Corresponding authors: Xiang Sun (
Academic editor: P. Divakar
Halophytes have high species diversity and play important roles in ecosystems. However, endophytic fungi of halophytes in desert ecosystems have been less investigated. In this study, we examined endophytic fungi associated with the stem and root of ten halophytic species colonizing the Gurbantonggut desert. A total of 36 endophytic fungal taxa were obtained, dominated by
Li J-L, Sun X, Zheng Y, Lü P-P, Wang Y-L, Guo L-D (2020) Diversity and community of culturable endophytic fungi from stems and roots of desert halophytes in northwest China. MycoKeys 62: 75–95.
Endophytic fungi live within plant organs for some time or throughout their life, without causing apparent harm to their host (
The endophytic fungal colonization rate, diversity, and community composition is affected by host species, tissue types, and abiotic factors (e.g.,
Halophytes constitute about 1% of the world’s flora, survive and reproduce in saline habitats such as coastal and salinized inland regions (
Inland halophytes form extensive symbiotic relations with endophytic fungi in harsh environments, which benefit their hosts by promoting resistance against high salinity stress (
In order to improve our understanding of the endophytic fungi of desert halophytes, we selected ten halophyte species in the Gurbantonggut desert, Xinjiang, northwest China. The endophytic fungi were isolated from the stems and roots of halophytes and identified according to morphological characteristics and molecular data. This study aimed to reveal how the colonization rate, diversity, and community composition of endophytic fungi differed among halophytes species and tissue types. Besides, it will also provide preliminary data of halophyte endophytes for future studies in bioactive natural products, ecosystem reconstruction, or agricultural application in desert regions.
The study was carried out at the Fukang Desert Ecosystem Observation and Experiment Station, Chinese Academy of Sciences, located in the southern edge of the Gurbantonggut desert in China (44°17'N–44°22'N, 87°55'E–87°56'E, 448–461 m above sea level). The site has a continental arid temperate climate, with an annual mean temperature of 6.6 °C (a maximum of 44.2 °C in hot, dry summer and a minimum of -42.2 °C in freezing winter) (
On 30th July 2015, we selected ten halophyte species
Since most of the plant species involved in the current study (except for
Surface sterilization was conducted according to
Subcultures on
Genomic DNA was extracted from fresh cultures following the protocol of
The internal transcribed spacer (
A value of 97% of
Molecular identification of endophytic fungi based on
Fungal taxa | accession no. | Closest blast match in GenBank (accession no.) | Identity (%) | UNITE taxon name (SH code at 1.5% threshold) |
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100 | ||
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99 | ||
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100 | ||
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100 | ||
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100 | ||
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100 | ||
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100 | ||
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100 | ||
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100 | ||
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99 | ||
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99 | ||
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100 | ||
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100 | ||
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100 | ||
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100 | ||
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99 | ||
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97 | ||
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97 | |||
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100 | ||
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94 | |||
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97 | |||
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96 | |||
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100 | ||
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97 | ||
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88 | |||
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86 | |||
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96 | |||
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92 | |||
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99 | |||
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99 | ||
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99 | ||
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88 | |||
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86 | |||
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100 | ||
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100 | ||
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98 |
All statistical analyses were carried out in R 3.3.1 (
One-way analysis of variance (
The host-fungus association preferences were evaluated based on a
A total of 1046 fungal strains were recovered from 1600 tissue segments from ten halophyte species. The colonization rate of endophytic fungi ranged from 7.5 ± 3.33% to 83.75 ± 8.95% in stems, from 33.75 ± 11.19% to 97.5 ± 1.67% in roots, and from 38.75 ± 2.46% to 85.63 ± 2.28% overall for the entire plant among the ten halophyte species (Fig.
Colonization rate of endophytic fungi in stem, root, and total (stem + root) tissues of the ten halophyte species. Data are means ± SE (n = 10). Columns without shared lowercase, uppercase, and italic letters denote the significant difference in the stem, root, and total tissues among the halophyte species, respectively. Asterisks above bars indicate significant difference between stem and root tissues for each plant species (**
In total, 36 fungal taxa were isolated and identified based on morphological characters and
Endophytic fungal richness in stem, root and total (stem + root) tissues of the ten halophyte species. Data are means ± SE (n = 10). Columns without shared lowercase, uppercase, and italic letters denote significant difference in the stem, root, and total tissues among the plant species, respectively. Asterisks above bars indicate the significant difference between stem and root tissues for each halophyte species (*
Of the 36 endophytic fungi, 32 were recovered from roots, 27 from stems, and 23 were common in both roots and stems (Fig.
The
Relative abundance of endophytic fungi in the stem and root tissues of the ten halophyte species.
Relative abundance of endophytic fungi in the stem and root of different halophyte species.
Canonical correspondence analysis (
Host-fungus association preference analysis showed that five out of ten halophyte species showed significant preferences to endophytic fungi, especially strong preferences in
Preferences observed in the plant-fungus associations.
The colonization rate and species richness of endophytic fungi varied among desert halophyte species in the current study. Similar results have been reported in previous studies in mangrove (
We found that the endophytic fungi community composition is halophyte species-dependent. Similar results have been reported in some previous studies on halophytes and desert plants (
Community composition of endophytic fungi was also affected by plant tissue types (root and stem), which corroborate earlier studies carried out in semi-arid and arid ecosystems (
The present study revealed high diversity of endophytic fungi associated with desert halophytes, and their colonization rate and diversity of endophytic fungi vary from plant to plant and is higher in roots than in stems. The endophytic fungal community composition is affected by plant species and tissue type as some endophytic fungi showed strong host and tissue preferences. The current study will provide preliminary data for exploration into diverse bioactive natural products originated from halophyte endophytes, and prospects on ecosystem reconstruction or desert agriculture development.
We are grateful to Ms. Tie-Mu-Er-Bie-Ke Ba-He-Jia-Yi-Na-Er, Mr. Yong-Xin Zang and Hai Zhu from Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences for their help with sampling and plant identification. This study was financially supported by the National Natural Science Foundation of China (Grant Nos. 31470151 and 31470228).