Terrestrial Fungi Research Articles

Fungi from water, soil and air polluted by the industrial effluents of manquabad superphosphate factory (Assiut, Egypt)

Abstract One hundred and one species and three varieties belonging to 53 genera of zoosporic (25 species and 15 genera) and terrestrial (76 species and 3 varieties and 38 genera) fungi were isolated. The water and submerged mud directly exposed to industrial effluents were the poorest in terrestrial fungi and zoosporic fungi were completely absent. The samples had low pH, low oxygen content and relatively high levels of phosphate, sulphate, calcium and magnesium. Dictyuchus sterile and Aphanomyces laevis were the commonest zoosporic species and Aspergillus fumigatus, A. niger, A. flavus, Alternaria alternata, Gibberella fujikuroi and Stachybotrys chartarum the most prevalent terrestrial fungal species. Tripospermum sp. (aquatic hyphomycetes) was isolated from the phyllosphere of Myriophyllum spicatum and is a new record for Egypt. Some variations in the fungal diversity, frequencies and populations are related to the source of the material and the media used.

Fungi from a Mediterranean Salt-pan

The Faraman pan is a highly saline Mediterranean coastal pool. Few micro-organisms are able to grow in this extreme environment, where the total dissolved salt content averages 300‰ with sodium chloride as one of the main components. Five species of fungi were collected from driftwood, and several Deuteromycetes and two Ascomycetes were found growing on the vegetation around the edges of the pan. These terrestrial fungi are able to develop in culture media with higher salinity levels than those of sea-water

Detecting morphological convergence in true fungi, using 18S rRNA gene sequence data

For the true fungi, phylogenetic relationships inferred from 18S ribosomal DNA sequence data agree with morphology when (1) the fungi exhibit diagnostic morphological characters, (2) the sequence-based phylogenetic groups are statistically supported, and (3) the ribosomal DNA evolves at roughly the same rate in the lineages being compared. 18S ribosomal RNA gene sequence data and biochemical data provide a congruent definition of true fungi. Sequence data support the traditional fungal subdivisions Ascomycotina and Basidiomycotina. In conflict with morphology, some zygomycetes group with chytrid water molds rather than with other terrestrial fungi, possibly owing to unequal rates of nucleotide substitutions among zygomycete lineages. Within the ascomycetes, the taxonomic consequence of simple or reduced morphology has been a proliferation of mutually incongruent classification systems. Sequence data provide plausible resolution of relationships for some cases where reduced morphology has created confusion. For example, phylogenetic trees from rDNA indicate that those morphologically simple ascomycetes classified as yeasts are polyphyletic and that forcible spore discharge was lost convergently from three lineages of ascomycetes producing flask-like fruiting bodies.

Degradation and oligomerization of syringic acid by distinctive ecological groups of fungi

Forty-four terrestrial and aeroaquatic and aquatic fungi, including fifteen species causing white-rot, four species causing brown-rot, and some species causing soft-rot of wood, were tested for their ability to degrade the monomer syringic acid, which is released during decay of angiosperm lignin. None of the white- or brown-rot species caused any detectable degradation of syringic acid under the test conditions; however, six typical white-rot fungi strongly oligomerized syringic acid, both with and without cosubstrate. The main polymerization product was identified as a 1,3-dimethylpyrogallol oligomer by(13)C-NMR. Other minor metabolic products were methylated and hydroxylated derivatives. Oligomerization depended on the presence of 1 or 2 methoxy groups in ortho position to the hydroxy group of the substrate.Among the remaining fungi,Exophiala jeanselmei, Fusarium eumartii, andPaecilomyces variotii completely and rapidly degraded syringic acid (5 g/liter) within 48 to 100 hours. A further seven species were able to degrade syringic acid to some extent when glucose was added. Methylated and demethylated metabolic intermediates were identified by GC/MS.

Mycoflora associated with five species of freshwater leeches

Twenty-two species belonging to 11 genera of zoosporic fungi were collected from 10 freshwater sites and from five species of leeches on sesame and hemp seeds, maize grains and Pinus pollen grains as baits at 22 degrees C. Dictyuchus, Achlya, Pythium, Allomyces and Saprolegnia were the most common genera. The highest population of zoosporic fungi was estimated from Batracobdelloides tricarinata, the lowest from Barbronia assiuti. In addition fifty-three species and 1 variety representing 23 terrestrial fungal genera were identified on glucose (17 genera and 41 species) and cellulose (20 genera and 34 species + 1 variety) Czapek's Dox agar at 28 degrees C. The most common species on the two media were Aspergillus niger, A. fumigatus, A. flavus, Trichoderma harzianum, Gibberella fujikuroi and Penicillium chrysogenum. Some fungi were common only on cellulose agar medium such as Botryotrichum atrogriseum, Chaetomium bostrychodes, Dactylella alaskana and Drechslera halodes. Batracobdelloides tricarinata was the richest with terrestrial fungi whereas Salifa delicata was the poorest. Five leech species, namely Alboglossiphonia polypompholyx, Batracobdelloides tricarinata, Helobdella conifera, Barbronia assiuti and Salifa delicata were used during this investigation.

Fossils as keys to evolution in fungi

Both flagellated and nonflagellated fungi have an extensive fossil record, which is, however, unevenly documented and often difficult to interpret. Recent work on Silurian, Devonian and Carboniferous terrestrial assemblages has provided plausible evidence for all major groups of extant fungi in the Paleozoic. Key events in fungal macroevolution thus probably took place in the early Paleozoic or the late Precambrian, and the likelihood of finding definitive fossil evidence for them is small. The fossil record also provides evidence for morphological conservatism and early establishment of a spectrum of intimate associations between fungi and vascular plants. A model for the origin of terrestrial fungi involving two distinct lines of biotrophs in lichen-like symbioses with algae is proposed.

Aquatic Fungi Recovered from Sewage Effluents (Assiut, Egypt)

Using zoospore capture technique, 361 colonies of aquatic freshwater fungi were recovered from sewage effluents, out of which 341 reached sexual maturity. These colonies were assigned to 21 species which belong to 9 genera. 67 species in addition to 2 varieties of terrestrial fungi which belong to 25 genera were also recovered.

Occurrence of zoosporic and terrestrial fungi in some ponds of Kharga Oases, Egypt

Thirty-nine species belonging to 13 genera of zoosporic fungi were collected from 33 water samples on sesame and hemp seeds as baits at 22 degrees C. Five genera were isolated in high occurrence: Allomyces (2 species), Achlya (9 species), Dictyuchus (4 species), Pythium (5 species) and Saprolegnia (5 species). Aphanomyces (4 species) and Isoachlya (2 species) were of moderate frequencies. The remaining six genera were less frequent: Anisolpidium, Brevilegnia, Calyptralegnia, Leptolegnia, Pythiopsis and Thraustotheca. Sixty-six species and 2 varieties belonging to 34 genera were identified on glucose-(24 genera and 52 species + 1 variety) and cellulose (31 genera and 48 species + 2 varieties) Czapek Dox agar at 28 degrees C. The most common species on the two media were Acremonium strictum, Aspergillus flavus, A. fumigatus, A. niger, Fusarium moniliforme, F. oxysporum, F. solani, Mucor racemosus, Penicillium chrysogenum and P. corylophilum. Some fungi were common only on cellulose agar medium such as Chaetomium globosum, C. spirale and Memnoniella echinata.

Fundamental Studies for Survival of Terrestrial Microorganisms in the Interstellar Environments

In connection with planetary quarantine, we are studying how terrestrial microorganisms can survive in the cosmic environments. If comon terrestrial microorganisms can not survive in the space even for a short period, we can reduce the cost for sterilizing space probes. The interstellar environments has been simulated by using ultra low temperature high vacuum ( 77 K, 10-6 torr ) improved crynostat and ptoton irradiation from Van de Graaff genarator in the Tokyo Institute of Technology. Various species of terrestrial microorganisms, virus, bacteria, actinomycetes, yeast and fungi were tested quantitatively inactivity under simulated space conditions. After exposing a barrage of the protons corresponding to 250 years irradiation in Space, it was shown that spores of Bacillus subtilis and Aspergillus niger and tabaco mosaic virus can survive about 45%. 25% and 82%, respectively. The results are consistent to report by Weber and Greenberg that spore of B. subtiIis survived 10% under simulated conditions after UV irradiation corresponding to 500 years exposure in space. It might be presumed that the survived terrestrial microorganisms come back to mother earth in future as pathogenic mutants by irradiation of cosmic rays.

Microbial degradation of leaf litter in freshwater streams: effect of low pH – abstract

Many freshwater streams are predominantly heterotrophic, the energy source for all trophic levels of the biota being derived from allochthonous plant litter that is degraded by saprotrophic micro-organisms. Leaves falling into streams have most of their soluble constituents leached out within twenty-four hours of submersion. Few of the resident terrestrial saprotrophs survive in the aquatic environment and the leaves are rapidly colonised by freshwater fungi, particularly aquatic hyphomycetes (Chamier & Dixon 1982a; Chamier et al. 1984). These fungi produce all the enzymes required to degrade the structural polysaccharides of leaf cell walls and those of resident terrestrial fungi. Some species can degrade lignified tissue (Chamier & Dixon 1982b; Chamier 1985). Little is known of the enzymic capabilities of freshwater bacteria.

Isolation of gliovictin from the marine deuteromycete Asteromyces cruciatus

(−)Gliovictin, a diketopiperazine isolated from terrestrial fungi of the genera Helminthosporium and Penicillium, has been isolated from culture broths of the marine deuteromycete Astermyces cruciatus.

Cadmium-nickel toxicity interactions towards a bacterium, filamentous fungi, and a cultured mammalian cell line.

The response of the biota to exposure to individual metals may differ from its response to multiple metals, as mixtures of metals may interact antagonistically or synergistically in their resultant toxicity. The present study evaluated the effects of a combination of Cd and Ni on the freshwater bacterium, Aeromonas hydrophila, the terrestrial fungi, Trichodema viride and Aspergillus niger, and the mammalian cell line, BALB/c mouse 3T3 fibroblasts. This particular spectrum of target cells was selected because studies in the literature show a wide variety of possible interactions between Cd and Ni in their combined toxicities towards bacteria cyanobacteria, slime molds, isolated rat hepatocytes, and rats.

Early land plants

After three decades of vigorous research on the Siluro-Devonian floras neither interest nor productivity is slackening. Some newer developments and comments on the two previous papers are listed here to highlight the varied disciplines and approaches that are being brought to bear on Silurian-early Devonian floras. (i) Banks (1981) reported wounds, probably inflicted by chewing microarthropods, in axes of Psilophyton dawsonii repaired by the form ation of a periderm . Unreported evidence indicates wounding and repair stimulated by piercing and sucking activity of other animals. These observations complement the work of Kevan et al. (1975) on arthropods and damage to plants that are found in the Rhynie Chert, and that of Shear et al . (1984) on a new terrestrial fauna from eastern New York. Interest in plant-anim al interrelationships will attract a new group of scholars to the study of Siluro-Devonian plants. Particularly im portant will be the m aceration of large quantities of rock. (ii) Stubblefield & Banks (1983) found oomycetous fungi within cells in the cellularly perm ineralized aerial axes of Psilophyton dawsonii . Rayner (1983) reported apparent fungal bodies in the spines on compression specimens of Sawdonia ornata . These reports supplem ent that by Kevan et al . (1975) on the fungi in the Rhynie Chert. Whether the fungi were parasitic or saprophytic, or were mycorrhizal as suggested by Pirozynski & Malloch (1975), is unclear on the basis of present evidence. Sherwood-Pike & Gray (1985) have isolated hyphae and spores of higher fungi from macerates of mid to late Silurian rocks from Gotland. Other fragments appear to be coprolites of arthropods that include fragments of hyphae. They suggest that fungi and microarthropods may have served as terrestrial decomposers during late Silurian. Pratt et al. (1978) reported septate fungi in earliest Silurian. These introductory works imply a productive future in the study of Siluro-Devonian terrestrial fungi.

SOME ASPECTS OF THE PHYSIOLOGY AND BIOCHEMISTRY OF MARINE FUNGI

Summary1. This review deals with certain aspects of the physiology and biochemistry of marine fungi. Though it is not easy to define what is meant by a marine fungus, the information presented here relates to those species that by consensus can be accepted as being truly marine. The material is in two parts, that relating to the higher fungi (Ascomycotina, Basidiomycotina and Deuteromycotina) and that relating to the lower fungi, particularly those zoosporic fungi that require sodium for growth.2. Higher marine fungi appear to have a similar carbon, nitrogen and vitamin nutrition to their terrestrial counterparts.3. Growth of higher marine fungi can be optimal in 100% sea water, but more frequently optimal growth is at a lower percentage. The percentage giving optimal growth may be determined by the rate of ion uptake required to generate the necessary turgor for growth. The tolerance of the vegetative phase of many terrestrial fungi to salinity appears little different from that of marine fungi. In general, members of the Basidiomycotina are particularly sensitive to salinity, while those of the Ascomycotina and Deuteromycotina are much more tolerant.4. The degree of tolerance to salinity may be dependent upon temperature and whether or not adaptation by the fungus has occurred.5. Maintenance of a suitable internal potassium concentration by a higher marine fungus is important for growth in a saline medium. Calcium appears to be necessary for the retention of potassium and organic solutes within the hyphae.6. It appears that higher marine fungi are able to maintain a ratio of potassium: sodium higher than that of sea water by the presence of a plasma membrane ATPase which may have a higher pH optimum than the equivalent enzyme from terrestrial counterparts.7. Higher fungi produce more glycerol as the salinity of the external medium is increased. Whether or not the compound is involved in osmoregulation has yet to be determined.8. Turgor is thought to be generated in higher marine fungi growing in sea water by organic solutes (predominantly glycerol and arabitol) and by ions, with the latter playing the major role. Though interpretation of the data depends on several assumptions, the high concentrations of sodium that seem likely to be present in hyphae or cells have implications for the activity of enzymes, if they have similar properties to those of higher plants. There is a need for information on the effects of high concentrations of ions on enzymes located in the cytoplasm of higher fungi.9. In spite of some experimental uncertainties, it seems that reproduction and spore germination of higher marine fungi are very much less affected by salinity than are the same processes of terrestrial counterparts.10. The zoosporic marine fungi require sodium for growth. Though the ion is required at high concentration for growth, sodium cannot be replaced by potassium. Evidence indicates that sodium is involved in the transport of solutes across the plasma membrane.11. The carbon and nitrogen requirements for the growth of the zoosporic marine fungi demand further investigation, particularly at the biochemical level. There is evidence that the respiration of these fungi possesses many interesting features.12. Vitamin requirements of the zoosporic marine fungi depend on the isolate under investigation. Vitamin B., does not now seem to be an obligatory requirement. The ability of phospholipids and sterols to stimulate growth requires further investigation.13. Further studies on marine fungi in the laboratory should focus particularly on growth in continuous culture. Physiological and biochemical studies would be helped by more precise guidance from those concerned with the ecology of these fungi.

Fungi and bacteria associated with pine (Pinus kesiya Royle) needles and teak (Tectona grandis L.) leaf litters during processing in a freshwater lake

Pinus kesiya Royle needles and Tectona grandis L. leaves were exposed in a freshwater lake at three stations and at different depths for a period of 600 days using plastic net bags (1 mm pore size). The fungal and bacterial populations associated with the two litters were estimated at periodic intervals. Rapid initial colonization (up to 100 days) and a lowering of populations after 200–300 days, followed by another peak after 400–500 days were noted. Both fungi and bacteria followed almost similar trends of population variation. Litter at the shallow stations harboured more fungi and bacteria. The species composition of fungi varied with time. The possible role of terrestrial fungi in aquatic habitats is discussed.

Wood Decay Inhibition by Tropical Hardwood Extractives and Related Compounds

Wood Decay Inhibition by Tropical Hardwood Extractives and Related Compounds

The Mycostatic Effect of Seawater on Spores of Terrestrial and Marine Higher Fungi

The Mycostatic Effect of Seawater on Spores of Terrestrial and Marine Higher Fungi

Arsenic metabolism in marine bacteria and yeast

Arsenic metabolism was studied for two marine microorganisms, a facultative anaerobic bacterium, Serratia marinorubra, and an obligately aerobic yeast, Rhodotorula rubra. Both were cultivated in media with (74As) arsenate (As V), and the products of arsenate metabolism were determined qualitatively. Both the bacterium and the yeast produced arsenite (AS III) and methylarsonic acid [CH3AsO(OH)2]. In addition to the foregoing, only the yeast produced dimethylarsinic acid (CH3)2AsO(OH) and volatile alkylarsines. In contrast, the bacterium growing anaerobically with cobalamine as a cofactor did not synthesize gaseous forms of arsenic such as methylarsines. Neither organism synthesized arsoniumphospholipids such as those produced by marine phytoplankton or terrestrial fungi. The yeast did not accumulate arsenite, but instead transported some of it into the culture medium and methylated the remainder first to methylarsonic acid and then to dimethylarsinic acid. Finally, the latter compound was methylated further and volatile alkylarsines were formed. In contrast, the bacterium retained all products of arsenate metabolism intracellularly. Both the bacterium and the yeast, therefore, converted relatively toxic arsenate, the most abundant arsenic compound in seawater, to products that were presumably less toxic.

The mycostatic effect of seawater on spores of terrestrial and marine higher fungi : Kirk, P. W. Jr., 1979/80. Botanica mar., 23(4): 233–238

The mycostatic effect of seawater on spores of terrestrial and marine higher fungi : Kirk, P. W. Jr., 1979/80. Botanica mar., 23(4): 233–238

A study of fungus flies (Dipteral Mycetophilidae) in beech woodland

Abstract. 1. A study was made of larval and adult Mycetophilidae in coppiced beech woodland in southern England. Adult mycetophilids were trapped throughout 1968 using sticky traps at ground level. Larvae inhabiting terrestrial fungi were collected from all sporophores from a defined area of the woodland floor between August and October 1968.2. Larval mycetophilids were extracted from only 12.6% of all sporophores collected and from fifteen of thirty‐eight species of fungi present. Some species of fungi were never inhabited by larval mycetophilids while others appeared to be highly attractive to them. Since it was not possible to identify the larvae beyond the level of tribe it was impossible to ascertain host preferences for different species. Peak numbers of larvae occurred at the beginning of September and the beginning of October.3. Adult mycetophilids had two peaks of activity, the first in March and April when the dominant species were Boletina gripha and Phronia basalis and the second in autumn when species of the genus Mycetophila were dominant. Phronia basalis is a species whose larvae inhabit dead wood and the abundance of this species (40% of all adults) probably reflects the amount of rotting wood in this type of habitat. The autumn peak of adult activity was due to species known to inhabit agaric sporophores and came about 1 month after the peak of larval numbers in fungi.4. The adult fauna was rich with 107 species representing about a quarter of the known British fauna. However, only twelve species were trapped in sufficient numbers to allow deductions concerning seasonal activity.5. The results were discussed with respect to the problems of assessing populations of insects inhabiting fungal sporophores and to the previous work on this neglected group.