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Article

Identification, Antimicrobial and Plant Growth Promoting Activities of Endophytic Fungi Associated with Cynomorium songaricum Rupr., a Traditional Medicinal Plant in Mongolia

by
Enkh-Amgalan Jigjiddorj
*,
Amarbayasgalan Maidarjav
,
Bumtsend Byambasuren
and
Daritsogzol Nyamgerel
Institute of Biology, Mongolian Academy of Sciences, Enkhtaivan Avenue 54b, Ulaanbaatar 13330, Mongolia
*
Author to whom correspondence should be addressed.
Diversity 2024, 16(2), 122; https://doi.org/10.3390/d16020122
Submission received: 31 December 2023 / Revised: 8 February 2024 / Accepted: 11 February 2024 / Published: 14 February 2024
(This article belongs to the Special Issue Feature Papers in Microbial Diversity and Culture Collections)
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Abstract

:
Endophytic fungi colonize the inner tissues and provide direct and indirect benefits to plants. Although Mongolia is rich in medicinal plants, due to climatic and anthropogenic reasons, the resources are being depleted, and many species are under threat of gradual extinction, while the endophytic fungi of Mongolian plants are largely unknown. In this study, a total of 24 culturable endophytic fungal strains were isolated from Cynomorium songaricum (Rupr.), a medicinal and vulnerable plant species of Mongolia. Based on the morphological characteristics and the sequences of the rDNA internal transcribed spacer (ITS) region, the isolates were identified into six genera: Fusarium (8), Clonostachys (7), Penicillium (6), Alternaria (1), Aspergillus (1), and Madurella (1). The antimicrobial activity was assessed by the agar-diffusion method, revealing that 15 strains were able to inhibit the growth of at least one of the test organisms. Among them, 1 strain showed inhibitory activity against Escherichia coli, 12 against Bacillus subtilis, 13 against Staphylococcus aureus, and 8 against Aspergillus niger, respectively. The ability to solubilize complex phosphorus and zinc minerals was observed in 3 and 21 strains, respectively, and the production of indole-3-acetic acid (IAA) was detected in nine strains in the presence of tryptophan. Our study provides the first insight into the cultivable endophytic fungal composition of C. songaricum, parasitizing the roots of Nitraria sibirica growing in the Gobi Desert of Mongolia. The resulting fungi, which have antimicrobial and plant growth-promoting properties, were preserved in the national culture collection and can be used to further exploit their biotechnological potential, as well as for the propagation of endangered and vulnerable medicinal plants.

Graphical Abstract

1. Introduction

To implement the Convention on Biological Diversity [1] and the Law on Genetic Resources of Mongolia, which entered into force on 30 December 2021 [2], the establishment and maintenance of facilities for ex situ conservation of biological diversity, research, and management of the collection of biological resources, especially microorganisms, are in demand in Mongolia. Mongolia is one of the countries most affected by climate change, with a temperature increase of 2.14 °C confirmed between 1940 and 2008 [3], which can lead to the loss of biodiversity. In addition to climatic reasons, overexploitation makes medicinal plants more vulnerable. Therefore, we focus on endophytic microorganisms, isolate the key culturable representatives residing in the medicinal, endangered, and vulnerable plants in Mongolia, preserve them in the culture collection, and explore their biotechnological potential for further sustainable use.
Endophytic fungi are microorganisms that live in internal plant tissue for at least a certain period of their life cycle without causing harm to the host plant under any circumstance [4]. They are well known to provide direct (nutrient acquisition and phytohormone production) and indirect (activation of systemic resistance, production of secondary metabolites, and protection for abiotic and biotic stresses) benefits to the host plant [5]. The direct benefits of endophytic fungi result in enhanced root development, increased plant height, biomass production, and overall yield; hence, they can be referred to as biofertilizers [6]. Phosphorus is the second most important nutrient for overall plant development and productivity. However, its structural and chemical characteristics make it a limiting nutrient for plant growth by reducing its free availability [7]. Zinc is one of the essential micronutrients for plants, and a deficiency of this element leads to a decrease in the quality of the crop. Zinc-solubilizing microorganisms can solubilize the inaccessible form of zinc by secreting organic acids, siderophores, and other chelating compounds, but this property is well known to bacteria and, to a lesser extent, fungi [8]. Endophytic fungi produce phytohormones such as auxins, gibberellins (GAs), and cytokinins, and indole-3-acetic acid (IAA) is the main auxin produced by endophytes [5].
Over the past several years, endophytic fungi have attracted attention due to their ability to produce novel bioactive secondary metabolites and have become known as a treasure house of bioactive compounds of medicinal importance [9]. Their metabolites are progressively being studied, and metabolites are categorized into various functional groups: alkaloids, benzopyranones, chinones, flavonoids, phenolic acids, quinones, steroids, saponins, tannins, terpenoids, tetralones, xanthones, and many others that serve as a potential candidate for antimicrobial, anti-insect, anticancer and many more properties [10,11,12,13]. However, it is estimated that only 1–2% of approximately 300,000 plant species have been studied, meaning that the vast majority of endophytic fungal symbiotic relationships remain unexplored [14].
Cynomorium songaricum Rupr., called Ulaan goyo or Zuungariin goyo in Mongolia, is a medicinal, parasitic, and rare plant species distributed in southern Mongolia and northwest Inner Mongolia in China [15]. This plant usually parasitizes the roots of Nitraria tangutorum Bobr. and Nitraria sibirica Pall. located in dry sandy regions, and it is widely used as a functional food and medicine in traditional Mongolian medicine and traditional Chinese medicine [16]. In traditional Mongolian medicine, it has been used to treat kidney diseases, high blood pressure, liver and bile dysfunction, diabetes, weakness, dropsy, nervousness, and constipation [17]. Numerous studies on the bioactive compounds and functions of C. songaricum have been conducted worldwide, and Cui et al. summarized them and reported that at least 76 biologically active compounds had been isolated and identified from this amazing plant species, including flavonoids, terpenoids, steroids, organic acids, saccharides, glycosides, and phloroglucinol adducts. These compounds have pharmacological functions, such as anti-aging, anti-oxidation, anti-fatigue, and anti-HIV effects, as well as effects on the immune system, nervous system, reproductive system, and other biological activities [16]. Despite extensive research on the bioactive compounds and pharmacological actions of the plant, a study on the distribution and dynamics of endophytic fungi in C. songaricum and its host N. tangutorum was first reported in 2018, suggesting a possible exchange of endophytic fungi between them. Also, some of the isolates, such as Fusarium spp., exhibited the ability to promote seed germination of C. songaricum [18]. Further investigations revealed significant correlations between differential secondary metabolites and endophytic fungi in C. songaricum distributed across different locations [19], and moreover, plant species and lifestyle, as well as the local environment, strongly influenced the abundance and diversity of the endophytic fungal species in C. songaricum and its host N. tangutorum [20].
Therefore, the diversity of endophytic fungi in C. songaricum that parasitizes other host plant species growing in geographically distant locations and under different environmental conditions is of great interest. N. sibirica Pall. has a higher salt tolerance than N. tangutorum Bobr. [21], and its fruits have the highest total content of flavonoids and crude protein among the three species (N. sibirica Pall., N. tangutorum Bobr. and Nitraria roborowskii Kom.) [22].
In this study, culturable endophytic fungal strains were isolated and identified from Cynomorium songaricum Rupr. parasitizing on the roots of Nitraria sibirica Pall., and their antimicrobial activity, as well as their plant growth-promoting properties, such as phosphate solubilization, zinc solubilization, and IAA production, were determined.

2. Materials and Methods

2.1. Collection of Plant Samples

Samples of the medicinal and vulnerable plant Cynomorium songaricum Rupr. were collected in July 2021 at a site (45°34′43″ N, 98°13′12″ E) located at an altitude of 1730 m above sea level in a desert area in the Govi-Altai province of Mongolia. The Gobi Desert is a cold desert with average temperature fluctuations from below – 20 °C in winter to over 33 °C in summer. Precipitation is over 200 mm in the Gobi-Altai mountains (sampling area) compared to the extreme arid areas of the Gobi Desert, where it is less than 40 mm [23]. The aboveground and underground parts, as well as fresh and old rhizomes on the root of the host plant Nitraria sibirica Pall. were collected (Figure 1).

2.2. Isolation of Endophytic Fungi

Plant samples were subjected to a three-step surface sterilization procedure according to the method described by Thi Minh Le et al. [24] but with minor modifications. Portions of healthy parts and rhizomes were washed thoroughly under running tap water to remove adhered debris, and then each sample was sterilized sequentially by washing with 70% ethanol for 1 min, 3% sodium hypochlorite for 4 min, and 70% ethanol for 1 min, rinsed three times in sterile distilled water. After drying on sterile filter paper, each sample was cut into small pieces of less than 1 cm in size with a sterile scalpel and placed on a potato dextrose agar (PDA, Biolab Diagnostics Laboratory Inc., Budapest, Hungary) supplemented with 50 mg/L chloramphenicol to suppress bacterial growth. All plates were incubated at 28 °C, and the growth of endophytic fungal hyphae emerging from the segments was monitored daily for up to 3 weeks. Emerging fungi were transferred to fresh PDA plates, incubated for 1–2 weeks, and periodically checked for purity. The effectiveness of the surface sterilization procedure was ascertained by spreading 200 mL of the last wash water on the agar plates and incubating at 28 °C for 1 week to check for microbial growth. The pure cultures were preserved in glycerol suspensions (20%, v/v) at −80 °C.
All isolated fungi were deposited into the Mongolian National Culture Collection of Microorganisms (MNCCM), Institute of Biology, Mongolian Academy of Sciences.

2.3. Identification of the Isolates

Fungal isolates were cultured on a low carbon agar (LCA) medium composed of glucose 1 g/L, potassium dihydrogen phosphate 1 g/L, magnesium sulfate 0.2 g/L, potassium chloride 0.2 g/L, sodium nitrate 2 g/L, yeast extract 0.2 g/L, and agar 15 g/L at 28 °C for 7 days. The purity and monosporic cultures were confirmed by observing the isolates under an Olympus CX41 microscope (Olympus, Japan) at magnifications of 40–500×, and spore-forming fungi were preliminarily identified by morphological features, such as conidia, conidiophores, and hyphae [25].
Molecular identification was carried out using fungal isolates grown on a PDA at 28 °C for 7 days [26]. Total genomic DNA was extracted using the PrepMan™ Ultra Sample Preparation Reagent (Thermo Fisher Scientific Inc., Foster, CA, USA) according to the manufacturer’s instructions.
The internal transcribed spacer (ITS) region, 5.8S gene and the D1/D2 domain of the large subunit (LSU) ribosomal RNA (rRNA) gene were amplified using the primers ITS5 (5′-GGAAGTAAAAGTCGTAACAAGG-3′) and NL4 (5′-GGTCCGTGTTTCAAGACGG-3′) as described previously [27]. The amplification was performed with a FastStart Taq DNA polymerase (Roche, China) in the GeneAmp® PCR System 9700 (Thermo Fisher Scientific Inc., USA) according to the following conditions: initial denaturation at 94 °C for 2 min, followed by 30 cycles of denaturation at 94 °C for 1 min, annealing at 56 °C for 30 s, and extension at 68 °C for 90 s, and a final extension step at 68 °C for 5 min. The PCR products were visualized by electrophoresis on 1% agarose gel and subsequently purified using an AccuPrep® PCR/Gel Purification Kit (Bioneer, Daejeon, Republic of Korea) and sent to Macrogen, Korea, for commercial sequencing. The sequences were analyzed by BLAST similarity search on the National Center for Biotechnology Information website (http://www.ncbi.nlm.nih.gov/BLAST) based on their identity values on 29 September 2023.
The obtained sequences were submitted to GenBank, and the accession numbers are LC663161- LC663164 and LC769415- LC769442.

2.4. Antimicrobial Activity Test

The endophytic fungal isolates were screened using the modified agar plug diffusion method for antimicrobial activity against potentially pathogenic bacteria [Escherichia coli (NBRC 102203T), Bacillus subtilis (NBRC 13719T), and Staphylococcus aureus (NBRC 100910T)] and two fungi [Candida albicans (NBRC 1385T) and Aspergillus niger (NBRC 33023T)] [28,29,30]. Inoculums of the test bacteria (approximately 1 × 108 CFU/mL) and yeast (approximately 1 × 106 CFU/mL) were prepared by comparison with 0.5 McFarland standards, whereas inoculums of test fungi were prepared as 1 × 106 spores/mL. The test bacterial inoculums were seeded on nutrient agar (Biolab Diagnostics Laboratory Inc., Hungary), and yeast and fungal inoculums were seeded on a PDA, respectively. For the preparation of the agar plug, the fungal isolates were precultured on PDA plates at 28 °C for 7 days, and then the cultures were cut into plugs 6 mm in diameter; the plugs were placed on the agar medium seeded with test microorganisms. The plates were incubated at either 37 °C (bacteria and yeast) or 30 °C (fungi). Ampicillin sodium (50 µg/disk) and cycloheximide (25 µg/disk) were taken as positive controls for bacteria and fungi, respectively. Antimicrobial activity was assessed by the size (diameter in mm) of sterile zones formed around the fungal agar plugs.

2.5. Phosphate and Zinc Oxide Solubilization Assay

Screening of fungal isolates for the ability to solubilize phosphate and zinc was carried out on Pikovskaya’s (PKV) agar medium and on mineral salts agar medium amended with 0.1% of insoluble ZnO, respectively, as described previously [31]. Agar plugs (6 mm), cut from a 14-day-old culture of endophytic fungi, were placed on the respective plates in triplicate and incubated at 28 °C. The clear zones formed around the colonies were measured after the incubation period, 4 days and 14 days after inoculation, for the efficiency of solubilization of phosphorus and zinc, respectively.

2.6. IAA Production Assay

The production of indole acetic acid (IAA) in endophytic fungi was determined using the following colorimetric assay. Fungal isolates were incubated in 5 mL of PDB supplemented with 5 mM of L-tryptophan at 28 °C for 5 days. After cultivation, each culture was centrifuged at 5000 rpm for 10 min, and 1 mL of the clear supernatant was mixed with 2 mL of Salkowski reagent (1 mL 0.5 M FeCl3, 50 mL 35% perchloric acid), and the mixture was incubated in the dark at room temperature for 20 min. A mixture of PDB medium with 5 mM of L-tryptophan and Salkowski reagent was used as a control. The development of a pink color indicated IAA production and the pink-to-red color produced by the isolates was categorized into low, medium, and high [32]. The absorbance of a positive reaction was determined with a UV–VIS spectrophotometer at 530 nm, and the amount of IAA product was calculated from a standard graph prepared using known quantities of pure IAA [31].

3. Results

3.1. Isolation and Identification of Endophytic Fungi

In the present study, a total of 24 purified isolates of endophytic fungi were obtained from aboveground parts (4), underground parts (4), fresh rhizomes (8), and old rhizomes (8) of Cynomorium songaricum Rupr. parasitizing on the roots of Nitraria sibirica Pall., growing in sandy soil in the Govi-Altai province territory of Mongolia. They were morphologically highly diverse and mainly pigmented on a PDA medium (Figure 2).
Molecular identification of fungal endophytes was performed using ITS rDNA sequences (ITS1-5.8S-ITS2) as a marker. ITS rDNA sequences from the 24 isolates were compared with sequences of organisms represented in the GenBank database. BLAST results showed that the 24 isolates belonged to six genera: Fusarium, Clonostachys, Penicillium, Alternaria, Aspergillus, and Madurella (Table 1). The genus Fusarium had the highest number of isolates (eight), followed by Clonostachys with seven isolates, Penicillium with six isolates, while the genera Alternaria, Aspergillus, and Madurella all had one isolate each.

3.2. Antimicrobial Activity

All isolates were evaluated in vitro for antimicrobial activity, and among the 24 isolates, 15 (62.5%) exhibited antimicrobial activity against at least one test microorganism, whereas the rest yielded no activity. There was 1 strain that had antimicrobial activity against Escherichia coli, 12 strains against Bacillus subtilis, 13 strains against Staphylococcus aureus, and 8 strains against Aspergillus niger (Table 2). Among the 15 antagonistic strains, 13 (86.6%) belonged to the genera Fusarium and Clonostachys. All seven strains belonging to Clonostachys and six out of eight strains belonging to Fusarium had antimicrobial activity. A strain (P26-ZN1-2) belonging to Madurella inhibited the growth of E. coli along with B. subtilis and S. aureus with inhibitory zones of 7.5 ± 0.7, 9.5 ± 2.1 and 15.5 ± 0.7, respectively. Moreover, eight strains (P26-H1-3, P26-H2-2, P26-ZN1-2, P26-ZO1-3, P26-ZO1-4, P26-ZO1-5, P26-ZO1-6, P26-ZO2-3) showed a broader spectrum of antimicrobial activity (inhibition zone, or against test bacteria and fungi, both), and two strains (P26-H2-2, P26-R2-1) displayed strong inhibition to the pathogenic fungus (i.e., Aspergillus niger). None of the strains inhibited the Candida albicans test (Table 2).

3.3. In Vitro Test for Plant Growth Promoting Traits of Endophytes

The endophytic isolates were further studied for their plant growth-promoting traits, including IAA production, phosphate solubilization, and zinc oxide solubilization (Table S2). All 28 strains exhibited positive results for one or more traits; IAA production was seen in nine strains in PDB medium supplemented with 5 mM L-tryptophan (Figure 3), whereas phosphate solubilization and zinc oxide solubilization activity was noticed in 3 and 21 strains, respectively (Figure 4). Three Penicillium strains, P26-ZN2-3, P26-ZN2-5, and P26-ZO1-1, were positive for both phosphate and zinc oxide solubilization traits; however, no production of IAA was detected in the presence and absence of L-tryptophan. Penicillium strain P26-ZN2-5 showed the most significant phosphate solubilizing activity on a solid PVK medium with a solubilization index (SI) of 2.16 ± 0.02 cm. This strain also showed the most significant zinc solubilizing activity on mineral salt agar with an SI of 3.4 ± 0.1 cm.

4. Discussion

It has been shown that the diversity of endophytic fungi is influenced by the plant genotype [33,34] or both the host genotype and geography combined [35]. A recent study by Miao et al. on speciation and genetic diversity of endophytic fungi from their host plants, C. songaricum, parasitized N. tangutorum, and non-parasitized N. tangutorum at three geographic locations, found that only 0.41% to 4.48% of endophytic fungal species were shared between their host plants, consistent with previous studies indicating that the plant genotype strongly affects the endophytic fungal composition [20].
A possible exchange of endophytic fungi between C. songaricum and its host N. tangutorum was previously suggested [18], so the endophytic fungal composition of C. songaricum parasitizing another host, N. sibirica Pall, growing in the Gobi Desert was of great interest. It is known that culture-based methods do not reflect the real diversity of fungi in a niche due to artificial selection pressure, and some of these microorganisms cannot be cultivated under laboratory conditions [18,36,37]. However, culturable endophytes are potential sources for applications in biotechnology, medicine, agriculture, and beyond.
In our study, representatives of the taxa Fusarium, Clonostachys, and Penicillium were predominant; representatives of Alternaria, Aspergillus, and Madurella were less prominent. Indeed, Fusarium spp., Penicillium spp., and Aspergillus spp. were the most abundant fungi isolated from C. songaricum parasitizing the roots of N. tangutorum [18] and among the fungal genera from plants reported in general [10,38,39]. More specifically, Fusarium dominated the underground tissues of Aristolochia chilensis growing in an arid ecosystem [39], C. songaricum parasitizing the roots of N. tangutorum, in general, and notably at the tubercle stage, and the fermentation broth of F. redolens (KY379544) promoted the germination of host plant seeds [18]. Strains of this genus were isolated in the greatest numbers and were also ubiquitously isolated from all tissue types of C. songaricum parasitizing the roots of N. sibirica and demonstrated antimicrobial and zinc-solubilizing activity, as well as IAA production. Further studies on these strains are awaited, considering the enormous potential of endophytic Fusarium in providing plant host defense and survival strategies reported so far [40].
The second prevalent genus was Clonostachys, with seven isolates having 99.13–100% similarity to Clonostachys rosea based on ITS sequences. This genus was less prominent in C. songaricum, parasitizing the roots of N. tangutorum; only 2 isolates were found out of 111 [18]. Clonostachys rosea is a well-recognized mycoparasite whose hyphae penetrate and destroy those of many host fungi, and there are several commercial products based on C. rosea available for biocontrol applications worldwide [41,42]. Moreover, Clonostachys fungi produce at least 229 secondary metabolites, such as nitrogen-containing metabolites, polyketides, and terpenoids, many of which exhibit biological activities, such as cytotoxic, antimicrobial, antileishmanial, antimalarial activity [43]. Most of our isolates assigned to the genus Clonostachys were found in old rhizomes, absent from fresh rhizomes, and exhibited both antibacterial and antifungal activity. Recently, Kapeua-Ndacnou et al. reported that certain Clonostachys endophytes from healthy tissues of Coffea species and mycoparasites of Hemileia, the coffee leaf rust (CLR), significantly reduced the severity of CLR [44].
Representatives of the genus Penicillium were isolated exclusively from fresh rhizomes. Interestingly, this genus also appears to be a prevalent endophyte in plant species native to the arid environments of the Atacama Desert, including Chenopodium quinoa, Prosopis chilensis, and Aristolochia chilensis [39,45,46]. Penicillium endophytes enhanced the growth of host plant P. chilensis by increasing PSII efficiency, nitrogen, and carbohydrate content in leaves [46] and helping C. quinoa respond better to drought stress [47]. Our Penicillium strains solubilized both phosphate and zinc but did not show antimicrobial activities. Penicillium spp. are known to be excellent solubilizers of phosphate [48,49,50] and zinc solubilizing efficiency to a lesser extent [51]. For example, P. bilaiae RS7B-SD1, associated with wheat roots, had the ability to solubilize significant amounts of rock phosphate [49], and another fungal strain, P. guanacastense JP-NJ2, solubilized phosphate by producing organic acids, extracellular acidic phosphatase and phytase, and promoted the growth of seedlings of pine Pinus massoniana [48]. In addition, there is a commercial inoculant of phosphate solubilizing Penicillium sold by NovoZymes (JumpStart®WP; NovoZymes). During the present study, Penicillium spp. solubilizing minerals found in fresh rhizomes suggest that they may play a role in promoting plant growth.
One isolate, P26-ZN1-2, was classified into the genus of Madurella. Species of Madurella are the most common agents of black-grain mycetoma [52]. However, in recent years, several Madurella strains have been isolated from different plant species as endophytes [53,54,55]. Madurella strain P26-ZN1-2 had antibacterial activity against Gram-negative and Gram-positive test bacteria and produced the highest amount of IAA.
Our study provides the first insight into the cultivable endophytic fungal composition of C. songaricum, a rare medicinal plant parasitizing the roots of N. sibirica growing in the Gobi Desert of Mongolia. The resulting fungi, which have antimicrobial and plant growth-promoting properties, can be used to further exploit their biotechnological potential and be applied to propagate endangered and vulnerable medicinal plants.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/d16020122/s1, Table S1: Concentration of IAA produced by endophytic fungi; Table S2: Phosphate and zinc solubilization index.

Author Contributions

Conceptualization: E.-A.J.; methodology: A.M., B.B., D.N. and E.-A.J.; investigation: A.M., B.B., D.N. and E.-A.J.; writing—original draft preparation: E.-A.J., A.M. and B.B.; writing—review and editing: E.-A.J.; visualization: E.-A.J. and B.B.; formal analysis: A.M., B.B., D.N. and E.-A.J., data curation: B.B. and D.N.; supervision: E.-A.J.; project administration: E.-A.J.; funding acquisition: E.-A.J. All authors have read and agreed to the published version of the manuscript.

Funding

This research was commissioned by the Ministry of Environment and Tourism of Mongolia and funded by the Mongolian Science and Technology Foundation, Project Agreement No. ShuUz_2020/01.

Institutional Review Board Statement

Not applicable.

Data Availability Statement

Data are contained within the article.

Acknowledgments

The authors thank Gundegmaa Vanjil for plant authentication, Galbadrakh Ayush for his help in sampling medicinal plants, and Lkhagvadorj Lodonsharav for safe and comfortable driving.

Conflicts of Interest

The authors declare no conflict of interest.

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Figure 1. Habitat of the collected plant samples. Cynomorium songaricum (A) growing in sandy soil, and rhizome of Cynomorium songaricum on the root of the host plant Nitraria sibirica Pall. (B).
Figure 1. Habitat of the collected plant samples. Cynomorium songaricum (A) growing in sandy soil, and rhizome of Cynomorium songaricum on the root of the host plant Nitraria sibirica Pall. (B).
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Figure 2. The morphological diversity of endophytic fungi isolated from Cynomorium songaricum.
Figure 2. The morphological diversity of endophytic fungi isolated from Cynomorium songaricum.
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Figure 3. Production of IAA by endophytic fungal strains.
Figure 3. Production of IAA by endophytic fungal strains.
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Figure 4. Phosphate and zinc solubilization by endophytic fungal strains.
Figure 4. Phosphate and zinc solubilization by endophytic fungal strains.
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Table 1. Closest relatives of endophytic fungal strains Based on ITS sequence BLAST analyses.
Table 1. Closest relatives of endophytic fungal strains Based on ITS sequence BLAST analyses.
StrainAccession NoPlant PartSpecies with Most Homologous Sequence (Accession No) Similarity %
P26-H1-1LC769420AbovegroundFusarium equiseti CB33-4
(MT558601)		99.81
P26-H1-3LC769421AbovegroundClonostachys rosea MR44
(KY320599)		99.65
P26-H2-1LC769422AbovegroundFusarium solani GBC-Fungus 27
(MN077430)		100
P26-H2-2LC769423AbovegroundFusarium solani N-49-1
(MT560378)		100
P26-R1-1LC769424UndergroundFusarium equiseti NL-374-D
(OQ561206)		99.63
P26-R1-3LC769425UndergroundAlternaria sp. INM5
(KY781740)		99.30
P26-R2-1LC769426UndergroundFusarium solani N-13-2
(MT560338)		100
P26-R2-2LC769427UndergroundClonostachys rosea MR44
(KY320599)		99.13
P26-ZN1-1LC769428Fresh rhizomePenicillium chrysogenum MZC-0
(MN069559) 		99.66
P26-ZN1-2LC769429Fresh rhizomeMadurella fahalii 332- pus
(OQ421454)		98.96
P26-ZN1-3LC769430Fresh rhizomeAspergillus tabacinus fung8
(MT635280)		100
P26-ZN2-2LC769431Fresh rhizomePenicillium chrysogenum MZC-0 (MN069559) 99.83
P26-ZN2-3LC769432Fresh rhizomePenicillium roseopurpureum IHEM:28005 (OU989457)99.83
P26-ZN2-4LC769433Fresh rhizomeFusarium sp. GFR18
(MT447523) 		100
P26-ZN2-5LC769434Fresh rhizomePenicillium vinaceum 533
(DQ681340)		100
P26-ZN2-6LC769435Fresh rhizomePenicillium roseopurpureum G5-2 (MN206951)100
P26-ZO1-1LC769436Old rhizomePenicillium sp. FP-027-A7
(MH102087)		99.49
P26-ZO1-3LC769437Old rhizomeClonostachys rosea daef27
(MH550497)		99.12
P26-ZO1-4LC663164Old rhizomeClonostachys rosea Potato root
(MT448899)		100
P26-ZO1-5LC769438Old rhizomeClonostachys sp. 1R1D
(OR365747) 		99.82
P26-ZO1-6LC769439Old rhizomeFusarium sp. GFR18
(MT447523) 		99.82
P26-ZO2-1LC769440Old rhizomeFusarium proliferatum CBB-6
(MT560216)		100
P26-ZO2-2LC769441Old rhizomeClonostachys rosea MR44
(KY320599)		99.83
P26-ZO2-3LC769442Old rhizomeClonostachys rosea N25
(MH259861)		100
Table 2. Antimicrobial activity of endophytic fungi.
Table 2. Antimicrobial activity of endophytic fungi.
StrainTaxaDiameter of the Inhibitory Zone (mm)
Escherichia coliBacillus subtilisStaphylococcus aureusCandida albicansAspergillus niger
P26-H1-1Fusarium equiseti-15.5 ± 0.712 ± 0--
P26-H1-3Clonostachys rosea-10.5 ± 0.7--15.5 ± 0.7
P26-H2-1Fusarium proliferatum-11.5 ± 1.413 ± 0.7--
P26-H2-2Fusarium solani--10.5 ± 0.7-23 ± 2.8
P26-R1-1Fusarium equiseti-15.5 ± 0.713.5 ± 0.7--
P26-R2-1Fusarium solani----22.5 ± 0.7
P26-R2-2Clonostachys rosea--7.5 ± 2.1--
P26-ZN1-2Madurella fahalii7.5 ± 0.79.5 ± 2.115.5 ± 0.7--
P26-ZN1-3Aspergillus amoenus-8 ± 1.47 ± 0--
P26-ZO1-3Clonostachys rosea-15 ± 018.5 ± 0.7-13.5 ± 2.1
P26-ZO1-4Clonostachys rosea-9 ± 4.29.5 ± 0.7-12.5 ± 2.1
P26-ZO1-5Clonostachys rosea-13.5 ± 0.716.5 ± 0.7-14 ± 1.4
P26-ZO1-6Fusarium tonkinense-11.5 ± 0.717.5 ± 0.7-12 ± 0
P26-ZO2-2Clonostachys rosea-12 ± 015.5 ± 2.1--
P26-ZO2-3Clonostachys rosea-13.5 ± 0.716 ± 0-13 ± 1.4
Note: -: no inhibitory activity.
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Jigjiddorj, E.-A.; Maidarjav, A.; Byambasuren, B.; Nyamgerel, D. Identification, Antimicrobial and Plant Growth Promoting Activities of Endophytic Fungi Associated with Cynomorium songaricum Rupr., a Traditional Medicinal Plant in Mongolia. Diversity 2024, 16, 122. https://doi.org/10.3390/d16020122

AMA Style

Jigjiddorj E-A, Maidarjav A, Byambasuren B, Nyamgerel D. Identification, Antimicrobial and Plant Growth Promoting Activities of Endophytic Fungi Associated with Cynomorium songaricum Rupr., a Traditional Medicinal Plant in Mongolia. Diversity. 2024; 16(2):122. https://doi.org/10.3390/d16020122

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Jigjiddorj, Enkh-Amgalan, Amarbayasgalan Maidarjav, Bumtsend Byambasuren, and Daritsogzol Nyamgerel. 2024. "Identification, Antimicrobial and Plant Growth Promoting Activities of Endophytic Fungi Associated with Cynomorium songaricum Rupr., a Traditional Medicinal Plant in Mongolia" Diversity 16, no. 2: 122. https://doi.org/10.3390/d16020122

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