Phylogenetic diversity of culturable fungi in the Heshang Cave, central China

Abstract

Caves are nutrient-limited and dark subterranean ecosystems. To date, attention has been focused on geological research of caves in China, whilst indigenous microbial diversity has been insufficiently characterized. Here, we report the fungal diversity in the pristine, oligotrophic, karst Heshang Cave, central China, using a culture-dependent method coupled with the analysis of the fungal rRNA-ITS gene sequences. A total of 194 isolates were obtained with six different media from 14 sampling sites of sediments, weathered rocks, and bat guanos. Phylogenetic analysis clustered the 194 sequenced isolates into 33 genera within 15 orders of three phyla, Ascomycota, Basidiomycota, and Zygomycota, indicating a high degree of fungal diversity in the Heshang Cave. Notably, 16 out of the 36 fungal genera were also frequently observed in solution caves around the world and 23 genera were previously found in carbonate cave, indicating potential similarities among fungal communities in cave ecosystems. However, 10 genera in this study were not reported previously in any solution caves, thus expanding our knowledge about fungal diversity in cave ecosystems. Moreover, culturable fungal diversity varied from one habitat to another within the cave, being the highest in sediments, followed by weathered rocks and bat guanos as indicated by α-diversity indexes. At the genus level, Penicillium accounted for 40, 54, and 52% in three habitats of sediments, weathered rocks, and bat guanos, respectively. Trichoderma, Paecilomyces, and Aspergillus accounted for 9, 22, and 37% in the above habitats, correspondingly. Despite of the dominance of Penicillium in all samples, β-diversity index indicated significant differences between each two fungal communities in the three habitats in view of both the composition and abundance. Our study is the first report on fungal communities in a natural pristine solution cave system in central China and sheds light on fungal diversity and functions in cave ecosystems.

Diversity and antimicrobial activity of endophytic fungi isolated from Securinega suffruticosa in the Yellow River Delta

“…The endophytic fungi were separated and purified following the methods reported [23]. The samples were washed repeatedly under running tap water, removing the surface soil and appendages.…”

Antimicrobial activities of culturable microorganisms (actinomycetes and fungi) isolated from Chaabe Cave, Algeria

“…Taking their similarities to sequences in GenBank, we identified 5 species: Readeriella eucalypti, Cladosporium pseudocladosporioides, Aspergillus wentii, Penicillium brevicompactum, Amphicorda felina (= Isaria felina = Beauveria felina). Man et al (2015) studying the phylogenetic diversity of culturable fungi in the Heshang Cave (China) reported that the genus Penicillium was the most abundant and accounted for 40, 54, and 52% of cultivable fungi in the sediments, weathered rocks and bat guano, respectively. Some other abundant fungal genera were Trichoderma, Paecilomyces, and Aspergillus, but in weathered rocks the presence of Cladosporium and Beauveria felina were also significant.…”

The Relationship between pH and Bacterial Communities in a Single Karst Ecosystem and Its Implication for Soil Acidification

“…To test the hypothesis, we investigated the correlation between environmental factors, especially pH, and microbial communities in a full karst ecosystem, from the surface soils overlying the cave system and from various habitats within the cave, including epikarstic drip waters that link the surface to subsurface ( Figure 1B ). Although microbial communities have been separately investigated from drip waters in caves (Liu et al, 2010; Yun et al, 2016), cave sediments (Man et al, 2015; Wu et al, 2015), weathered rocks in caves (Ward et al, 2009; Man et al, 2015), soils overlying cave systems (Castro et al, 2010; Ortiz et al, 2014), and bat guano (Man et al, 2015), no systematic evaluation of the communities throughout a karst system has been conducted previously. The results from this study provide an assessment of bacterial communities in central China karst and reveal the potential consequence of acidification on bacterial community composition in the karst habitats.…”