and intracellular septate mycelium, producing intracellular microsclerotia, was detected from the rhizodermis to the vascular cylinder. Using isolation techniques, we obtained, from both sampling sites, sterile, slow‐growing fungal colonies, dark in colour, with septate mycelium, belonging to the dark septate endophytes (DSEs). DNA sequencing of the internal transcribed spacer (ITS) region identified these colonies as Lulwoana sp. To our knowledge, this is the first report of Lulwoana sp. as DSE in roots of P. oceanica. Moreover, the highest fungal colonisation, detected in P. oceanica roots growing on rock, suggests that the presence of the DSE may help the host in several ways, particularly in capturing mineral nutrients through lytic activity.     

Characterization of Novel Plant Growth Promoting Endophytic Bacterium <Emphasis Type="Italic">Achromobacter xylosoxidans</Emphasis> from Wheat Plant

Nine diazotrophic bacteria were isolated from surface-sterilized roots and culms of wheat variety Malviya-234, which is grown with very low or no inputs of nitrogen fertilizer. Out of the nine bacteria, four showed indole acetic acid (IAA) production, and five were positive for P solubilization. One isolate, WM234C-3, showed appreciable level of nitrogenase activity, IAA production, and P solubilization ability, and was further characterized with a view to exploiting its plant growth promoting activity. Based on 16S rDNA sequence analysis, this isolate was identified as Achromobacter xylosoxidans. Diazotrophic nature of this particular isolate was confirmed by Western blot analysis of dinitrogenase reductase and amplification of nifH. Analysis of the nifH sequence showed close homology with typical diazotrophic bacteria. Endophytic nature and cross-infection ability of WM234C-3 were tested by molecular tagging with gusA fused to a constitutive promoter followed by inoculation onto rice seedlings in axenic conditions. At 21 days after inoculation, the roots showed blue staining, the most intense color being at the emergence of lateral roots and root tips. Microscopic observation confirmed colonization of gus-tagged WM234C-3 in the intercellular spaces of cortical as well as vascular zones of roots. Inoculation of gus-tagged WM234C-3 to rice plants resulted in significant increase in root/shoot length, fresh weight, and chlorophyll a content. Plant growth promoting features coupled with cross-infection ability suggest that this endophytic bacterium may be exploited as agricultural agent for various crops after a thorough and critical pathogenicity test.     

Red list plants: colonization by arbuscular mycorrhizal fungi and dark septate endophytes

Since information concerning the mycorrhization of endangered plants is of major importance for their potential re-establishment, we determined the mycorrhizal status of Serratula tinctoria (Asteraceae), Betonica officinalis (Lamiaceae), Drosera intermedia (Droseraceae) and Lycopodiella inundata (Lycopodiaceae), occurring at one of two wetland sites (fen meadow and peat bog), which differed in soil pH and available P levels. Root colonization by arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) was quantified. Colonization by AMF appeared to be more frequent in the fen meadow than in the peat bog, and depended on the host plant. Roots of S. tinctoria and B. officinalis were well colonized by AMF in the fen meadow (35–55% root length) and both arbuscules and vesicles were observed to occur in spring as well as in autumn. In the peat bog, L. inundata showed a low level of root colonization in spring, when vesicles were found frequently but no arbuscules. In roots of D. intermedia from the peat bog, arbuscules and vesicles were observed, but AMF colonization was lower than in L. inundata. In contrast, the amount of AMF spores extracted from soil at the peat bog site was higher than from the fen meadow soil. Spore numbers did not differ between spring and autumn in the fen meadow, but they were higher in spring than in autumn in the peat bog. Acaulospora laevis or A. colossica and Glomus etunicatum were identified amongst the AMF spores extracted from soil at the two sites. S. tinctoria and B. officinalis roots were also regularly colonized by DSE (18–40% root length), while L. inundata was only rarely colonized and D. intermedia did not seem to be colonized by DSE at all.     

Fungal community structure under goat willows (Salix caprea L.) growing at metal polluted site: the potential of screening in a model phytostabilisation study

Goat willow (Salix caprea L.) was selected in a previous vegetation screening study as a potential candidate for the later-stage phytostabilisation efforts at a heavily metal polluted site in Slovenia. The aims of this study were to identify the fungi colonising roots of S. caprea along the gradient of vegetation succession and to estimate their colonisation levels in relation to metal pollution in order to reveal its mycorrhizal status at the site. Additionally the metal accumulation capacity of S. caprea and photosynthetic pigments were analysed as indications of its fitness at four differentially polluted plots. Despite high concentrations of leaf accumulated Cd, no significant differences in photosynthetic pigment concentrations were observed. The roots were colonised by arbuscular mycorrhizal (AM) fungi, ectomycorrhizal (EM) fungi, and dark septate endophytes (DSE), with EM as the dominant type on all the plots. Molecular characterisation showed poor correlation of the root EM community with the above-ground sporocarp diversity. Members of Sordariaceae were the most frequent colonisers with an average colonisation of 21% of all root tips, followed by Thelephoraceae with 10%. DSE colonisation increased with increasing Pb concentrations and decreasing organic matter (OM).     

Dual inoculation of dark septate endophytes and Trichoderma viride drives plant performance and rhizosphere microbiome adaptations of Astragalus mongholicus to drought

Rhizosphere microbiome adapts their structural compositions to water scarcity and have the potential to mitigate drought stress of plants. To unlock this potential, it is crucial to understand community responses to drought in the interplay between soil properties, water management and exogenous microbes interference. Inoculation with dark septate endophytes (DSE) (Acrocalymma vagum, Paraboeremia putaminum) and Trichoderma viride on Astragalus mongholicus grown in the non-sterile soil was exposed to drought. Rhizosphere microbiome were assessed by Illumina MiSeq sequencing of the 16S and ITS2 rRNA genes. Inoculation positively affected plant growth depending on DSE species and water regime. Ascomycota, Proteobacteria, Actinobacteria, Chloroflexi and Firmicutes were the dominant phyla. The effects of dual inoculation on bacterial community were greater than those on fungal community, and combination of P. putaminum and T. viride exerted a stronger impact on the microbiome under drought stress. The observed changes in soil factors caused by inoculation could be explained by the variations in microbiome composition. Rhizosphere microbiome mediated by inoculation exhibited distinct preferences for various growth parameters. These findings suggest that dual inoculation of DSE and T. viride enriched beneficial microbiota, altered soil nutrient status and might contribute to enhance the cultivation of medicinal plants in dryland agriculture.     

Inoculation of<Emphasis Type="Italic">Rhododendron</Emphasis> cv. Belle-Heller with two strains of<Emphasis Type="Italic">Phialocephala fortinii</Emphasis> in two different substrates

The growth response of an ornamentalRhododendron hybrid to the inoculation withPhialocephala fortinii was studied in two pot experiments in order to decide about the effectiveness of the inoculation of young rhododendron microplants. Two different substrates were used in both experiments, either sterilized or non-sterilized: a horticultural substrate and a soil collected from a field site with dominant ericoid vegetation. Two fungal isolates were used for an inoculation:P. fortinii strain P (UAMH 8433) andP. fortinii strain F, a dark septate endophyte (DSE) previously isolated from naturally-infected roots ofVaccinium myrtillus. BothPhialocephala strains successfully colonized the roots of the host plants forming typical DSE (=pseudomycorrhizal) colonization pattern including the formation of intracellular microsclerotia. However, pseudomycorrhizal colonization did not affect the growth parameters of the host rhododendrons. The results from both experiments indicate a neutral effect of the inoculation with DSE fungi on the growth ofRhododendron cv. Belle-Heller.     

Variations in ergosterol content and ornithine decarboxylase activity of ectomycorrhizal root-soil systems

Influences of soil P fertilization on temporal changes in ergosterol content and ornithine decarboxylase (E.C. 4.1.1.17, ODC) activity were monitored in rhizosphere soil, non-rhizosphere soil and Pinus contorta roots ectomycorrhizal with Hebeloma crustuliniforme grown in a loamy sand. With addition of mycorrhizal inoculum to loamy sand, ODC activity mg^-1 root increased between 10% and 2 fold within 21 weeks of pianting. Inoculation also decreased root mass per seedling. Inoculation increased mycelia mass per root mass by up to 2 fold but no differences were observed for total seedling mass until 35 weeks. Intramatrical mycelia were detrimental to early plant growth, but inoculated seedlings had 1.7 times more root mass and 1.3 times more shoot mass at 35 weeks. Rhizosphere soil contained up to 5 times more mycelia and up to 6 times greater ODC activity than non-rhizosphere soil. Inoculation increased rhizophere metabolic activity and intramatrical mycelia mass. Their sensitivity to fungal inoculation, P fertilization and temporal trends may make the methods useful in studies of rhizosphere ecology and root-microbe relationships.     

Dark Septate Root Endophytic Fungus <Emphasis Type="Italic">Nectria haematococca</Emphasis> Improves Tomato Growth Under Water Limiting Conditions

The ascomycetous dark septate endophytic (DSE) fungi characterized by their melanized hyphae can confer abiotic stress tolerance in their associated plants in addition to improving plant growth and health. In this study inoculation of the DSE fungus Nectria haematococca Berk. & Broome significantly improved all the plant growth parameters like the plant height, stem girth, leaf characteristics and plant biomass of drought-stressed tomato. Root characters like the total root length, primary root diameter, 2nd order root number and diameter, root hair number and length were also significantly influenced by the fungal inoculation. Nevertheless, N. haematococca inoculation did not affect root colonization by native arbuscular mycorrhizal (AM) fungi and no significant correlation existed between the AM and DSE fungal variables examined. The proline accumulation in shoots of N. haematococca inoculated plants was significantly higher than uninoculated plants. The present study clearly indicates for the first time the ability of the DSE fungus, N. haematococca in inducing the drought stress tolerance and promoting the growth of the host plant under water stress.     

Ectomycorrhizae,arbuscular mycorrhizae,and dark-septate fungi on <Emphasis Type="Italic">Salix humboldtiana</Emphasis> in two riparian populations from central Argentina

Colonization of Salix humboldtiana (Salicaceae) by ectomycorrhizae (ECM), arbuscular mycorrhizae (AM), and dark-septate endophytic (DSE) fungi was studied throughout autumn on two riparian populations in central Argentina. AM and DSE infection on roots ranged from 0% to 17% and from 2% to 20% respectively, whereas ECM colonization was higher, varying between 33% and 99% for both sites. Seven ECM morphotypes were found on S. humboldtiana roots. The nuclear rDNA internal transcriber spacer (ITS) region from the ectomycorrhizal root tips was amplified using ITS-1F and ITS-4 primers. Two of the seven ECM types were identified by searching GenBank blasts: one attributed to the genus Tomentella (Thelephoraceae) and the second most closely matched to Inocybe sp. (Cortinariaceae). The ECM colonization varied among sampling dates and sites, whereas AM and DSE colonization varied only among sampling dates. Diversity values for the ECM morphotype were not significantly different for autumn months or among the two sites. Positive correlations were found between Inocybe sp. and sites and between Inocybe sp., Tomentella sp., morphotypes III, IV, and VI, and sampling dates. This article provides the first documented evidence of co-occurrence of ECM, AM, and DSE in S. humboldtiana.     

Arbuscular mycorrhizas and dark septate endophytes in bromeliads from South American arid environment

Most plant roots are associated with glomalean fungi forming arbuscular mycorrhizas (AM) and a wide range are also colonized by ascomycetous dark septate endophytes (DSE). Bromeliaceae species can be epiphytic, rupicolous or terrestrial but their mycorrhizal status is poorly studied. We examined the AM and DSE status of 5 epiphytic and 4 terrestrial Bromeliaceae from an arid area of Central Argentina. The terrestrial species were either dually associated (AM and DSE) or non-associated whereas the epiphytes were only DSE colonized. Terrestrial Bromeliaceae that formed AM-DSE associations were likely responding to the arid conditions of the area and the availability of AM fungal (AMF) spores in the soil. The terrestrialBromelia ubaniana was not colonized either by AMF or DSE. This could reflect its root morphology and high number of root hairs. DSE are endosymbiotic in the stressful ecosystems experienced by canopy epiphytes in the studied environment. The different fungal associations are discussed in relation to the three Bromeliaceae subfamiles and we suggest that environmental features determinethe type of association formed by species in this plant family.     

福廷瓶头霉与马尾松的共生特征

深色有隔内生真菌（dark septate endophyte,DSE）广泛定殖于植物根系,对促进植物生长、提高植物抗逆能力具重要作用。本研究从马尾松Pinus massoniana根系分离到一株DSE,于无菌条件下研究了此菌与马尾松的共生特征,研究结果表明：基于形态学和分子生物学分析,此菌被鉴定为福廷瓶头霉Phialocephala fortinii,在PDA培养基25℃培养条件下,此菌不产孢,菌丝深色、具隔,最适培养基为PDA。此菌与马尾松根系共生体的形成过程可划分为3个时期,即侵入前期：接种后2d,新生菌丝向马尾松根系定向生长并开始接触根系,但未侵入根系内部;侵入期：接种后4d,菌丝与马尾松根系接触侵入根内并在根系皮层细胞间扩展延伸;形成期：接种后6d,菌丝继续在马尾松根系内扩展并形成富含脂类物质的微菌核。接种福廷瓶头霉显著增加了马尾松生物量的积累（P<0.05）,并影响了其根系发育。接种后,马尾松主根生长受限,侧根生长显著提高（P<0.05）,侧根长度较未接种处理增加了112.87%。被侵染根系的根毛数量减少,并由大量根外菌丝包裹。以上结果对进一步揭示DSE与宿主的共生机理有一定指导意义。     

Medicinal plants as hosts of arbuscular mycorrhizal fungi and dark septate endophytes

Arbuscular mycorrhizal and dark septate endophyte associations of 31 medicinal plant species collected from the Garden of Medicinal Plants of the Faculty of Pharmacy, Jagiellonian University, Collegium Medicum in Kraków were investigated. Arbuscular mycorrhiza (AM) was found in 30 species; 23 were of the Arum-type, 5—Paris and 2 taxa revealed intermediate morphology. Many plants were strongly colonized by arbuscular mycorrhizal fungi (AMF). The mycelium of dark septate endophytes (DSE) was observed in 21 taxa. However, the percentage of root colonization by these fungi was low. Spores of 15 species of AMF (Glomeromycota) were found in the rhizosphere of the investigated plants. Our results are the first detailed report of both AMF and DSE associations of these plant species. The use of AMF and DSE during the process of medicinal plant cultivation for pharmaceutical purposes is discussed.