E.B. Gareth Jones

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.

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.

Occurrence of aquatic hyphomycetes on wood submerged in fresh and brackish water

A number of aquatic fungi have been found growing on Pinus sylvestris, Fagus sylvatica and Ocotea rodiaei test blocks submerged for 6 and 12 weeks in fresh, brackish and sea water. Some observations on the ecology of these fungi are made.

Observations on manglicolous fungi from Malaysia

Thirty-two marine fungi (23 Ascomycotina, 8 Deuteromycotina and 1 Basidiomycotina) are reported from drift and intertidal wood collected in a mangrove stand at Sungei Geylang Patah, Malaysia. The most common species were Rosellinia sp., Savoryella paucispora, Halocyphina villosa and Trichocladium achrasporum .

Physiological requirements of two marine phycomycetes, Althornia crouchii and Ostracoblabe implexa

Growth of two marine phycomycetes isolated from diseased oyster shells was investigated. Both fungi were obligately marine and stenohaline, with optimum growth in 2·3–2·5% sodium chloride. Of the minor salts in an artificial sea-water medium, sodium bicarbonate produced the most significant stimulation of growth of Althornia crouchii. Both fungi grew best at 30 °C; there was no growth at 35°. Light inhibited the growth of the fungi. They grew well in natural or artificial sea water supplemented with yeast extract (1 g/l) and peptone (1 g/l). They did not grow if the concentrations of yeast extract and peptone were reduced to 0·02 g/l. A. crouchii produced normal sporangia and zoospores on glycogen, D(+)trehalose or cellobiose. The addition of sodium malate also permitted good growth, but without zoospore production. Ostracoblabe implexa was stimulated by the simultaneous addition of sodium malate, aspartic acid and sodium glutamate. Most other carbohydrates and fatty acids tested either did not support growth or were inhibitory. Inorganic nitrogen sources tested did not support growth of A. crouchii.

Lignicolous marine fungi from Danish sand dunes

The marine fungi colonizing drift wood collected in sand dunes are listed and compared with those which grew on blocks of beech ( Fagus sylvatica L.) and Scots pine ( Pinus sylvestris L.) submerged in the sea at eight test sites. Fungi were isolated from sand by direct plating out onto agar plates, and baiting the sand with strips of balsa wood ( Ochroma lagopus ). Marine ascomycetes were recovered with the wood baiting technique while the plating out procedure favoured the recovery of Fungi Imperfecti. The significance of these observations with respect to the study of the ecology of sand dune fungi is discussed.

Observations on marine algicolous fungi, including the hyphomycete Sigmoidea marina sp.nov.

Sigmoidea marina sp.nov., a marine hyphomycete growing on drift Fucus serratus and Laminaria saccharina , is described and compared with the freshwater hyphomycetes Anguillospora and Condylospora . Ascomycetes, Fungi Imperfecti and thraustochytrids isolated from seaweeds are listed, and Corollospora intermedia is recorded for the first time from British coastal waters.

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.

The effect of salinity on sexual and asexual sporulation of members of the Saprolegniaceae

The effect of salinity on the sexual and asexual reproduction of seventeen saprolegniaceous fungi was investigated. Normal zoospore formation was observed in nine species in 10% sea water, while in five species cleavage occurred but non-motile stages were formed. In 20 % sea water, small sporangia were formed but no cleavage into zoospores occurred with the exception of Saprolegnia parasitica Coker and Thraustotheca clavata Humphrey where some non-motile spores were observed. Sexual reproduction was observed in all species in 10% sea water with the exception of Isoachlya toruloides Kauffman and Coker (no cleavage) and Saprolegnia ferax (Gruith) Thuret and T. clavata (incomplete cleavage). In 20% sea water, only the oospheres of Protoachlya paradoxa Coker matured. The significance of the results in relation to the ecology of the species are discussed.

Marine fungi: II. Ascomycetes and deuteromycetes from submerged wood and drift Spartina

Sporidesmium salinum sp.nov., a marine hyphomycete on wood submerged in the sea is described. The following are recorded, with discussions where necessary: Dictyosporium pelagica (Linder) G. C. Hughes apud Jones; D. toruloides (Corda) Gueegen; Piricauda pelagica Johnson, transferred to Monodktys; M. putredinis (Wallr.) Hughes; Culcitalna achraspora Meyers & Moore; and Humicola alopal-lonella Meyers & Moore. The Ascomycetous species Ceriosporopsis halima Linder, Halosphaeria circumvestita Kohlmeyer, H. torquata Kohlmeyer, Lulworthia fucicola Sutherland, L. medusa (Ell. & Ev.) Cribb & Cribb, L. opaca (Linder) Cribb & Cribb and Sphaerulina orae-maris Linder are recorded and discussed.