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Dark septate root endophytes (DSE) are conidial or sterile fungi (Deuteromycotina, Fungi Imperfecti) likely to be ascomycetous and colonizing plant roots. They have been reported for nearly 600 plant species representing about 320 genera and 100 families. DSE fungi occur from the tropics to arctic and alpine habitats and comprise a heterogeneous group that functionally and ecologically overlaps with soil fungi, saprotrophic rhizoplane-inhabiting fungi, obligately and facultatively pathogenic fungi and mycorrhizal fungi. Numerous species of undescribed sterile and anamorphic taxa may also await discovery. Although DSE are abundant in washed root and soil samples from various habitats, and are easily isolated from surface-sterilized roots of ecto-, ectendo-, endo- and non-mycorrhizal host species, their ecological functions are little understood. Studies of DSE thus far have yielded inconsistent results and only poorly illustrate the role of DSE in their natural habitats. These inconsistencies are largely due to the uncertain taxonomic affinities of the strains of DSE used. In addition, because different strains of a single anamorph taxon seem to vary greatly in function, no clear generalizations on their ecological role have been drawn. This paper reviews the current literature on DSE and the ecology and discusses the need for and direction of future research.

Long-term preservation of experimental fungi without genetic, morphological, and pathogenic changes is of paramount importance in mycological and plant pathological investigations. Several cryogenic and non-cryogenic methods are available for the preservation of fungi, but the methods can be cumbersome, hazardous, expensive, and often not suitable for long-term storage of non-spore-forming (sterile) fungi. A method of preservation of spore-forming fungi in commercially available porous beads (Micrbank™) under cryogenic condition was successfully tested for three non-spore-forming basidiomycetes genera: Rhizoctonia solani (teleomorph: Thanatephorus cucumeris) (n = 19), Ceratobasidium species (n = 1), and Waitea circinata (n = 3), and a non-spore forming ascomycetes , Sclerotinia sclerotiorum (n = 1). For comparison, spore-forming ascomycetous fungi, Alternaria alternata (n = 1), Bauveria basiana (n = 2), Botrytis cinerea (n = 1), Fusarium oxysporum f.sp. gladiolii (n = 1), Trichoderma spp. (n = 3), and Thielaviopsis basicola (n = 2) were also cryopreserved in Microbank beads. Viable fungal isolates of all test species were retrieved after five years of storage at −80 °C, which was longer than the viabilities of the corresponding isolates cryopreserved in agar plugs or colonized wheat seeds. Fungi revived from the Microbank beads maintained identical morphology and cultural characteristics of the parent isolates. Randomly selected Rhizoctonia isolates revived from the Microbank beads maintained respective pathological properties of the parent isolates; also, no mutation was detected in the internal transcribed spacer (ITS) ribosomal DNA when compared with respective cultures maintained at ambient temperature. This finding demonstrated the utility of cryopreservation in Microbank beads as a convenient alternative to conventional long-term preservation of a wide group of fungal cultures for plant pathological investigations and serves as the first report of using porous beads under cryogenic conditions for long-term storage of sterile fungi.

Isolation and identification of seed mycoflora associated with seeds of four varieties of chilli viz., GVC- 101, GVC-111, GVC-121 and AVNP-C-131 were conducted by standard blotter method and agar plate method. The fungi isolated were Aspergillus niger, A. flavus, Colletotrichum sp., Fusarium sp., Alternaria sp., Penicillium sp., Curvularia sp., M. phaseolina, unidentified sterile fungi with septate mycelium and unidentified sterile fungi with aseptate mycelium. The fungi isolated by standard blotter method were A. niger (1.50-2.00%), A. flavus (1.50-3.00%), Colletotrichum sp. (1.25-2.75%), Fusarium sp. (0.75-2.50%) and Alternaria sp. (0.75%), whereas fungi isolated by agar plate method were A. niger (7.50-14.00%), A. flavus (2.25-4.75%), Colletotrichum sp. (10.50-11.50%), Fusarium sp. (8.50-12.00%), Alternaria sp. (2.00-2.50%), Penicillium sp. (0.75-2.25%), Curvularia sp. (1.00 - 1.75%), M. phaseolina (1.00-1.50%), unidentified sterile fungi with septate mycelium (0.75%) and unidentified sterile fungi with aseptate mycelium (0.75-1.00%). The common and dominant fungi recorded were A. niger (0.00-14.00%), Colletotrichum sp. (1.25-11.50%) and Fusarium sp. (0.00-12.00%). Genotype GVC 101 and GVC 111 were found as most susceptible as maximum number of mycoflora were detected from these varieties. Agar plate method was found more effective as total ten fungal species were isolated by this method as compared to only five fungal species in standard blotter method.

Endophytic fungi are major contributors to fungal diversity and an important component of plant microbiota. Plants growing in biodiversity hotspots and having ethnobotanical utility are often explored for the presence of endophytic fungi with bioactive potential. Western Ghat mountains of India are one of the ten famous biodiversity hotspots in the world. Hence, in the present study, we investigated the diversity of endophytic fungi associated with tissues of Nothapodytes foetida (a tree), Hypericum mysorense (a shrub) and Hypericum japonicum (a herb) collected from forests of Western Ghats with emphasis on diversity of endophytic fungi harbored in different tissues of three plants and their antimicrobial and free radical scavenging activities. A total of 298 isolates belonging to 31 genera were isolated along with dark septate and sterile fungi. All isolates belonged to Dothidiomycetes, Eurotiomycetes and Sordariomycetes of the phylum Ascomycota. Most frequent colonizers were Penicillium, Aspergillus, Fusarium, Gliocladium, Cladosporium, Trichoderma, Colletotrichum, and Pestalotiopsis. Endophytes showed neither any host preference nor any dominance of a single species. Ethyl acetate extracts of 39 endophytic fungi exhibited antimicrobial activity against one or more pathogens, of which the activity of Bionectria ochroleuca NOTL33, Chaetomium globosum HYML55, Alternaria brassicae HYMS01, Aspergillus sp. HYML56 was prominent against most of the pathogens tested. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radicals were effectively quenched by the ethyl acetate extracts of 28 isolates and 34 isolates, respectively. This study is the first of its kind in H. mysorense and H. japonicum, and not only describes the endophytic diversity of these plants but also emphasizes the bioactive potential of endophytic isolates for future use in agricultural, pharmaceutical and industrial applications.

Several common root diseases routinely damage sugar beet in Nebraska and other production areas of the Central High Plains, and it is becoming more common to find fields infested simultaneously with multiple pathogens. Owing to the shortage of available fungicides for economic management of soilborne diseases, alternative techniques such as biological control are increasingly being sought for disease management. Over the last several years, unidentified, sterile fungi have been isolated in conjunction with pathogens from infected sugar beet roots and seedlings. At least two promising isolates have been identified from in vitro assays that inhibit the radial growth of multiple sugar beet root pathogens, including Rhizoctonia solani, Fusarium oxysporum f. sp. betae, Phoma betae and Pythium aphanidermatum. Based on morphological and molecular characterisation, two isolates, ‘Hall’ and ‘R47’, were putatively identified as Rhizoctonia zeae. In vitro pathogenicity testing indicated that these isolates were not pathogens of sugar beet. Both isolates were compared with the well-established biological control fungus Laetisaria arvalis and tested as potential treatments in a field naturally infested with multiple sugar beet root diseases. Data indicated that these fungi provided some level of protection against a complex of soilborne diseases and suggest that these isolates could have a potential fit in an integrative management strategy for several sugar beet root diseases.

Members of the family Chaetomiaceae are ubiquitous ascosporulating fungi commonly, which reside in soil enriched with manure or cellulosic materials. Their role as human pathogens is largely ignored. However, the ability of some species to grow at high temperature enables them to play an important role as opportunistic pathogens. The family contains several genera and species that have never been reported to cause human infection. Hereby, three new species are described; two belong to the genus Subramaniula and one represents a Chaetomium species. Subramaniula asteroides was isolated from various sources including eye and skin infections as well as from the natural environment, and S. obscura was isolated from a toe infection. Chaetomium anamorphosum was isolated from a kidney transplant patient suffering from fungal peritonitis. All species described were previously misidentified as Papulaspora spp. due to the formation of cellular clumps or bulbil-like structures, which are characteristic of Papulaspora. The isolates failed to form sexual fruit bodies and ascospores remained absent, which is an unusual feature for the generally ascosporulating genera Chaetomium and Subramaniula; minute conidia from phialides were sometimes observed.

We isolated filamentous fungi from soil samples of peat layers in Aomori and Oita Prefectures in Japan and Perth and Kinross district in Scotland by a serial dilution plate technique. The mycobiota in each peat soil showed some common and characteristic features. The abundance of fungal isolates (CFU/g) from peat soil was low: about 1/3 to 1/30 compared with evergreen or coniferous forests or cultivated soil. Trichoderma or Mucorales species were scarcely observed; these fungi occupied only 3% of the total number of colonies. On the other hand, fungi such as Conioscypha and Tolypocladium that are normally isolated rather rarely were encountered at a comparatively high rate. Acremonium guillematii and Tolypocladium cylindrosporum were recorded for the first time in Japan. Sterile fungi occupied 50% of the total number of isolates. The low abundance of fast-growing fungi enabled us to pick slow-growing fungi up easily from the isolation medium. It is interesting that species not previously described in Japan, or scarcely reported, were isolated commonly from both Japanese and Scottish samples. A peat soil sample is therefore an attractive source of untapped microbial resources.

An undescribed Microsporum species was isolated from skin scales recovered from a 40-mm large, annular, scaling lesion on the wrist of a 46-year-old woman. The risk factors for dermatophyte infection in the patient were frequent work in the garden, hunting, and contact with dogs and horses. Direct microscopic examination of the scales revealed the presence of dermatophyte hyphae; when the samples were cultured, a morphologically similar fungus grew on all slants in pure culture. Both of these findings strongly suggested that the isolate was the true causal agent of infection. The possible geophilic nature of the species was based on phylogenetic analysis (internal transcribed spacer region of rDNA and β-tubulin gene) that placed it in between species of the M. gypseum complex. However, its divergencies from all other Microsporum species exceeded 4% base pairs. Based on β-tubulin phylogeny, the isolated species is a sister to M. gypseum. The species produces abundant chlamydospores and clumps of hyphae similar to those of ascomatal primordia but no conidia and ascospores. The species was unable to grow at 37 ◦ C and does not grow on T6 basal medium, which is unlike other Microsporum species; hair perforation and urease tests were positive. The addition of histidine to the T6 medium resulted in rapid growth of the fungus. The phylogenetic evidence, morphology, growth parameters, and physiology justified the proposal that the isolate is a new species, M. aenigmaticum, sp. nov.

Muscodor kashayum (MycoBank no.: MB 803800; GenBank no.: KC481680) is a newly described endophytic fungus of a medicinal plant Aegle marmelos (Bael tree), growing in the tropical conserved rainforest in the Western Ghats of India. Muscodor kashayum possesses distinct morphological, molecular and physiological features from the earlier reported Muscodor species. The fungus forms characteristic rings of the ropy mycelium on potato dextrose agar medium. This sterile fungus is characterised by the presence of a pungent smell which is attributable to a blend of more than 23 volatile organic constituents, predominantly 3-cyclohexen-1-ol,1-(1,5-dimethyl-4-hexenyl)-4-methyl; 1,6-dioxacyclododecane-7,12-dione; 2,6-bis(1,1-dimethylethyl)-4-(1-oxopropyl) phenol; 2,4-di-tert-butylthiophenol and 4-octadecylmorpholine. In the in vitro anti-microbial assay using M. kashayum, growth of 75% of test fungi/yeasts and 72% of the test bacteria were completely inhibited. Therefore, M. Kashayum holds potential for future application to be used as a myco-fumigation agent.

The family Trichomeriaceae (Chaetothyriales) mainly comprises epiphytic and epilithic organisms. In some species elaborate ascomata are formed, but for the great majority the species no asexual conidium formation is known other than simple fragmentation of the thallus. The present paper re-establishes the genus Arthrocladium with three non-sporulating species. One of these is described for a strain causing a fatal infection in a human patient with a rare genetic immune disorder.

A 39-year-old farm worker was injured in her right eye by a piece of wire, which resulted in a corneal ulcer unresponsive to antibiotic treatment. The clinical appearance was that of a corneal infiltrate with feathery borders resembling fungal keratitis. Corneal scrapings were collected and the patient was started on natamycin 5% eye drops, fluconazole 0.3% eye drops, and oral fluconazole. A non-sporulating fungus was isolated from the samples. Based upon macroscopic and microscopic morphologic features, it was provisionally identified as a Papulaspora species due to the fact that members of this genus generally do not form diagnostically useful conidia. However, it was found through the use of ITS sequencing that the isolate clustered within the ascomycete genus Chaetomium. The sequence did not fully match with any sequences of available ex-type strains of Chaetomium, Thielavia and Papulaspora and hence might belong to an undescribed specie. However, without diagnostic morphological features the taxon cannot be introduced as a novel member of the genus Chaetomium. Antifungal susceptibility testing was performed according to published standards. The corneal ulcer was successfully treated with six weeks of antifungal therapy.

House dust samples were collected up to six times over a 1-year period to explore seasonal variability of individual fungal genera in inner-city households in Minneapolis, Minnesota. General linear mixed-effects models were used to explore the variability of 13 fungal genera (Cladosporium, yeasts, Aureobasidium, Alternaria, Penicillium, Epicoccum, Mucor, Rhodotorula, Aspergillus, sterile fungi, Phoma, Pithomyces, and Fusarium) found in more than 20% of total dust samples. The five most common fungi (% of samples detected) were Cladosporium (81%), yeasts (63%), Aureobasidium (57%), Alternaria (56%), and Penicillium (55%), with the remaining genera found in 20-50% of the samples. When expressed as frequency of occurrence (%), genus fraction of total fungal concentration (%), or concentration of individual genera (CFU/g), these five genera also varied substantially by season. In contrast, Aureobasidium, Fusarium, and Mucor levels remained relatively constant throughout the year. The observed concentrations of the five most common fungal genera were higher than levels associated with increased respiratory symptoms reported in previous studies. Our results indicate that seasonal variability in common fungal genera is large: within-home to between-home variance ratios of Penicillium (4.1), Alternaria (4.9), Cladosporium (7.1), and yeasts (20.3) were substantially larger than that observed for total fungi (2.5). These results suggest that future studies attempting to link individual fungal genera to health effects need to characterize and control for this seasonal variability.

The potential for mediation of induced systemic resistance (ISR) and the mechanisms used by nonpathogenic beneficial microbes to mediate ISR are currently under intense investigation but have been overlooked in studies examining plant growth promoting fungi (PGPF) or their metabolites. Here, we examined whether culture filtrates (CFs) of three well-characterized PGPF isolates, which demonstrated different responses in hypersensitive reaction-like cell death and β-glucuronidase reporter gene expression of PR-1a and PDF 1.2 constructs, had the ability to induce systemic resistance against the bacterial leaf speck pathogen Pseudomonas syringae pv. tomato DC3000 (Pst) in Arabidopsis thaliana. Arabidopsis plants treated with CFs of Phoma sp. (GS6-2 and GS7-3) and sterile fungus (GU23-3) elicited ISR against the Pst pathogen, resulting in a reduction in the number of symptomatic leaves, restriction of disease severity, and suppression of pathogen proliferation, with the best results obtained with Phoma...

The root-associated fungus LtVB3 was formerly reported as a potential, new biocontrol agent of Verticillium yellows of Chinese cabbage and Fusarium wilt of tomato. According to molecular phylogenetic analysis of the ITS 1-5.8S rDNA-ITS 2 gene regions and morphological characteristics, LtVB3 is here identified as Meliniomyces variabilis, a recently described species [formerly called “Variable White Taxon” (VWT)] in a new genus erected to accommodate sterile fungi with phylogenetic affinities to Rhizoscyphus ericae, an ericoid mycorrhizal fungus. In vitro inoculation experiments showed that LtVB3 colonized the roots of torch azalea and eucalyptus; however, growth was enhanced only in azalea but not in eucalyptus. Hyphae of M. variabilis formed intracellular structures typical of ericoid mycorrhizas in epidermal cells of azalea roots but did not produce any typical ectomycorrhizal structures with or within root cells of either host. In LtVB3-treated eucalyptus roots, some cells in the epidermal and cortical layers had wall appositions and thickenings, which appeared to restrict fungal growth.

Forty six species and two sterile fungi and yeast species were isolated from samples collected both indoors and outdoors of coastal buildings located in an Egyptian coastal city. Twenty flats from ten buildings were investigated; children living in these buildings have been reported to suffer from respiratory illnesses. Samples were taken using a New Brunswick sampler (model STA-101) operating for 3.0 min at a flow rate of 6.0 l/min. Most of the species isolated have been associated with symptoms of respiratory allergies. Indoors the total culturable fungal count was 1548 CFU/m3; outdoors, it was 1452 CFU/m3. Indoor values of culturable fungal count, total spores count and ergosterol content ranged from 52 to 124 CFU/m3, 100 to 400 spore/m3 and 5 to 27.7 mg/m3, respectively, whereas outdoor levels typically varied between 25 and 222 CFU/m3, 110 and 900 spore/m3 and 3.3 and 67.2 mg/m3, respectively. The maxima for these parameters were detected indoors in house no. 6 and outdoors, outside of house no. 7. The most abundant species were primarily mitosporic (2832 CFU/m3). The most frequent species in both the indoor and outdoor samples were Cladosporium cladosporioides followed by Alternaria alternata and Penicillium chrysogenum,with inside:outside ratios of 1.4, 1.8 and 1.9, respectively. The patterns of fungal abundance were influenced to some extent by changes in the relative humidity and temperature. Other factors, such as type of culture media, rate of sedimentation, size, survival rates of spore and species competition,also affected fungal counts and should be taken into consideration during any analysis of bioaerosol data.

Sterile fungi isolated from surface-sterilized roots of the Ericaceae, and hypothesized to be conspecific based primarily on restriction fragment length polymorphisms, were provisionally named as Variable White Taxon (VWT). In preliminary resynthesis trials with Vaccinium myrtilloides or V. vitis-idaea, isolates did not form typical ericoid mycorrhizas. Additional isolates obtained from roots of the Orchidaceae, Pinaceae, Betulaceae and Salicaceae, and given informal names such as Sterile white 1 (SW1), were thought to represent the same taxon based on cultural similarities. To evaluate conspecificity and infer phylogenetic affinities, partial nuclear ribosomal DNA sequences were determined. Parsimony analyses supported a species level distinction for VWT/SW1 and indicated that the fungus is placed within the species complex referred to as the “ Hymenoscyphus ericae aggregate” which includes H. ericae ( Leotiomycetes ), many unnamed taxa and Cadophora finlandica. The new genus and species Meliniomyces variabilis is proposed to accommodate this root-associated fungus to facilitate discussion and information retrieval, and to provide a foundation for additional experimental work. Although isolates are sterile in culture, they can be identified by morphological characters in conjunction with ribosomal internal transcribed spacer (ITS) sequence data. The mycorrhizal status of M. variabilis is not yet clear. In prior published results, strains demonstrated no or some colonization with ericoid and ectomycorrhizal hosts but did not form true ectomycorrhizas. ITS analyses indicated that the “ H. ericae aggregate” includes several other well-supported clades putatively named as Meliniomyces species. Representative strains were examined morphologically for two of these species, described as M. vraolstadiae and M. bicolor. Both include ectomycorrhizal mycobionts of the “ Piceirhiza bicolorata ” morphotype. Rhizoscyphus ericae is accepted as the appropriate name for H. ericae. Taxonomic novelties: Meliniomyces Hambleton & Sigler anam. gen. nov., Meliniomyces variabilis Hambleton & Sigler sp. nov., Meliniomyces bicolor Hambleton & Sigler sp. nov., Meliniomyces vraolstadiae Hambleton & Sigler sp. nov.

The aim of this study was to investigate the relationship between airborne fungal spores and allergic diseases; for this reason, the airborne fungal spores that were obtained from five different locations of Belgrad Forest were isolated, determined and studied quantitatively. Totally 120 samples were examined by using the Petri Plate Gravitational Method, and fungi obtained from these samples were isolated and 600 colonies were counted. By identification of these isolations, 13 genera (Mucor, Rhizopus, Absidia, Aspergillus, Penicillium, Trichoderma, Trichothecium, Stemphylium, Cladosporium, Alternaria, Ulocladium, Aureobasidium and Fusarium), 25 species and 10 different sterile fungi were determined. The identifications of these fungi were made according to their microscopic, macromorphological features and references.

The composition of saprotrophic soil fungi in the mor layerof a Calluna-dominated, Danish heathland wasinvestigated after two years of fertilization with ammoniumnitrate (0, 35, 50 and 70 kg N ha1- yr-1) using asoil washing technique. The most frequently isolated generafrom the soil particles plated were Penicillium, Trichoderma, Mortierella and Mucor. Eightspecies of Penicillium were identified and Penicillium spinulosum was the most frequently isolated.The occurrence of dark, sterile fungi on the soil particleswas low. There were no measurable changes in the specificcomposition of the saprotrophic soil fungal groups due tothe nitrogen treatments, beside from an increasedoccurrence of Absidia californica. I conclude that adirect impact on the composition of the saprotrophic fungiin heathland soil is unlikely under enhanced nitrogen input.

The broad spectrum fungicide mancozeb was applied to monocultured sugarcane soils affected by the growth constraint known as sugarcane yield decline. The constraint is associated with the long-term monoculture of sugarcane and has been shown to decrease sugarcane growth by 20% in commercial crops in Queensland. The fungicide was shown to decrease root colonization by soil fungi, particularly dematiaceous sterile fungi. Higher doses of mancozeb (up to 400 mg kg-1) sometimes led to increased populations of Penicillium spp. The fungicide greatly improved plant growth and root health when applied at doses of 100 mg kg-1 and above. Results suggest that the role of dematiaceous sterile fungi in sugarcane yield decline should be further examined.

The ability of four fungi to suppress nematode reproduction and ameliorate yield loss of white clover (Trifolium repens) in soil infested with clover cyst nematode (Heterodera trifolii) was examined in a pot experiment. Three fungal parasites of nematode eggs (two sterile fungi and Scolecobasidium constrictum) and a parasite of nematodes (Hirsutella rhossiliensis) were added to soil in the form of alginate beads. At eight weeks after sowing, the mean number of cysts which developed per pot was reduced by Scolecobasidium constrictum, one of the sterile fungi and H. rhossiliensis. H. rhossiliensis also reduced the number of cysts per gram of plant dry matter and maintained dry matter yield per pot and per plant at a level not significantly different from that of control pots (without nematodes) or pots treated with H. rhossiliensis alone. The number of eggs which developed within each cyst was increased in the presence of H. rhossiliensis. Results suggest that fungi such as H. rhossiliensis may have the potential to enhance the establishment of white clover.

The occurrence of parasitic and saprophytic microflora on roots of eight winter wheat cultivars was recorded at seven plant experimental stations with different climatic and soil conditions during four plant growth stages. The rates of recovery for pathogenic and sprophytic microorganisms were negatively correlated, and the negative correlations became larger as the crop matured. Similarities were noted between the ratios of pathogen to saprophyte recovery in spring samplings as well as between the root assays in early summer and early autumn. In spring, recovery of pathogenic Fusarium spp. was negatively correlated with recovery of saprophytic Trichoderma spp., and recovery of pathogenic Altemaria spp. with saprophytic spp. of Trichoderma and Epicoccum . In summer and autumn, a negative relationship was found among saprophytic sterile fungi, saprophytic Mucor spp. and pathogenic Fusarium spp. Differences among recovery ratios were found for the various plant breeding stations but not among individual cultivars. The average rates of recovery for pathogenic microorganisms thus depended on planting location and plant growth stage but the recovery ratios did not depend on cultivars. It suggests a stronger influence of these environmental components than cultivars on pathogen recovery rates. Mutual interactions among microflora species, planting conditions, and plant development will strongly influence field resistance to pathogens.

Among 21 rhizosphere fungi tested, eight sterile fungi and oneTrichoderma isolate (GT2-1) from zoysiagrass rhizosphere promoted the overall growth of soybean varieties when grown in the greenhouse. Out of nine effective isolates, GS7-4, GS8-2, GS8-3, GU23-3 (all sterile fungi) and GT2-1 (Trichoderma sp.) promoted plant growth and increased yield of Toyosuzu (variety 1) significantly, while GS8-3, GS10-1, GS10-2 (sterile fungi), and GT2-1 significantly caused plant growth promotion and yield increase of Kitamusume (variety 2). Among these efficient isolates, GS8-3 and GS10-2 induced considerable and consistent increases in length, biomass and yield of plants of varieties 1 and 2, respectively. In the field, however, only GS8-3 and GU23-3 among seven selected isolates, induced consistent and significant increases in plant growth and yield of varieties 1 and 2, while the ability of other isolates decreased. The plant growth promotion by these isolates in the field followed a similar trend to that in the greenhouse, but the effect was less marked. Some isolates which were effective in the greenhouse were less effective in the field. The degree of growth promotion by different isolates depended on the variety of soybean. The nutrient condition of soils used in experiments also seemed to play a vital role, since notable growth promotion by these isolates was observed in nutrient-depleted soil.

Systemic resistance against Colletotrichum orbiculare was induced in cucumber plants by amending potting medium with the barley grain inocula of plant growth promoting fungal (PGPF) isolates obtained from zoysiagrass rhizosphere. Out of 16 isolates tested, 10 protected plants against a spore concentration of 10 4 spores ml −1 of C. orbiculare . However, as the spore concentration of the pathogen was increased, the protection afforded by PGPF isolates decreased. Among those isolates, five protected plants even at a high pathogen spore concentration of 10 6 spores ml −1 . Three, among these five isolates, colonized roots; GS8-3 colonized roots to the maximum extent, while GS8-1 and GS8-2 were moderate and poor colonizers, respectively. These three root colonizers, along with one root non-colonizer (GU21-2), were tested for their induction ability over a period of 9 weeks. All four isolates protected plants but their ability to initiate resistance varied. Root colonization by GS8-1 and GS8-3 correlated with the protection offered. Their failure to induce resistance when provided as autoclaved barley grain inocula suggests that the initiation of resistance was attributed to invasion of roots. The other two isolates, on the other hand, induced systemic resistance to some extent when provided as autoclaved inocula suggesting that thermostable factors might be responsible. The four select isolates enhanced growth by increasing plant height and biomass significantly, which was quite evident after 5 weeks of growth. The plants associated with GS8-1 and GS8-2 were induced to produce a significant increase in the number of fruits. The dual nature of these soil-borne sterile fungi as inducers of resistance and as growth promoters over prolonged durations are discussed.

Little is known about the dynamics of succession of fungi on limestone exposed in subtropical environments. In this study, the colonization of experimental blocks of compact and porous limestone by a fungal community derived from natural biofilms occurring on Structure X from the archaeological site of Becan (Mexico), was studied using a cultivation-dependent approach after short-term (9 m) exposure in order to provide a preliminary insight of the colonization process under seminatural conditions. Microbial growth seen as the change of colour of stone surfaces to black/dark green was more abundant on the porous limestone. There was a fairly clear difference in microbial colonization between the onset of the experiment and the 6th month for both limestone types, but no significant increase in the colonization of coupons occurred between months 6 and 9. This could be related to the low rainfall expected for this period, corresponding to the dry season. A total of 977 isolates were obtained. From these, 138 sterile fungi were unidentified, 380 could only be assigned to the order Sphaeropsidales; the remaining isolates (459) were grouped into 27 genera and 99 different species. Nearly all detected fungal species belonged to the Ascomycota (90 %). Rare taxa (species represented by one to three isolates) included the recently described genus Elasticomyces, several species of genera Hyalodendron, Monodyctis, Papulospora, Curvularia, and Septoria. Other taxa were Minimedusa and Gliomastix luzulae, which have not been previously described for stone environments. Abundant fungi included several species of the common genera Cladosporium, Alternaria, and Taeniolella typical for a range of habitats. Succession of populations was observed for certain taxa, this shift in the composition of fungal communities was more evident in porous limestone. After 6 m of exposure, species of the genera Scolecobasidium, Hyalodendron, and Taeniolella were predominant, while after 9 m, the predominant species belonged to the genera Curvularia and Alternaria, particularly on porous stone. These results suggest that Curvularia and Alternaria replaced other fungi, due to a higher tolerance towards low levels of available water during the dry season. Higher levels of water within the porous stone, keep longer periods of microbial activity, minimizing the impact of desiccation. This study contributes to understand the diversity of fungal communities in stone surfaces in subtropical settings and the dynamics of colonization on limestone.

Eleven out of 18 sterile fungal isolates and an isolate each of Penicillium sp. and Trichoderma sp. from the zoysiagrass rhizosphere were effective in enhancing the growth of two wheat varieties in greenhouse conditions. They enhanced the top length and top dry biomass of plants significantly and induced the plants to produce long earheads and more seeds. Notable among isolates were GS6-1, GS6-2, GS7-3, GS7-4, GS8-6, GS10-1, GS10-2, and GU23-3, which enhanced the growth by several times, resulting in a conspicuous growth promotion effect that differed depending on the variety. Penicillium and Trichoderma species were less effective than sterile isolates in enhancing growth. Seven of the 11 effective sterile isolates from the zoysiagrass rhizosphere (as determined under greenhouse conditions) and a wheat rhizosphere isolate (K-17) were further tested under field conditions. Most of the isolates except K-17 enhanced the growth of one variety, whereas a few isolates enhanced the growth of the other variety. However, at least four isolates each increased yields of both varieties. Isolate GS6-1, which was very effective under greenhouse conditions in promoting overall growth, was less effective under field conditions; however, the yield components were not affected. The efficiency of the plant growth promoting isolates depended upon the wheat variety and soil nutrient conditions in addition to their inherent growth promotion abilities.Key words: plant growth promoting fungi (PGPF), sterile fungi, wheat growth promotion, yield components.

Dark septate endophytes (DSE) are com- mon and abundant root-colonizing fungi in the native tallgrass prairie. To characterize DSE fungi were isolated from roots of mixed tallgrass prairie plant communities. Isolates were grouped according to morphology, and the grouping was refined by ITS- RFLP and/or sequencing of the ITS region. Sporulat- ing species of Periconia, Fusarium, Microdochium and Aspergillus were isolated along with many sterile fungi. Leek resynthesis was used to quickly screen for DSE fungi among the isolates. Periconia macro- spinosa and Microdochium sp. formed typical DSE structures in the roots; Periconia produced melanized intracellular microsclerotia in host root cortex, whereas Microdochium produced abundant melanized inter- and intracellular chlamydospores. To further validate the results of the leek resynthesis growth responses of leek and a dominant prairie grass, Andropogon gerardii, were assessed in a laboratory resynthesis system. Leek growth mainly was unrespon- sive to the inoculation with Periconia or Microdochium, whereas Andropogon tended to respond positively. Select Periconia and Microdochium isolates were tested further for their enzymatic capabilities and for ability to use organic and inorganic nitrogen sources. These fungi tested positive for amylase, cellulase, polyphe- nol oxidases and gelatinase. Periconia isolates used both organic and inorganic nitrogen sources. Our study identified distinct endophytes in a tallgrass prairie ecosystem and indicated that these endo- phytes can use a variety of complex nutrient sources, suggesting facultative biotrophic and saprotrophic

Isolates of 117 dematiaceous and 10 hyaline, septate, sterile fungi were obtained from the roots of 26 plants belonging to Poaceae, Caryophyllaceae, Rosaceae, Ericaceae, Primulaceae, and Asteraceae from a subalpine dwarf shrub heath in the Alberta Rocky Mountains. The isolates were sorted into 33 culture groups based on colonial morphology. Strains representative of the different culture groups were compared with fungi of known identity (Cenococcum geophilum, Hymenoscyphus ericae, Phialocephala dimorphospora, Phialocephala fortinii, Phialophora finlandia) using restriction fragment analysis of an amplified portion of ribosomal DNA. Cluster analysis and ordination based on restriction fragment polymorphisms indicated that two-thirds of the isolates were closely related to or conspecific with Phialocephala fortinii, which therefore appears to represent the dominant root endophyte of the subalpine site. In culture, many of the Phialocephala fortinii isolates had sclerotia composed of compact masses of darkly pigmented and irregularly lobed, thick-walled hyphae. Five of the isolates clustered independently of the known isolates and are probably each representative of species other than the known strains. Key words: subalpine mycorrhizae, Phialocephala fortinii, restriction fragment length polymorphism, ribosomal DNA.

SUMMARY Fungi were isolated from soybean plants in ten fields in south-west France. Correspondence analysis (COA) was used to find associations among taxa (species, genera, groups) and sampling units (i.e. one field at one sampling date). The first axis of the COA demonstrated a dominant sampling date effect; the second indicated an association among certain sampling units and specific taxa. Regression analysis of COA coordinate values indicated that fields with high relative isolation frequencies of Fusarium spp., F. oxysporum and ‘other species’ (mostly Chaetomium spp. and sterile fungi) were characterised by greater plant fresh weight and nodule number and lower ratings for root necrosis. Cylindrocarpon spp., Cephalosporium spp. and F. solanihad high relative isolation frequencies in fields with lower plant weight, lower nodule number and higher root necrosis ratings. The relative importance of fungal taxa was also related to soil type.

Microfungi isolated from soil samples collected in Franz Joseph Land by means of the soil dilution and soil washing methods were screened for their ability to grow at low temperatures. The oligotrophic ability of the psychrotrophic strains was then determined on silica gel. A total of 40 taxa from 21 genera were isolated. Most isolates were species of Acremonium, Geomyces, Mortierella, Phialophora, Phoma, Thelebolus and sterile fungi. Eutypella scoparia, Hyphozyma variabilis and Ovadendron sulphureo-ochraceum are new records as soil and Arctic fungi. Most fungal isolates were psychrotrophic. The few psychrooligotrophs were species of Geomyces, Phoma, Thelebolus and Mortierella. Overall, our results suggest that the major component of an Arctic soil mycoflora should be active in one or more short growing seasons interspersed with periods of prolonged dormancy. Only a minor component, such as the small group of psychrooligotrophic fungi found in this study, may be expected to show continuous slow growth.

A study of the fungal flora of soils, plant leaves, and litter was undertaken on the Truelove Lowland, on the north coast of Devon Island, N.W.T., Canada. A total of 53 taxa from 33 genera were identified, 27 from leaves and litter and 46 from soil, using soil-washing and plating as isolation methods. The predominant fungi on leaves and litter of Carex stans and Dryas integrifolia were sterile fungi, associated with Cladosporiuin, Phoma herbarum. Penicillium spp., and yeasts. Sterile fungi, Penicillium spp. and Chrysosporium pannorum were predominant in raised beach soils, whereas a new species of Cylindrocarpon, sterile fungi. Penicillium, and Aspergillus species predominated in meadow soils. Use of direct observation methods showed that fungal biomass in meadow soils was much higher than in raised beach soils. In raised beach soils fungal biomass was heavily influenced by the distribution of cushion plants. In comparison with other tundra regions, the Truelove Lowland appears to have a moderately rich mycoflora, containing taxa common both in temperate regions and in other tundra soils. Total fungal biomass in Truelove Lowland soils was found to be low in comparison with many tundra regions.

A method was devised to study whole lengths and thin sections of roots of sterile wheat seedlings with the SEM. Roots were infected with six sterile fungi, and the form of their hyphae in pure culture on their natural habitat was recorded and compared with that in agar culture.

Sterile fungi from wheat roots (563 isolates) were assigned to types on the basis of the pigmentation, morphology, nuclear number and branching pattern of their hyphae, growth rates on three agar media, growth under near-ultraviolet (nuv) light, and the presence of chlamydospores or microsclerotia. Four types with dark-pigmented hyphae (D 1–4), three with hyaline hyphae (H1–3), and two assemblages of infrequently occurring fungi (D5 and H4) were distinguished. Incubation on four artificial media under two light regimes, prolonged exposure to nuv light, or incubation in soil, wheat chaff or lignin medium induced spores to form in some isolates. Structures formed in roots were compared with those formed by twenty known species of sporulating fungi isolated from wheat roots. Most fungi in type D1 were assigned to the Gaeumannomyces-Phialophora complex ; those in D 2 to a Rhizoctonia species; some in D5 to Alternaria alternata and Phoma leveillei; some in H4 to Acremonium rutilum and Cylindrocarpon destructans ; those in H1 to a species of Coprinus when incubated in the presence of soil and living wheat roots, and those in H2 to Acremonium rutilum.

Fungal sporocarps of Hydnangium carneum Wallr., Laccaria laccata (Scop. ex Fr.) Berk. ex Br., Scleroderma spp, Hymenogaster spp., Hysterangium spp, Cortinarius spp, etc. were found to be associated with five species of eucalypts Eucalyptus delegatensis R.T. Bak., E. regnans F. Muell., E. nitens Maiden, E.fastigata Deane et Maiden, and E. saligna Sm.) in nurseries or stands in the North Island of New Zealand. A total of 5345 mycorrhizal pieces were plated out in isolation studies. More than 47% of these pieces remained free of fungal outgrowth, 16% yielded dark sterile mycelia, 7% yielded hyaline sterile fungi, 17% produced sporing Fungi Imperfecti, 5.8% were basidiomycetous fungi identified as H. carneum, Scleroderma spp, Paxillus sp. and Hymenogaster albus (Klotzsch) Berk. et Br., and 5.9% were unidentified basidiomycetes. Mycorrhizas were synthesized on eucalypt seedlings by 12 identified basidiomycetes which form sporocarps in eucalypt stands and 12 unidentified basidiomycetes isolated from the mycorrhizas. Under the test conditions two Cortinarius spp and one unidentified basidiomycete did not form mycorrhizas. The results indicate a possible importance of H. carneum as a mycorrhizal fungus of eucalypts in the North Island of New Zealand.

Fungal invasion of roots in perennial ryegrass turf samples taken during Autumn, from 18 sites in New Zealand, was investigated by microscopy and plate culture isolation techniques. The most frequently encountered fungi were Phialophora radicicola Cain and sterile fungi with dark or hyaline mycelium. Other deuteromycetes, particularly Codinaea fertitis Hughes … Kendrick, Fusarium oxysporum Schlecht., Periconia macrospinosa Lefebvre … A.G. Johnson, Penicillium spp., and Trichoderma spp., basidiomycetes, and vesicular-arbuscular mycorrhizal spp., were also common. Two additional sites were sampled over a 7-month period to examine the effects of root age, season, and fungicide treatment. Fungi were not affected by season or fungicide treatment (benomyl or triadimefon plus iprodione), but brown (old) roots were colonised more by fungi than white (young) roots. Fifty of 51 isolates of fungi commonly found in ryegrass roots invaded roots of ryegrass seedlings grown axenica1ly on water agar. Gaeumannomy...

Soni KK, Pyasi A, Verma RK. 2011. Litter decomposing fungi in sal (Shorea robusta) forests of central India. Nusantara Bioscience 3: 136-144. The present study aim on isolation and identification of fungi associated with decomposition of litter of sal forest in central India. Season-wise successional changes in litter mycoflora were determined for four main seasons of the year namely, March-May, June-August, September-November and December-February. Fungi like Aspergillus flavus, A. niger and Rhizopus stolonifer were associated with litter decomposition throughout the year, while Aspergillus fumigatus, Cladosporium cladosporioides, C. oxysporum, Curvularia indica, and C. lunata were recorded in three seasons. Some fungi including ectomycorrhiza forming occur only in the rainy season (June-August) these are Astraeus hygrometricus, Boletus fallax, Calvatia elata, Colletotrichum dematium, Corticium rolfsii, Mycena roseus, Periconia minutissima, Russula emetica, Scleroderma bovista, S. geaster, S. verrucosum, Scopulariopsis alba and four sterile fungi. Fungi like Alternaria citri, Gleocladium virens, Helicosporium phragmitis, and Pithomyces chartarum were rarely recorded only in one season.

Difficulty is 'sometimes experienced in distinguishing between O. graminis and sterile fungi which form "Ophiobolus-like" runner hyphae on cereal roots. However, it is possible that nuclear distribution in mycelium may prove a differential character as different distributions have already been reported for O. graminis (Chambers and Flentje 1967) and a cereal root-attacking strain of Rhizoctonia solani (Flentje, Stretton, and Hawn 1963). This paper, therefore, describes comparisons of nuclear distribution in O. graminis and several other cereal root pathogens including a sterile fungus which formed Ophiobolus-like runner hyphae.

The species of Omphalia which constitute the subject of this paper are now considered (2) to be the cause of decline disease in the date palm, Phoenix dactylifera L. This malady was first detected in 1921 near Indio, California. Since that time the disease has become well distributed (4) throughout the date-growing region of the Indio district, but it is unknown beyond the boundaries of Riverside County. All underground parts of the palm (3) may be attacked by these fungi, but the principal injury results from the destruction of roots. Secondary symptoms (1) appear subsequently and include the premature death of leaves, retardation in the rate of terminal growth, and reduction in the size of leaves and fruitstalks. The fruit from severely affected palms is nearly worthless. Among the micro6rganisms associated with diseased palms were certain white, sterile fungi with clamp connections at the septa. The first of these cultures was isolated in 1931 by L. J. Klotz, who obtained slight evidences of infection from the inoculation of seedling date palms. Little significance was placed on these results at that time. Later work by the author (2) revealed the pathogenic nature of Klotz's culture, together with that of numerous isolates of similar character from other diseased palms. Since no fruiting bodies of these basidiomycetous fungi were found about date palms affected with decline disease, effort was directed toward inducing sporulation artificially. A group of imperfect toadstools developed in the greenhouse on a wooden pot label (FIG. 3, C). A moldy leaf base from a diseased palm had been buried in soil near the base of this marker. Mycelium which