Soil Microfungi Research Articles

Molecular Identification of a New Species of Absidia (Cunninghamellaceae, Mucorales) Isolated from Soil in Korea

The species within the family Cunninghamellaceae during an investigation of soil microfungi in Korea, in which three strains were isolated from Gangwon, Chungbuk, and Gyeongbuk provinces, designated as KNUF-22-121A, KNUF-22-126A, and KNUF-22-316, respectively. Because the morphological and molecular analyses of these three strains were identical, KNUF-22-316 underwent further detailed study. Phylogenetic analyses based on the concatenated nucleotide sequences of the internal transcribed spacer region and the large subunit 28S rRNA gene revealed that the strain belonged to the genus Absidia, but occupied a distinct phylogenetic position. The strain KNUF-22-316 was compared with closely related species Absidia radiata CGMCC 3.16257T and Absidia yunnanensis CGMCC 3.16259T, morphologically different with shorter sporangiophores, smaller sporangia and columellae, and the consistent presence of collars. Here, we provide a detailed description and images of this proposed new species, which we have named Absidia microsporangia sp. nov.

Geographical Diversity of Proteomic Responses to Cold Stress in the Fungal Genus Pseudogymnoascus

In understanding stress response mechanisms in fungi, cold stress has received less attention than heat stress. However, cold stress has shown its importance in various research fields. The following study examined the cold stress response of six Pseudogymnoascus spp. isolated from various biogeographical regions through a proteomic approach. In total, 2541 proteins were identified with high confidence. Gene Ontology enrichment analysis showed diversity in the cold stress response pathways for all six Pseudogymnoascus spp. isolates, with metabolic and translation-related processes being prominent in most isolates. 25.6% of the proteins with an increase in relative abundance were increased by more than 3.0-fold. There was no link between the geographical origin of the isolates and the cold stress response of Pseudogymnoascus spp. However, one Antarctic isolate, sp3, showed a distinctive cold stress response profile involving increased flavin/riboflavin biosynthesis and methane metabolism. This Antarctic isolate (sp3) was also the only one that showed decreased phospholipid metabolism in cold stress conditions. This work will improve our understanding of the mechanisms of cold stress response and adaptation in psychrotolerant soil microfungi, with specific attention to the fungal genus Pseudogymnoascus.

Zonal Patterns of Changes in the Taxonomic Composition of Culturable Microfungi Isolated from Permafrost Peatlands of the European Northeast

This paper provides the results of a study on fungal species diversity in the active and permafrost layers of peatlands within frozen peatbogs in the flatland areas of the cryolitozone, European Northeast of Russia (forest-tundra zone, southern and northern tundra subzones). Fungal taxonomic list includes eighty-three species from seventeen genera and two forms of Mycelia sterilia. The phylum Mucoromycota is represented by fifteen species (18% of total isolate number), and these species exhibit the following distribution by genus: Mucor (four), Mortierella (seven), Umbelopsis (three), Podila (one). Ascomycota is represented by sixty-eight species from thirteen genera. The genus Penicillium dominates the species saturation (thirty-seven species, 44%). Soil microfungal complex is represented by rare species (51%), random species (32%), frequent species (15%), and dominant species (2%). In peat soils, dominant species are Penicillium canescens (72%) and non-pigmented (albino) Mycelia sterilia (61%); abundant species are Talaromyces funiculosus (41%), Pseudogymnoascus pannorum (36%), albino Mycelia sterilia (29%), Umbelopsis vinacea (25%), Mortierella alpina (17%), Penicillium decumbens (21%), P. spinulosum (20%), and P. canescens (17%). In active layers of peat soils, abundant species are Penicillium thomii (14%), Mycelia sterilia (13%), Penicillium spinulosum (13%), Penicillium simplicissimum (13%) in forest-tundra; Talaromyces funiculosus (21%), albino Mycelia sterilia (15%), Umbelopsis vinacea (14%) in southern tundra; Penicillium decumbens (23%), P. canescens (17%), P. thomii (13%) in northern tundra. In permafrost peat layers, abundant species are Penicillium spinulosum (17%), Talaromyces funiculosus (34%), and Umbelopsis vinacea (15%) in forest-tundra; Pseudogymnoascus pannorum (30%) and Mortierella alpina (28%) in southern tundra; Pseudogymnoascus pannorum (80%) in northern tundra.

Soil Microbiome in the Impact Zone of the Pechenganikel Plant Emissions (Murmansk Region)

The microbial parameters in Albic Podzol soil were analyzed along the pollution gradient (3, 16, 30, 50 km) with Pechenganickel plant emissions (Murmansk region). The amount and structure of the prokaryotes and fungi biomass were assessed by the method of luminescent microscopy; the content of microorganism’s ribosomal genes copies was determined by real-time PCR; the taxonomic diversity and abundance of culturable soil microfungi were studied. An increase in the number of genes copies of bacteria, archaea, and fungi close the source of emissions compared to remote areas was revealed. In all plots, the highest number of ribosomal genes copies was found for bacteria (from 3.21 × 1010 to 12 × 1010 per g of soil). For fungi and archaea, the number varied from 0.53 × 1010 to 1.59 × 1010 per g of soil and from 0.55 × 1010 to 11.41 × 1010 gene copies/g of soil, respectively. A significant increase in the actinomycetes biomass close the plant was noted, while the biomass of bacteria and fungi remained practically unchanged at different distances from the emission source. Mycelium and fungal spores in all areas are mainly represented by small forms with a diameter of 2–3 microns. The length of the fungal mycelium varied from 51.2 m/g near the plant to 397 m/g in remote areas, with no regularities in its distribution along the contamination gradient. A decrease in the diversity of soil microfungi at the level of genera and higher taxa along the pollution gradient with plant emissions was noted. A change in the structure of communities from polydominant (background site) to monodominant (near the plant) was revealed. The species Penicillium raistrickii dominated in all plots. Fungi Trichoderma viride, dark-colored yeasts Torula lucifuga (3 km) and Aureobasidium pullulans (16 km) also dominated in the zone 16 km from the emission source. In the background area, representatives of the orders Mucorales and Umbelopsidales were dominant.

Temperature and pH Profiling of Extracellular Amylase from Antarctic and Arctic Soil Microfungi

While diversity studies and screening for enzyme activities are important elements of understanding fungal roles in the soil ecosystem, extracting and purifying the target enzyme from the fungal cellular system is also required to characterize the enzyme. This is, in particular, necessary before developing the enzyme for industrial-scale production. In the present study, partially purified α-amylase was obtained from strains of Pseudogymnoascus sp. obtained from Antarctic and Arctic locations. Partially purified α-amylases from these polar fungi exhibited very similar characteristics, including being active at 15 °C, although having a small difference in optimum pH. Both fungal taxa are good candidates for the potential application of cold-active enzymes in biotechnological industries, and further purification and characterization steps are now required. The α-amylases from polar fungi are attractive in terms of industrial development because they are active at lower temperatures and acidic pH, thus potentially creating energy and cost savings. Furthermore, they prevent the production of maltulose, which is an undesirable by-product often formed under alkaline conditions. Psychrophilic amylases from the polar Pseudogymnoascus sp. investigated in the present study could provide a valuable future contribution to biotechnological applications.

Molecular and Morphological Characterization of Two Novel Species from Soil and Beetles (Dorcus titanus castanicolor) in Korea

Two fungal strains belonging to Ascomycota were discovered in Gyeonggi-do, Korea, during this investigation of soil microfungi and microbiota of insects. The strain KNUF-20-047 produced milky white on the back and a milky creamy center to white toward the margin on the front side of colonies. Conversely, the closest Xenoacremonium falcatus displayed a pale luteous to luteous center, white toward margins on the front side, and pale luteous or luteous pigment on the back side, whereas X. recifei produced white colonies. The conidiophores of KNUF-20-047 were slightly larger than those of X. falcatus, and the conidia were distinct from X. recifei. Strain KNUF-20-NI-005 produced light brown to subhyaline conidiophores up to 56.0 μm tall, whereas Rhinocladiella anceps displayed golden to dark brown conidiophores up to 350 μm. Strain KNUF-20-NI-005 also produced larger conidia than R. anceps but smaller than R. coryli and R. fasciculata. Moreover, the molecular phylogeny strongly supports the detailed description and illustration of each proposed species to be designated as Xenoacremonium minutisporum sp. nov. and Rhinocladiella terrigenum sp. nov. in Korea.

Taxonomic Documentation and Statistical Analysis of Soil Mycoflora of Sanjay Gandhi National Park, Maharashtra, India

Aims: The present paper deals with documentation of diversity and analysis of ecological aspects of soil microfungal flora of Sanjay Gandhi National Park (SGNP).
 Study Design: The study area was divided into five zones, defined over span of three ranges and 10% peripheral area.
 Place and Duration of Study: SGNP, Maharashtra, India between September 2016 and September 2020.
 Methodology: A total of 43 soil samples were collected from 5 zones. Microscopic and molecular methods were used for identification of species. We examine dissimilarity in species composition by pairwise Jaccard Dissimilarity Index. We examine diversity of microfungi using diversity indices of Gini-Simpson’s and Shannon’s, true diversity (Shannon’s effective number of species) and equitability of species with Pielou’s evenness index.
 Results: The study resulted in a total of 77 isolates of 77 soil fungi obtained from 43 soil samples. A total of 36 species were documented under 15 genera. Aspergillus was dominant genus with 16 species, whereas Aspergillus niger was dominant species representing maximum 12 isolates. Pairwise Jaccard Dissimilarity Index was found to be above 66% in all cases, with only one species common in all the zones. In diversity indices, Gini-Simpson’s was 0.9347, and Shannon’s, was 3.1450. Pielou’s evenness index was 0.8776, causing true diversity, calculated as effective number of species (23), to be less than observed species richness (36).
 Conclusion: Thus, based on systematics and statistical analysis, it can be concluded that SGNP exhibits rich diversity of soil microfungi.

Microclimatic, climatic, and anthropogenic factors strongly affect cultivable soil microfungal communities at a canyon in the Mediterranean region

In this study, we focused on the effects of microclimatic, climatic, and anthropogenic factors on culturable microfungal communities in the soil of the north-facing slope (NFS) and the south-facing slope (SFS) at the Metzar “Evolution Canyon” in the Golan Heights, Israel. Using the soil dilution plate method, 94 species from 47 genera were isolated. The communities’ composition was subjected to pronounced interslope variations in both summer and winter. Whereas xerotolerant melanin-containing species and thermotolerant Aspergillus spp. predominated in the SFS soil, peaking in the summer, mesophilic Penicillium spp. were especially abundant in the NFS soil. The quantitative parameter—density of microfungal isolates—exhibited the strongest seasonal variations, showing that it was the most sensitive to the fluctuation in soil temperature and moisture. Comparison of microfungal communities in the currently recovered and previously disturbed SFS soil showed that intensive pasturage followed by soil degradation led to the simplification of communities, decreased their diversity level, and resulted in the prevalence of species with different ecological preferences. Comparison of the native NFS communities isolated in the summers of 2002 and 2019 revealed changes in the community structure, which could be related to global warming. These changes were associated with stress-tolerant fungal traits, which may be useful under increasing soil temperature and desiccation.

Soil microorganisms in the urban ecosystems of the russian subarctic (Murmansk region, Apatity)

A comprehensive study of the quantitative and qualitative parameters of soil microfungi, bacteria and algae communities in the Apatity city, located in the subarctic zone of Russia, was carried out for the first time. Urban soil samples were taken from various landuse zones (residential, recreational) and compared to arable and forest soils. In the residential zone, a decrease in the number of microfungi in the topsoil horizon to 1.1 thous. CFU/g compared to 22.7 thous. CFU/g in forest soil was revealed. In the residential zone, an increase was found in the number of saprotrophic bacteria to 7.8 million cells g-1 and oligotrophic to 10.9 million cells g-1 compared to 2.6 million cells g-1 and 1.8 million cells g-1 respectively in forest soils. In the recreational zone, the number of soil microorganisms was similar to that in the forest. A decrease in the species diversity of microfungi in the soil of the residential zone and an increase in the diversity of soil algae were revealed. Among the dominant species of fungi in urban soils, atypical species, including pathogenic ones for humans (Penicillium dierckxii, Stachybotris echinatus, Fusarium sp.), were found. In the algal community, diatoms, yellow-green algae, and cyanobacteria appeared in urban soils in comparison with forest soil. As a result of changes in the quantitative and qualitative indicators of soil microbial communities, a decrease in the enzymatic activity of soils has been noted. This may indicate a weakening of the ecosystem functions of urban soils and an increase in the degree of toxicity for living organisms and humans.

Record on dominant microfungi and their potential phosphate solubilization in tea garden soils

Microfungi are one of the important microbial groups in agriculture due to their positive, mutualistic and negative effect on plant growth and productivity. The roles of fungi extend from organic matter decomposition and mineral cycling to plant growth promotion. Considering these indispensable roles of this microbial group, the present research was undertaken to investigate the indigenous dominant microfungi in tea garden soils of Mokokchung district, Nagaland in India. The dominant microfungi were screened for their phosphate solubilization activity in PVK agar medium using tri-calcium phosphate as the sole phosphate source. Microfungal isolates showed significant differences in culture plates as well as microscopic studies. A total of 110 fungal isolates under 19 genera were identified in the present study. Among the soil microfungi, Aspergillus, Penicillium and Trichoderma were found to dominate the studied tea garden soils. The highest phosphate solubilization activities were observed for species under Aspergillus (1.95 cm to 1.71 cm) followed by Penicillium (1.57 cm to 1.18 cm) and Trichoderma species (1.13 cm to1.06 cm). The present study offers a glimpse of indigenous microfungi as well as provide information on the dominant microfungi in tea garden soils of Mokokchung district, Nagaland and hence, will aid and expand knowledge on indigenous fungi and their various roles. Also, the applications of potent phosphate-solubilizers isolated in this study can be a future source of biofertilizers consortium for tea and other plants.

Molecular Identification and Phylogenetic Study of a Novel Pravastatin-producing Fungal Strain

Pravastatin is a cholesterol-lowering agent of high therapeutic value which is obtained based on a twostep production process. The development of one-step fermentation process based on pravastatin-producing microfungi could be advantageous. We isolated a number of soil microfungi and screened them for pravastatin production. Among them, the isolate ESF21 was selected as an active pravastatin producer. The aim of the present study was to identify this isolate to species level and to investigate pravastatin accumulation by this microfungus. As a result, a range of standard macro- and micro-morphological characters of the ESF21 strain was documented. The isolate ESF21 was a member of the genus Penicillium. Based on the results of molecular characterization, the isolated culture was identified as Penicillium brefeldianum ESF21. To analyze the phylogenetic relationships between this microfungus and other Penicillium species, a phylogenic tree was constructed. When the time course of pravastatin production by the identified strain was investigated, the maximum level of pravastatin (196.83 mg/L) was accumulated after 10 days of fermentation. The identified strain has a scientific interest as a previously unknown wild-type fungal producer of pravastatin.

Microclimatic Gradient as a Source of Variations in Cultivable soil Microfungal Communities at the Negev Desert, Israel

We studied the effect of microclimatic gradient on the spatial (8 habitats) and seasonal (autumn, winter, and summer) variations of culturable soil microfungal communities at the north-facing slope (NFS) and the south-facing slope (SFS) of Nahal Boker, the Central Negev Desert, Israel. Using the soil dilution plate method, a total of 122 species from 56 genera was isolated. The communities' composition was subjected to pronounced interslope variations in each season. While xerotolerant melanin-containing species (mainly with the protective multicellular spore morphology) predominated in the soil of NFS, peaking up in the summer, thermotolerant and thermophilic Aspergillus spp. were especially abundant at the SFS. Aspergilli also dominated the thermotolerant communities isolated at 37 °C from both slopes. The more severe microclimatic regime at the SFS resulted in the least pronounced spatial and seasonal intraslope variability of the community composition as compared to the more benign and heterogeneous NFS. The quantitative parameter—the density of microfungal isolates, exhibited significant and positive relationship with organic matter and moisture content. In seasonal dynamics, the severe summer conditions significantly reduced the differences in isolate density at the NFS, which were markedly expressed in the autumn and winter between habitats receiving additional water by runoff and the adjacent habitats that did not benefit from runoff water.

Litter Fall, Leaf Litter Decomposition, Soil Microfungi and Nutrient Content in Cocoa and Food Crop Agroforest Farmlands in Southeastern Ghana

This study is a comparison of the litterfall, litter decomposition and soil microfungi species diversity in cocoa and mixed food crop agroforest farmlands. The study was carried out in the Atewa and Fanteakwa districts of the Eastern region of Ghana. A total of thirty six sampled plots size of five 25 m x 25 m were randomly demarcated in cocoa agroforest, mixed food crop agrorest and the natural forest reserve. Data collected on litterfall mass and leaf litter decomposition at monthly intervals for a period five months. Soil microfungi species diversity was analyzed from soil samples collected at two depths 0-5cm and 0-10 cm respectively using pour plate method. The reduction in mass of cocoa leaf litter was significantly negatively correlated with the number of days of decomposition. The rate of release of NPK was positively correlated with litter mass. Litter mass production significantly declined in the cocoa agroforest and mixed food crop agroforest farmlands. Initial rate of litter decomposition was generally slow in the cocoa and mixed food crop farmlands than in the natural forest. Soil microfungi species diversity was high in natural forest and low in the cocoa and mixed food crop agroforest farmlands.

Rhizospheric Soil Microfungal Diversity under Hippophae salicifolia D.Don ecosystems of Garhwal Himalayas

The present communication attempts to provide information on the distribution and diversity of rhizospheric soil mycoflora under Hippophae salicifolia D.Don of Garhwal Himalayas. To achieve the target, soil samples were collected from two different localities, viz., Mana of Chamoli and Yamnotri of Uttarkashi districts of Garhwal Himalaya. Samples were also analysed for physicochemical properties, including texture, soil reaction (pH), and organic carbon. The serial dilution method was used to isolate the soil mycoflora. During the investigation, pH ranged from 5.95±1 to 6.67±1, and the moisture content was between 3.86±1 % and 1.63±1 %. Thirty-four species of microfungi belonging to 21 genera were isolated from all the sampling sites. Cladosporium was the most dominant genus, followed by Aspergillus and Fusarium. Cladosporium cladosporiodes was the most common fungi isolated from Hippophae growing sites with maximum contribution (7.43%) whereas, Nigrospora sphaerica was the least important species with minimum contribution ( 0.80%). The highest number of species (23) was isolated from the Mana site of Chamoli District of Garhwal Himalaya. Of the 34 species recorded, six were common, ten frequent, 12 moderate, and six rare occurrences. Similarity ranged from 16.21% to 96.26%. The Shannon-Wiener's diversity index was highest in Mana 2 (2.972), followed by Yamnotri 1 (2.217). Total richness and abundance were the highest in Mana 2 whereas lowest in Yamnotri 1. Evenness was highest in Mana 1 (0.966), followed by Mana 3 (0.954), while lowest observed in Yamnotri 3 (0.905). It was noteworthy in the present contribution that all the soil microfungi reported under H. salicifolia associated rhizospheric soils are new reports to such ecosystems of Garhwal Himalaya. Thus, it is hoped that further investigation of soils under different vegetation regimes of these altitudinal zones mainly dominated by Cedrus deodara, Pinus wallichiana, Picea smithiana, Betula utilis, Alnus nepalensis, Abies pindrow will definitely add to the knowledge of microfungal flora adapted to different ecosystems.

An updated checklist of the myxomycetes in the Maltese islands – An overview of an ongoing research

Myxomycetes are minuscule cryptogamic saprotrophs of decaying vegetative matter, but which also feed and therefore control soil bacteria, microfungi or fungal spores. Yet, their role is not much valued in conservation protocols, and they are not frequently included in red lists. Their study in the Maltese Islands commenced only in the late 20th century by Michael Briffa, where he published 74 records. This account amalgamates the previously published records, revised to their current taxonomy and classification, with new records collected in this research between 2014-2020. The resulting checklist of 96 myxomycetes occurring in the Maltese Islands is here provided. The location, date and host of the first record of each species are given in this annotated checklist. The 22 new records are members of the genera Cribraria, Lycogala, Echinostelium, Perichaena, Trichia, Badhamia, Craterium, Fuligo, Physarum, Diderma, Didymium and Mucilago. This ongoing study on the slime moulds of the Maltese Islands aims to collect, photograph and identify as many specimens as possible so a better represented and updated inventory is compiled. From the past records, experience and fieldwork gained in this research, the myxomycetes that are considered rare or threatened are identified for possible inclusion in a national Red Data List of cryptogams. Moreover, collections currently deposited at the author’s Fungarium may be used to revive populations (e.g. in moist chambers) that are very rare and hence may be used for the conservation of native slime moulds. Finally, this work helps further students and international experts to comprehend which myxomycetes are currently recorded in the Maltese Islands.

Morphology and Phylogeny of Two Novel Species within the Class Dothideomycetes Collected from Soil in Korea

Two fungal strains (KNU-JJ-1827 and KNU-JJ-1829) belonging to the class Dothideomycetes were discovered from Jeju Island, Korea during this investigation of soil microfungi. Strain KNU-JJ-1827 showed fewer conidial septations, larger conidiogenous cells, and smaller conidia compared to the previously identified closest species of Didymocyrtis. Strain KNU-JJ-1829 revealed the similar characteristics of the nearest certain species of the genus Parathyridaria with the production of conidiogenous cells and conidia, because no asexual morphs were detected from the closest type strain Parathyridaria rosae. The novelty of the strains was also confirmed by analyzing molecular data using internal transcribed spacer regions and 28S rDNA. The molecular phylogeny also strongly support the detailed description and illustration for each proposed species as Didymocyrtis septata sp. nov. (KNU-JJ-1827) and Parathyridaria ellipsoidea sp. nov. (KNU-JJ-1829) isolated from soil in Korea.

Soil Microfungi of the Colombian Natural Regions.

Although Colombia was one of the first tropical countries where an effort was made to gather mycological flora, contributions to the taxonomy, diversity, and ecology of soil microfungi are still scarce. In this study, the diversity of soil microfungi was studied collecting data from literature according to the Colombian natural regions: Andean, Amazonian, Caribbean, Orinoquía, Pacific, and Insular. The majority of the records comes from the Andean region, the most accessible to research. The other regions have been much less studied, with the Insular one with no data at all. International literature reported, up to now, ca. 300 different species of soil microfungi belonging to 126 different genera and 6 phyla (Ascomycota, Basidiomycota Mucoromycota, Glomeromycota, Mortierellomycota, and Olpidiomycota). Vescicular-Arbuscular fungi were widely investigated with Acaulospora and Glomus, the most recorded genera with ca. 20 species each. Ascomycota was the most diverse phylum with Penicillium, Aspergillus, and Fusarium representing the majority. Mortierella is strongly present in Mortierellomycota, and in the panorama of all recorded fungi, too. The other phyla and genera were less recorded. It is, therefore, evident the need to continue studying the soil microfungi in Colombia to have a better understanding of soil functioning and its ecosystem services.

Diversity of soil culturable fungi in the tropical montane cloud forest of Veracruz, Mexico

Background: Cloud forest is one of the most threatened ecosystems in the world and more than half of its original area has been transformed for other land uses. Consequently, macro- and microorganisms of this ecosystem have likely undergone changes.
 Objective: To analyze the diversity of saprobic filamentous soil cultured fungi in four cloud forest fragments and evaluate the similarity in species composition among fragments.
 Methods: To detect and isolate soil microfungi, the soil particle filtration technique was used. Emerging colonies were transferred to a culture medium for subsequent quantification and identification. For each species, permanent and semi-permanent slide preparations were made, and taxonomic identification was performed based on morphological features.
 Results and conclusions: From 20 soil samples and 2000 inoculated particles, 233 species were distinguished. The most common species were Myrmecridium schulzeri, Pestalotiopsis maculans, Trichoderma atroviride, Virgaria nigra, Trichoderma cremeum, Fusarium solani, Cordana terrestris, Aspergillus fischeri, and Penicillium olsoni. The most abundant species were Talaromyces flavus and Pestalotiopsis maculans. All the forest fragments had a high richness, diversity, and evenness in addition to a high turnover and high number of exclusive species.

Determination of the Mycelium and Antigens of a Number of Micromycetes in Soil Extracts via Enzyme-Linked Immunosorbent Assay

Sixteen variants of test systems (two-site sandwich and competitive enzyme-linked immunosorbent assay (ELISA)) were studied to determine the concentration of microfungi, some of which are known opportunistic pathogens for humans, in soil extracts. The correlation of the amount of fungal biomass (the length of the growing mycelium) with the concentrations of antigens detected by the two-site sandwich ELISA method and the competitive ELISA method was evaluated. It has been shown that the methods are highly effective in the case of long incubation (more than 5 days) of soil samples and are ineffective for short-term incubation, because there was no correlation between hypha length and antigen concentration during the first day of cultivation. The perspectivity of ELISA methods for the detection of some soil microfungi from genera Aspergillus (Asp. flavus, Asp. fumigatus, Asp. niger), Fusarium (F. solani, F. poae), and others (Alternaria alternata, Phoma lingham, Mucor hiemalis) was shown. The competitive ELISA method was more efficient than two-site sandwich ELISA.

The plant growth-promoting potential of the mesophilic wood-rot mushroom Pleurotus pulmonarius.

To demonstrate the plant growth-promoting potential of a wood-decay mushroom. A wild strain of a white rot fungus (Pleurotus pulmonarius) was found to convert 10mmoll-1 L-tryptophan (TRP) to approximately 15μgml-1 indole-3-acetic acid (IAA) under the optimal growth conditions of 30°C and pH 5 for 15days. Results of gas chromatography-mass spectrometry indicated IAA synthesis through the indole-3-pyruvic acid pathway when using cellulose as a sole carbon source. The mycelium as well as the culture filtrate promoted the growth and chlorophyll content of seedlings. In a monocotyledonous plant (rice), the number of lateral roots was increased experimentally, whereas in a dicotyledonous plant (tomato), the fungus led to an increased length of shoots and roots. TRP-dependent IAA production was demonstrated for the first time for P. pulmonarius and may be responsible for enhancing plant growth in vitro. Synthesis of IAA as the most prevalent phytohormone in plants has been demonstrated for soil microfungi. Pleurotus pulmonarius is reported as an IAA-producing wood-decay macrofungus. The higher temperature optimum of P. pulmonarius isolated from subtropical environment compared to other Pleurotus species from temperate regions makes it more suitable for application in subtropical/tropical regions.