Terrestrial Fungi Research Articles

Seasonal Occurrence and Distribution of Fungi Associated with Spartina Alterniflora from a Rhode Island Estuary

The seasonal occurrence and distribution of filamentous fungi on the aerial parts of salt marsh cordgrass, Spartina alterniflora, along a Rhode Island estuary were studied over a 26-mon period. Fungal fruiting bodies were observed on freshly collected standing plants and their frequency varied with the season. Frequency patterns were similar over the two growth-death cycles studied and indicate there may be a characteristic mycota associated with S. alterniflora. The Ascomycetes Buergenerula spartinae and Phaeosphaeria typharum were found to invade early during the growing season and the Deuteromycetes Alternaria alternata, Epicoccum nigrum, and Stagonospora sp. reached their highest frequencies at the time of seed production. Species of Leptosphaeria and Pleospora were found primarily on dead standing culms. A combination of both marine and terrestrial fungi can be observed on S. alterniflora, with the marine species occurring on the lower portion of standing plants. The number of observations of fungal species/plant was the greatest at the time of seed production, senescence, and death (September-January). The mycota at the three sampling stations, which differed in salinity, was similar and, in general, the fungi which occurred at the highest frequencies were found at all the sampling stations.

Fungi and Bacteria Associated with Leaves During Processing in a Woodland Stream

Autumn—shed leaves of white oak (Quercus alba) and pignut hickory (Carya glabra) were fastened together and incubated in a third order hardwater stream in south—western Michigan. At biweekly intervals, leaves were removed and the microbial populations assessed. Direct counts of bacteria increased logarithmically with time, but viable counts were generally lower. Flexibacter, Achromobacter, Flavobacteria, Pseudomonas, and Cytophaga were isolated from leaves. No apparent bacterial succession was detected. The mycoflora was assessed in five ways, including direct examination and incubations ranging from environment simulating to particle platings on nutrient medium. Although this last technique suggested that common soil and litter fungi dominated, direct examination and environment—simulating incubations showed that aquatic hyphomycetes, particularly Alatospora acuminata, Flagellospora curvula, and Tetracladium marchalianum were the dominant members of the mycoflora. The successional pattern of these fungi on both leaf species is discussed. It is concluded that the aquatic hyphomycetes are actively growing and completing their life cycle in this environment and that the terrestrial fungi are normally present mainly in a dormant state, growing and sporulating only in greatly enriched conditions. The highest ATP levels observed corresponded to the periods of highest fungal frequencies .

Possible eucaryotic algae (Bangiophycidae) among early Proterozoic microfossils

Recent data concerning extant planktonic red algae, chrysophytes, and haptophytes suggest possible reallocation of certain previously described middle and late Precambrian microfossils to one or more of these eucaryotic groups. Both binary fission and budding reproductive methods characterize Huroniospora of the Gunflint Iron Formation and Palaeocryptidium of the Bohemian Proterozoic. Their reproduction, morphology, habitat, and wide geographic distribution, as well as phylogenetic interpretations based on morphology, life cycles, and biochemistry of extant algae, suggest possible assignment of the Precambrian fossils to the unicellular red algal Order Porphyridiales (Subclass Bangiophycidae) rather than to the procaryotic blue-green algae or to the terrestrial fungi as recently suggested. Living Porphyridium may show peripheral multiple budding, with the resultant small cells held in the mucilaginous sheath that surrounds the parent cell, suggesting a similar relationship of Eosphaera tyleri Barghoorn and the Type 4 organism of Hofmann and Jackson. Eucapsis ? from the Paradise Creek Formation also might be referable to the Rhodophyta (spore packets of Bangiales) or Chromophyta (colony stage of Haptophyceae or Chrysophyceae) rather than to the blue-green algae. Reassignment of the Gunflint taxa to the red algal Subclass Bangiophycidae would make this the earliest fossil record of this group; preservation of these unicellular organisms is due to the exceptional nature of the enclosing chert. The suggested reassignment also would date the evolution of the eucaryotic cell and of vegetative mitotic cell division by binary fission and budding by at least 1.9 × 10 9 yr B.P., about the time previously hypothesized as representing the final transition from an anoxic to an oxygenic atmosphere. Genetic recombination resulting from sexual reproduction, with nuclear fusion and meiosis, first appeared in red or green algae at some time within the succeeding 1 b.y.

Effect of salinity on the reproduction of terrestrial and marine fungi

The effect of salinity on the sporulation of twenty selected fungi, which included terrestrial (10), fresh-water (2) and marine (8) species, was investigated using a variety of techniques, e.g. growth on agar plates, shake culture, a range of substrates and perfusion chambers. Sporangiospores of terrestrial mucoraceous fungi were produced over the whole range of salinities tested but zygospore production was inhibited at higher salinities. Terrestrial ascomycetes showed limited tolerance to high salinity and this may be affected by the available growth factors present. Marine ascomycetes have a wide tolerance to low-salinity conditions and may be less conditioned by the available substrate. The sporulation of the majority of the fungi imperfecti, irrespective of their ecological origin, exhibited a broad tolerance to highland low-salinity conditions. Exceptions were the appendaged marine hyphomycetes which are intolerant of extreme low-salinity conditions, and the appendaged fresh-water hyphomycetes which were inhibited by high-salinity conditions. In Chaetomium globosum Kunze ex Fr. the effect of salinity on perithecial development depends on when the sea-water concentration is added to the perfusion medium. The significance of these observations in relation to the ecological distribution of aquatic fungi is discussed, and what is meant by the term ‘marine fungi’ briefly considered.

Effect of salinity on spore germination of terrestrial and marine fungi

The combined effect of salinity and temperature on spore germination in 11 terrestrial, freshwater and marine fungi was investigated. Spore germination in the terrestrial fungi decreased with increasing salinities and these inhibitory effects were more marked at low temperatures. The five marine fungi examined exhibited a broad tolerance to both salinity and temperature stresses.

Choline sulfate (ester) in marine higher fungi

Choline sulfate (ester) was isolated from the marine imperfect fungus Zalerion maritimum (Linder) Anastasiou, and was subsequently revealed by comparative thin-layer chromatography in eighteen additional isolates of marine fungi including Z. maritimum and ten species of Ascomycetes. The possible role of choline sulfate in the metabolism of marine fungi is discussed in the light of its demonstrated roles in terrestrial higher fungi. The IR and NMR spectral characteristics of choline sulfate (ester) are reported for the first time.

Sodium chloride tolerance of terrestrial fungi.

A survey was made of the NaCl tolerance of 975 species of terrestrial fungi selected from the major taxonomic classes. The penicillia and aspergilli were notably the most resistant with the majority of their species able to grow in the presence of 20% or more of NaCl. The Basidiomycetes, as a class, were decidedly the least tolerant with over half the species unable to withstand more than 2% NaCl. Uniformity of tolerance by multiple strains of various species suggests that this may provide a useful taxonomic criterion.

Sodium Chloride Tolerance of Terrestrial Fungi

A survey was made of the NaCl tolerance of 975 species of terrestrial fungi selected from the major taxonomic classes. The penicillia and aspergilli were notably the most resistant with the majority of their species able to grow in the presence of 20% or more of NaCl. The Basidiomycetes, as a class, were decidedly the least tolerant with over half the species unable to withstand more than 2% NaCl. Uniformity of tolerance by multiple strains of various species suggests that this may provide a useful taxonomic criterion.

Ecological notes on fungi in Mangrove forests

Lists of all marine and terrestrial fungi described from mangrove plants are compiled and relations between these fungi and mangrove forest plants ( Avicennia, Hibiscus, Pluchea, Rhizophora ) are described. Marine ascomycetes, basidiomycetes and deuteromycetes occur on submerged parts of roots (proproots, pneumatophores), stems and branches. Six of thirty-one species appear to be host specific. Most frequent marine species are Lulworthia sp., Metasphaeria australiensis and ‘ Phoma ’ sp. The majority of the forty-four terrestrial fungi described from mangrove trees are parasites on living leaves. High contents of tannin do not protect mangrove plants from decomposition by marine fungi and wood boring animals (shipworms and isopods). Submerged bark and wood of mangroves are deteriorated by higher marine fungi. Wood destruction is of the ‘soft rot’ type. Fewer kinds of fungi occur on bark than on wood; Mycosphaerella pneumatophorae (in Avicennia ) and Keissleriella blepharospora (in Rhizophora ) are exclusively corticolous. Some fungi develop within calcareous layers of shipworm tubes in mangrove roots or branches. Rhizophora forms adventitious roots above injured and fungus-infested root tips. There is a zonation of fungi and other organisms along vertical roots, stems, or branches of mangrove trees. Submerged parts are inhabited by marine fungi, algae, balanids, worms, shipworms, and gribbles. Several species of fungi are usually found together on the submerged part of one root, but no distinct pattern of vertical distribution among the species is evident. Growth of marine and terrestrial fungi overlaps at the high tide line. Organisms above the water include ascomycetes, deuteromycetes, basidiomycetes, and lichens. Horizontal distribution of fungi in a Hawaiian mangrove swamp along a transect from salt to fresh water is described. Marine fungi are absent in the freshwater part. Thus, host specific K. blepharospora occurs only on Rhizophora plants in salt water. Dispersal and geographical distribution of mangrove fungi are discussed. Knowledge of occurrence of marine fungi in the eastern mangrove is almost absent. Some fungi, chiefly host specific ones, have a limited distribution, while omnivorous species are found in mangroves throughout the tropics and sub-tropics. Most mangrove fungi are warm water species.

Investigation of mycelial growth in some gill fungi under laboratory conditions.

The effect of the composition, consistence and pH of the media was investigated in 57 species (110 strains) of gill fungi of theAgaricaeae family with respect to the influence of cultivation conditions. The results showed that different genera have diverse nutritional requirements. Wort agar, adjusted to pH 5.5 was suitable for most of the fungi investigated. The growth rate of mycelial colonies was also compared, and the effect of the fungi on the cultivation medium and certain manifestations associated with growth, including fructification. A growth coefficient, expressing the relation of the length, height and density of the aerial mycelium after 14 days of cultivation was used to characterize the manner of growth of the different species. The experiments confirmed that most wood-inhabiting species grow rapidly, terrestrial fungi more slowly, and mycorrhizal fungi the slowest. Strains of the same species preserved similar growth characteristics. Microscopic study of the growth of the aerial mycelium revealed clamp connections in the hyphae in 69% of the fungi investigated and secondary spores in 11%.

The effect of salinity on the growth of marine fungi in comparison with non-marine species

The dry weights of ten marine, one fresh-water and two terrestrial species in sea-water media showed that growth of the marine fungi is not markedly affected by variations in salinity and is much less affected than that of the two terrestrial fungi. Dry weights of the same thirteen species and of another four marine and five non-marine in media made up with distilled water and sea water indicated that though the response of the marine fungi varied from species to species, in only one instance was dry weight significantly greater in a distilled water medium. However, the non-marine fungi all produced significantly greater dry weights in this latter medium. The value of results of this kind for the interpretation of the growth of these fungi under natural conditions is discussed.