中国江西爱氏霉属三个新种

对江西省植物凋落物上的暗色丝孢真菌进行了调查研究,自植物枯枝上发现爱氏霉属3个新种——江西爱氏霉、井冈山爱氏霉和庐山爱氏霉,根据采集材料对其进行了详细的形态描述和显微拍照。爱氏霉属迄今已报道69个种。该属广布全球,多数种腐生于植物凋落物或沉水腐木上,未见作为植物病原菌引起植物病害的报道。     

Comparative ecology of Gammarus pulex (L.) and Asellus aquaticus (L.) II: fungal preferences

This paper continues to explore niche differentiation in Gammarus pulex and Asellus aquaticus by analysis of their food preferences. Individuals from both species discriminated between leaf discs colonized by different fungal species and exhibited strong preferences for Anguillospora longissima and Heliscus lugdunensis. Fungal preferences were not correlated with the relative abundance of fungi in the field and there was considerable intra-population variability in food preferences — both between individuals and for the same individual through time. Niche overlap between animals from all four study populations was high and there was no evidence of differences in the potential trophic niches of animals from sympatric and allopatric populations.     

<Emphasis Type="Italic">Encentrum (Parencentrum) walterkostei</Emphasis> n. sp., a new dicranophorid rotifer (Rotatoria: Monogononta) from the high alpine zone of the Central Alps (Austria)

Leaf litter processing rates and fungal biomass on leaf detritus were compared in four streams of different water chemistry. The streams drained catchments underlain by different bedrock types and varied in mean pH from 4.3 to 7.5 and in mean alkalinity from 0.0 to 35.8 mg CaCO₃ l^–1. Processing rates were fastest in WS3 and WS4, which had a pH of 6.0; slowest in SFR, which had a pH of 4.3; and intermediate in HSR which had a pH of 7.5. Fungal biomass as measured by the fungal sterol, ergosterol, was similar in WS3, WS4, and HSR but was much lower in SFR. These results suggest that reduced processing rates in SFR were associated in part with reduced fungal biomass on the leaves, whereas reduced processing rates in HSR were not related to differences in fungal biomass on the leaves.The Unit is jointly sponsored by the U.S. Fish and Wildlife Service, the West Virginia Division of Natural Resources, West Virginia University, and the Wildlife Management Institute.     

Colonization pattern of aquatic hyphomycetes on leaf packs in subtropical stream

Steralized leaf pieces of eight plants (Eucalyptus rostrata, Phoenix dactylifera, Phragmites australis, Musa nana, Salix subserrata, Cyperus alopecuroides, Ricinus communis and Eichhornia crassipes) were submerged in the Nile stream. Thirty-nine species of aquatic hyphomycetes were colonized on the plant leaves. Eucalyptus was the best substratum (30 species) for colonization by aquatic hyphomycetes. Phoenix (14 species), Phragmites (11 species), Salix (9 species), Musa (8 species), Ricinus and Cyperus (6 species) were also good substrata for aquatic hyphomycetes colonization. Echhornia (aquatic plant) was not suitable for aquatic hyphomycetes colonization. Alatospora acuminata, Triscelophorus monosporus and Tetracladium marchalianum were found to be the major colonizers on all leaf materials. Temperature and dissolved oxygen were the highest physico-chemical parameters affecting the aquatic hyphomycetes colonization. These results indicate that aquatic hyphomycetes have been shown to be successful colonizers on plants leaf in river Nile in Egypt as subtropical region. This revised version was published online in June 2006 with corrections to the Cover Date.     

<Emphasis Type="Italic">Nimbya alternantherae</Emphasis> a potential biocontrol agent for alligatorweed, <Emphasis Type="Italic">Alternanthera philoxeroides</Emphasis>

Alligatorweed, (Alternanthera philoxeroides (Mart.) Griseb.), an aquatic and wetland plant native to South America, is an aggressive weed in many parts of the world. Its ability to compete with other native plants and to impede waterways has made it a serious threat to aquatic ecosystems. Although biological control with insects has been fairly successful in aquatic habitats, there is a need for additional agents to manage the weed in upland sites. Accordingly, in a survey in Brazil in 1997 a fungus, Nimbya (=Alternaria) alternantherae (Holcomb and Antonopoulus) Simmons and Alcorn, was discovered and confirmed to be highly damaging to alligatorweed. Studies were conducted to determine the potential of this fungus for controlling this weed. Several isolates from Brazil, USA, and Puerto Rico were compared and no differences in virulence were observed, although a lower dew requirement was demonstrated for the Brazilian isolates. Conidia were more effective than mycelial suspension, and inoculum concentrations of 1×10⁵ and 1×10⁶ conidia per ml provided significant levels of control of the weed in greenhouse and field experiments, respectively. In a host-range study, N. alternantherae infected 6 plant species from a total of 42 species belonging to 23 families. N. alternantherae has the potential to be an effective mycoherbicide for alligatorweed.     

Breakdown of Introduced and Native Leaves in Two Indian Streams

The decomposition of leaves of Ficus benghalensis. Anacardium occidentale. Acacia auriculiformis and Eucalyptus globulus was followed during 16 weeks in two streams in the Western Ghat forest region of Karnataka, India. The concentration of nitrogen increased during decay; the levels of phosphorus, soluble phenolics and calcium decreased. Fungal colonization of the leaves was followed by counting the numbers of conidia released during aeration. Highest conidium production was found on leaves of Ficus: benghalensis. Daily exponential decay coefficients κ where not significantly different between leaf species or streams and varied between −0.0063 and −0,0090. Correlation analyses between κ and initial leaf parameters (N, P, Ca, and phenolics) did not yield any significant values, but there was a significant linear correlation between κ values and log (maximum sporulation rate).     

New observations onMonotosporella rhizoidea

Monotosporella rhizoidea is described, and illustrated with ligh and scanning electron micrographs, from submerged wood in Hong Kong. Our collection differs from the protologue, in having smaller conidia and longer condidiophores. The formation of multiple lobes which swell downwards over the conidiophore or existing conidiogenous cells is an unusual feature inMonotosporella. A synopsis and a key, as well as diagrammatic representations of the species ofMonotosporella are provided.     

Response of Aquatic Hyphomycete Communities to Changes in Heavy Metal Exposure

Decomposition of Alnus glutinosa (alder) leaves was studied in a severely (site H4) and a moderately (site H8) heavy metal polluted stream in the former copper shale mining district of Mansfeld, Central Germany. Leaves at H8 had reduced fungal diversity and spore production but a high exponential decay rate (k = 0.065). No further mass loss of leaves occurred at H4 after 4–6 weeks, and fungal diversity and spore production were lower than in H8. Decay and sporulation rates gradually increased to values of H8 control leaves in leaves preincubated in H4 and then transferred to H8. These increases correlated with the invasion of transplanted leaves by Tetracladium marchalianum and Tricladium angulatum. In the reverse transplant experiment (H8 to H4), mass loss appeared to stop immediately. Sporulation rates also declined, but remained consistently above levels in H4 control leaves. Leaves precolonized in the laboratory by one of three aquatic hyphomycete species exhibited increased decay rates in both streams. Sporulation rates on these leaves were greater than those of control leaves in H4, but smaller than those of control leaves in H8. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

喀麦隆塞玛岭地区溪流中的水生丝孢菌区系

Aquatic hyphomycetes on submerged fallen leaves and deadwoods have been numerously reported in fast running streams in temperate countries(Ingold,1976;Ingold,1979;Chauvet,1990;Barlocher & Rosset,1987;Barlocher et al.,1995;Descals et al.,1995).However,documented information is considerably limited in African countries(Ingold,1956;Dixon,1959;Le-John,1965;Ferreira et al.,1981),and unavailable in Cameroon,a country mostly covered with heavy tropical forests(Loung,1980).This paper is to present a list of aquatic and aeroaquatic hyphomycetes identified from foam samples collected in Cameroon during a two-year survey.     

北京地区水泡中的丝孢菌及其生态

本文报道北京及其邻近地区4个水域泡沫中的水生丝孢菌14属21种,其中6属11种为中国新记录,它们是:粗水线孢Anguillospora crassa Ingold,膨顶节枝孢Articulospora inflata Ingold,四节枝孢A.tetracladia Ingold,立水枝孢Dendrospora erecta Ingold,梯状小双枝孢Diplocladiella scalaroides Arnaud,星状小钉孢Heliscella stellata(Ing.&Cox)Nilsson ex Marvanova&Nilsson,奴地疣钉孢Heliscus lugdunensis Saccardo&Therry,阿地放射孢Lemonniera alabamensis Sinclair＆Morgan,细丽三枝孢Tricladium gracile Ingold,明丽三枝孢T.splendens Ingold,和多枝变孢霉Varicosporium elodeae Kegel。同时讨论了这类真菌与其生态环境之间的相关性及其分布。