Ophiocordyceps sinensis is a fungus that parasitizes caterpillars, and more than 30 species of filamentous fungi have been isolated from its fruiting body. However, its microbiological diversity remains unclear. Based on the clone library and quantitative PCR techniques, the bacterial flora and mycobiota of 3 different samples (larva, stromata/sclerotia, and surface soil) from natural O. sinensis specimens were investigated using primer sets that targeted the 16S rRNA gene and internal transcribed spacer region of ribosomal DNA. The results showed that the abundance of bacterial and fungal communities in the soil attached to the surface of O. sinensis was (6.4 ± 1.4) × 10(6) and (6.0 ± 0.3) × 10(7) copies/g dry matter, respectively, which was the highest compared with that in the larva and stromal samples. The main groups of bacteria in the O. sinensis samples were Proteobacteria and Actinobacteria, while Ascomycota was the most dominant fungal group in the 3 samples. At the genus level, Geomyces, Phoma, and Trichocladium were the dominant genera in the larval sample, while Geomyces and Cladosporium were the dominant genera in the stromal sample. In conclusion, a great number of bacterial and fungal species were present in naturally occurring O. sinensis specimens, and there was a high diversity of bacterial and fungal communities. These findings contribute to the understanding of the bacterial and fungal community structure of this valuable medicinal fungus and lay the foundation for the future discovery of new medicinal microorganism resources.

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Chinese Cordyceps, known in Chinese as “DongChong XiaCao”, is a parasitic complex of a fungus (Ophiocordyceps sinensis) and a caterpillar. The current study explored the endogenetic fungal communities inhabiting Chinese Cordyceps. Samples were collected from five different geographical regions of Qinghai and Tibet, and the nuclear ribosomal internal transcribed spacer-1 sequences from each sample were obtained using Illumina high-throughput sequencing. The results showed that Ascomycota was the dominant fungal phylum in Chinese Cordyceps and its soil microhabitat from different sampling regions. Among the Ascomycota, 65 genera were identified, and the abundant operational taxonomic units showed the strongest sequence similarity to Ophiocordyceps, Verticillium, Pseudallescheria, Candida and Ilyonectria Not surprisingly, the genus Ophiocordyceps was the largest among the fungal communities identified in the fruiting bodies and external mycelial cortices of Chinese Cordyceps. In addition, fungal communities in the soil microhabitats were clustered separately from the external mycelial cortices and fruiting bodies of Chinese Cordyceps from different sampling regions. There was no significant structural difference in the fungal communities between the fruiting bodies and external mycelial cortices of Chinese Cordyceps. This study revealed an unexpectedly high diversity of fungal communities inhabiting the Chinese Cordyceps and its microhabitats.

The quantitative knowledge of global forest litterfall is very important for understanding the global biogeochemical cycle and evaluating of forest ecosystem services. Our aims are to show the spatio‐temporal patterns of forest litterfall and the variation in different forest types and climate zones in the world. We compiled the global forest litterfall dataset of 2347 total litterfall and 1507 leaf litterfall measurements by a survey of literature published. The total litterfall and leaf litterfall were estimated in 2000 and 2009, respectively, through raster and vector calculation based on remote sensing‐based global vegetation cover data. The total litterfall and leaf litterfall were 31.5 Pg and 22 Pg in 2000 and 26 Pg and 18 Pg in 2009, respectively. The spatial pattern of litterfall and leaf litterfall at global scale between 2000 and 2009 was generally similar. The largest fractions of forest litterfall were in evergreen broadleaved forests (37%), followed by needle‐leaved forests (25%), deciduous broadleaved forests (20%), and others (18%) in 2000. The order of the fractions for forest litterfall was the tropical (50%), boreal (24%), temperate (17%), and subtropical forests (9%) in 2000. The ratios of leaf litterfall to litterfall were 70% in 2000 and 72% in 2009. The variability of global litterfall was most explained by the actual evapotranspiration. The reduction in total litterfall and leaf litterfall between 2000 and 2009 was coupled with the decrease in forest areas. The GIS‐based geostatistics combining with the regression model represents a powerful approach for estimating the global spatial distribution, composition, and magnitude of litterfall.

Aim The aim of this study is to determine the patterns of nitrogen (N) concentrations in leaf litter of forest trees as functions of climatic factors, annual average temperature (Temp, ° C) and annual precipitation (Precip, dm) and of forest type (coniferous vs. broadleaf, deciduous vs. evergreen, Pinus , etc.). LocationThe review was conducted using data from studies across the Eurasian continent.Methods Leaf litter N concentration was compiled from 204 sets of published data (81 sets from coniferous and 123 from broadleaf forests in Eurasia). We explored the relationships between leaf litter N concentration and Temp and Precip by means of regression analysis. Leaf litter data from N 2 -fixing species were excluded from the analysis. ResultsOver the Eurasian continent, leaf litter N concentration increased with increasing Temp and Precip within functional groups such as conifers, broadleaf, deciduous, evergreen and the genus Pinus . There were highly significant linear relationships between ln(N) and Temp and Precip ( P < 0.001) for all available data combined, as well as for coniferous trees, broadleaf trees, deciduous trees, evergreen trees and Pinus separately. With both Temp and Precip as independent variables in multiple regression equations, the adjusted coefficient of determination ( ) was evidently higher than in simple regressions with either Temp or Precip as independent variable. Standardized regression coefficients showed that Temp had a larger impact than Precip on litter N concentration for all groups except evergreens. The impact of temperature was particularly strong for Pinus . ConclusionsThe relationship between leaf litter N concentration and temperature and precipitation can be well described with simple or multiple linear regression equations for forests over Eurasia. In the context of global warming, these regression equations are useful for a better understanding and modelling of the effects of geographical and climatic factors on leaf litter N at a regional and continental scale.