Background Revealing the relationship between plants and fungi is very important in understanding biodiversity maintenance, community stability, and ecosystem functioning. However, differences in the community and network structures of phyllosphere epiphytic and endophytic fungi are currently poorly documented. In this study, we examined epiphytic and endophytic fungal communities associated with the leaves of six mangrove species using Illumina MiSeq sequencing of internal transcribed spacer 2 (ITS2) sequences. Results A total of 635 operational taxonomic units (OTUs) of endophytic and epiphytic fungi were obtained at a 97% sequence similarity level; they were dominated by Dothideomycetes and Tremellomycetes . Plant identity had a significant effect on the OTU richness of endophytic fungi, but not on epiphytic fungi. The community composition of epiphytic and endophytic fungi was significantly different, and plant identity had a greater effect on endophytic fungi than on epiphytic fungi. Network analysis showed that both epiphytic and endophytic network structures were characterized by significantly highly specialized and modular but lowly connected and anti-nested properties. Furthermore, the endophytic network had higher levels of specialization and modularity but lower connectance and stronger anti-nestedness than the epiphytic network. Conclusions This study reveals that the phyllosphere epiphytic and endophytic fungal communities differ, and plant identity has a greater effect on the endophytic fungi than on epiphytic fungi. These findings demonstrate the role of host plant identity in driving phyllosphere epiphytic and endophytic community structure. Electronic supplementary material The online version of this article (10.1186/s40168-019-0671-0) contains supplementary material, which is available to authorized users.

Pestalotiopsis is a taxonomically confused, pathogenic and chemically creative genus requiring a critical reexamination using a multi-gene phylogeny based on ex-type and ex-epitype cultures. In this study 40 isolates of Pestalotiopsis, comprised of 28 strains collected from living and dead plant material of various host plants from China were studied by means of morphology and analysis of ITS, β-tubulin and tef1 gene sequence data. Based on molecular and morphological data we describe 14 new species (Pestalotiopsis asiatica, P. chinensis, P. chrysea, P. clavata, P. diversiseta, P. ellipsospora, P. inflexa, P. intermedia, P. linearis, P. rosea, P. saprophyta, P. umberspora, P. unicolor and P. verruculosa) and three species are epitypified (P. adusta, P. clavispora and P. foedans). Of the 10 gene regions (ACT, β-tubulin, CAL, GPDH, GS, ITS, LSU, RPB 1, SSU and tef1) utilized to resolve cryptic Pestalotiopsis species, ITS, β-tubulin and tef1 proved to be the better markers. The other gene regions were less useful due to poor success in PCR amplification and/or in their ability to resolve species boundaries. As a single gene tef1 met the requirements for an ideal candidate and functions well for species delimitation due to its better species resolution and PCR success. Although β-tubulin showed fairly good differences among species, a combination of ITS, β-tubulin and tef1 gene data gave the best resolution as compared to single gene analysis. This work provides a backbone tree for 22 ex-type/epitypified species of Pestalotiopsis and can be used in future studies of the genus.

The mycota and decomposing potential of endophytic fungi associated with Acer truncatum, a common tree in northern China, were investigated. The colonization rate of endophytic fungi was significantly higher in twigs (77%) than in leaves (11%). However, there was no significant difference in the colonization rates of endophytic fungi between lamina (9%) and midrib (14%) tissues. A total of 58 endophytic taxa were recovered using two isolation methods and these were identified based on morphology and ITS sequence data. High numbers of leaf endophytes were obtained in the method to determine decomposition of leaves by the natural endophyte community (35 taxa) as compared to disk fragment methodology (9 taxa). The weight loss in A. truncatum leaves decomposed by endophyte communities increased with incubation time; the weight loss was significantly higher at 20 weeks than at 3 and 8 weeks. Both common and rare endophytic taxa produced extracellular enzymes in vitro and showed different leaf decay abilities. Our results indicated that the composition and diversity of endophytic fungi obtained differed using two isolation methods. This study suggests that endophytic fungi play an important role in recycling of nutrients in natural ecosystems.