Diversity Of Fungal Endophytes Research Articles

Diversity and abundance of culturable fungal endophytes in leaves of susceptible and resistant alternate hosts of Cronartium pini and C. ribicola

Diversity and abundance of culturable fungal endophytes in leaves of susceptible and resistant alternate hosts of Cronartium pini and C. ribicola

Diversity and seasonal variation of fungal endophytes associated with Ageratum conyzoides L.: an invasive species

Diversity and seasonal variation of fungal endophytes associated with Ageratum conyzoides L.: an invasive species

Genetic Diversity of Fungal Endophytes

Genetic Diversity of Fungal Endophytes

Abundance and diversity of fungal endophytes isolated from monk fruit (Siraitia grosvenorii) grown in a Canadian research greenhouse.

Monk fruit (Siraitia grosvenorii) is an herbaceous perennial vine of the Cucurbitaceae family cultivated commercially mainly in southern China. There is very little information available about the fungal endophytes in monk fruit. In this study, monk fruit plants were grown from seeds in a research greenhouse at Kwantlen Polytechnic University in British Columbia, Canada to explore the abundance and diversity of their fungal endophytes. Fungal endophytes were isolated from seeds, seedlings, mature monk fruit plants, and fruits, and cultured on potato dextrose agar and water agar media. Isolates were identified by microscopic examination and BLAST comparison of ITS sequences to published sequences in GenBank. At least 150 species of fungal endophytes representing 60 genera and 20 orders were recovered from monk fruit tissues. Non-metric multidimensional scaling (NMDS) was carried out to explore the similarity of fungal communities among roots, stems, leaves, flowers, fruits, and seeds based on fungal orders. Our study showed that monk fruit plants are a rich source of fungal endophytes with the greatest abundance and diversity in leaves. This work has deepened our understanding of the intricate interactions between plants and fungi that sustain ecosystems and underpin plant health and resilience.

Diversity of Leaf Fungal Endophytes from Two Coffea arabica Varieties and Antagonism towards Coffee Leaf Rust.

Coffee has immense value as a worldwide-appreciated commodity. However, its production faces the effects of climate change and the spread of severe diseases such as coffee leaf rust (CLR). The exploration of fungal endophytes associated with Coffea sp. has already found the existence of nearly 600 fungal species, but their role in the plants remains practically unknown. We have researched the diversity of leaf fungal endophytes in two Coffea arabica varieties: one susceptible and one resistant to CLR. Then, we conducted cross-infection essays with four common endophyte species (three Colletotrichum sp. and Xylaria sp. 1) and Hemileia vastatrix (CLR) in leaf discs, to investigate the interaction of the endophytes on CLR colonisation success and severity of infection. Two Colletotrichum sp., when inoculated 72 h before H. vastatrix, prevented the colonisation of the leaf disc by the latter. Moreover, the presence of endophytes prior to the arrival of H. vastatrix ameliorated the severity of CLR. Our work highlights both the importance of characterising the hidden biodiversity of endophytes and investigating their potential roles in the plant-endophyte interaction.

Environmental drivers and cryptic biodiversity hotspots define endophytes in Earth’s largest terrestrial biome

Understanding how symbiotic associations differ across environmental gradients is key to predicting the fate of symbioses as environments change, and it is vital for detecting global reservoirs of symbiont biodiversity in a changing world.1,2,3 However, sampling of symbiotic partners at the full-biome scale is difficult and rare. As Earth's largest terrestrial biome, boreal forests influence carbon dynamics and climate regulation at a planetary scale. Plants and lichens in this biome host the highest known phylogenetic diversity of fungal endophytes, which occur within healthy photosynthetic tissues and can influence hosts' resilience to stress.4,5 We examined how communities of endophytes are structured across the climate gradient of the boreal biome, focusing on the dominant plant and lichen species occurring across the entire south-to-north span of the boreal zone in eastern North America. Although often invoked for understanding the distribution of biodiversity, neither a latitudinal gradient nor mid-domain effect5,6,7 can explain variation in endophyte diversity at this trans-biome scale. Instead, analyses considering shifts in forest characteristics, Picea biomass and age, and nutrients in host tissues from 46° to 58° N reveal strong and distinctive signatures of climate in defining endophyte assemblages in each host lineage. Host breadth of endophytes varies with climate factors, and biodiversity hotspots can be identified at plant-community transitions across the boreal zone at a global scale. Placed against a backdrop of global circumboreal sampling,4 our study reveals the sensitivity of endophytic fungi, their reservoirs of biodiversity, and their important symbiotic associations, to climate.

Diversity of fungal endophytes from mangrove plants of Santa Catarina Island, Brazil.

The mangrove ecosystem plays a crucial role in preserving the biodiversity of plants, animals, and microorganisms that are essential for materials cycles. However, the exploration of endophytic fungi isolated from mangroves, particulary in Santa Catarina (SC, Brazil), remains limited. Therefore, the purpose of this study was to assess the biodiversity of endophytic fungi found in Avicennia schaueriana, Laguncularia racemosa, Rhizophora mangle, and Spartina alterniflora from two mangroves on the Island of Santa Catarina: one impacted by anthropic action (Itacorubi mangrove) and the other environmentally preserved (Ratones mangrove). Samplings were carried out between January 2020 and May 2021. Fungi were isolated from leaves, stems, and roots, identified, and clustered into groups through morphological characteristics. Further, a representative strain of each group was identified through ITS1 sequencing. A total of 373 isolates were obtained from plant tissues, of which 96 and 277 isolates were obtained from Itacorubi and Ratones mangroves, respectively. Molecular identification showed that the endophytic fungal community comprised at least 19 genera. The data on fungal community diversity revealed comparable diversity indices for genera in both mangroves. However, we observed differences in the total frequency of fungal genera between impacted (27.38%) and non-impacted (72.62%) mangroves. These findings suggest that anthropic activities in and around the Santa Catarina mangroves have had negative impact on the frequency of endophytic fungi. This emphasizes the reinforcing the significance of preserving these environments to ensure the maintenance of fungal community diversity.

Comparative Diversity and Functional Traits of Fungal Endophytes in Response to Elevated Mineral Content in a Mangrove Ecosystem.

This study investigates the impact of water quality, specifically elevated phosphate and zinc content, on the diversity and functional properties of mangrove fungal endophytes in two distinct mangrove forests. Mangrove plant performance is directly related to the presence of fungal leaf endophytes as these fungi could enhance plant health, resilience, and adaptability under stressed environmental conditions. Two distinct mangrove forest sites, one non-disturbed (ND) and one disturbed by aquaculture practices (D), were assessed for differences in water quality parameters. We further analyzed the fungal endophyte diversity associated with the leaves of a target host mangrove, Rhizophora mucronata Lamk., with the aim to elucidate whether fungal diversity and functional traits are linked to disturbances brought about by aquaculture practices and to characterize functional traits of selected fungal isolates with respect to phosphate (PO4) and zinc (Zn) solubilization. Contrary to expectations, the disturbed site exhibited a higher fungal diversity, challenging assumptions about the relationship between contamination and fungal community dynamics. Water quality, as determined by nutrient and mineral levels, emerged as a crucial factor in shaping both microbial community compositions in the phyllosphere of mangroves. From both sites, we isolated 188 fungal endophytes, with the ND site hosting a higher number of isolates and a greater colonization rate. While taxonomic diversity marginally differed (ND: 28 species, D: 29 species), the Shannon (H' = 3.19) and FAI (FA = 20.86) indices revealed a statistically significant increase in species diversity for fungal endophytes in the disturbed mangrove site as compared to the non-disturbed area (H' = 3.10, FAI = 13.08). Our chosen mangrove fungal endophytes exhibited remarkable phosphate solubilization capabilities even at elevated concentrations, particularly those derived from the disturbed site. Despite their proficiency in solubilizing zinc across a wide range of concentrations, a significant impact on their mycelial growth was noted, underscoring a crucial aspect of their functional dynamics. Our findings revealed a nuanced trade-off between mycelial growth and enzymatic production in fungal endophytes from ostensibly less contaminated sites, highlighting the relationship between nutrient availability and microbial activities. These insights provide a foundation for understanding the impact of anthropogenic pressures, specifically nutrient pollution, on mangrove-associated fungal endophytes.

Diversity of fungal endophytes isolated from the invasive plant Solanum rostratum

A culture-dependent method was used to isolate fungal endophytes from the leaves, stems, and roots of the invasive plant Solanum rostratum Dunal. growing in Xinjiang Province, China. All isolates were identified according to ITS (internal transcribed spacer) region of ribosomal DNA sequences and analyzed by Nucleotide BLAST according to NCBI GenBank and Mycobank database. Altogether 176 endophytic fungal isolates corresponding to 44 OTUs were identified, which were classified into 12 genera, with Penicillium (59.66%) and Aspergillus (23.29%) being the highly dominant genera. Ten endophytic isolates (OTU1, OTU15, OTU16, OTU21, OTU23, OTU25, OTU26, OTU30, OTU37 and OTU44) were identified as potential new species.

Seasonal diversity & spaciotemporal distribution of fungal endophytes associated with the medicinal plant Coleus forskohlii Briq.

Fungi that colonize the healthy tissues of the plants without showing any disease symptoms in the host plants are termed as fungal endophytes. The presence of fungal endophytes provides a positive effect on the host’s growth & development and also triggers the production of some essential bioactive compounds in the host. This study was undertaken to isolate, identify and understand the spaciotemporal distribution and seasonal diversity of fungal endophytes associated with the leaf, stem & root of Coleus forskohlii, an important and endangered medicinal plant. Sampling was done for a period of 12 months between May 2020–April 2021. A total of 950 fungal endophytes were isolated from a total of 1680 tissues of the leaf, stem & root of C. forskohlii. The fungi were identified based on their morphological features and some of them were identified by molecular identification by 18S rRNA sequencing. The endophytic isolates belonged to 10 different orders belonging to 3 different classes-Sordariomycetes (Hypocreales, Xylariales, Microascales, Trichosphaeriales, Glomerellales & Sordariales), Dothiomycetes (Pleosporales, Capnodiales, Botryosphaeriales) & Eurotiomyctes (Eurotiales). About 81.26% of the isolates belonged to Ascomycota & 2.63% of the isolates belonged to Mucoromycota. Chaetomium globosum, Collariella bostrychodes, C. robusta, Colletotrichum gloeosporioides, Fusarium chlamydosporum, Sterile hyaline mycelia, Aspergillus niger, Xylaria curta, X. grammica, Mucor circinelloides & Trichoderma harizianum were the frequently isolated species of fungi. C. globosum, C. bostrychodes, C. gloeosporioides, sterile hyaline mycelia & X. curta were found distributed in all the tissues of the plant. C. forskohlii has thus revealed a rich diversity of fungal endophytes that could be isolated & cultured to yield some pharmacologically important bioactive compounds.

Endophytic fungal community of Rosa damascena Mill. as a promising source of indigenous biostimulants: Elucidating its spatial distribution, chemical diversity, and ecological functions

The role of endophytes in maintaining healthy plant ecosystems and holding promise for agriculture and food security is deeply appreciated. In the current study, we determine the community structure, spatial distribution, chemical diversity, and ecological functions of fungal endophytes of Rosa damascena growing in the North-Western Himalayas. Culture-dependent methods revealed that R. damascena supported a rich endophyte diversity comprising 32 genera and 68 OTUs. The diversity was governed by climate, altitude, and tissue type. Species of Aspergillus, Cladosporium, Penicillium, and Diaporthe were the core endophytes of the host plant consisting of 48.8% of the endophytes collectively. The predominant pathogen of the host was Alternaria spp., especially A. alternata. GC-MS analyses affirmed the production of diverse arrays of volatile organic compounds (VOC) by individual endophytes. Among the primary rose oil components, Diaporthe melonis RDE257, and Periconia verrucosa RDE85 produced phenyl ethyl alcohol (PEA) and benzyl alcohol (BA). The endophytes displayed varied levels of plant growth-promoting, colonization, and anti-pathogenic traits. Between the selected endophytes, P. verrucosa and D. melonis significantly potentiated plant growth and the flavonoids and chlorophyll content in the host. The potential of these two endophytes and their metabolites PEA and BA was confirmed on Nicotiana tabacum. The treatments of the metabolites and individual endophytes enhanced the growth parameters in the model plant significantly. The results imply that P. verrucosa and D. melonis are potential plant growth enhancers and their activity may be partially due to the production of PEA and BA. Thus, R. damascena harbors diverse endophytes with potential applications in disease suppression and host growth promotion. Further investigations at the molecular level are warranted to develop green endophytic agents for sustainable cultivation of R. damascena and biocontrol of leaf spot disease.

Insights into diversity and L-asparaginase activity of fungal endophytes associated with medicinal plant Grewia hirsuta.

L-asparaginase is used as one of the prime chemotherapeutic agents to treat acute lymphoblastic leukemia. The present work aimed to study the endophytic fungal diversity of Grewia hirsuta and their ability to produce L-asparaginase. A total of 1575 culturable fungal endophytes belonging to four classes, Agaricomycetes, Dothideomycetes, Eurotiomycetes, and Sordariomycetes, were isolated. The isolates were grouped into twenty-one morphotypes based on their morphological characteristics. Representative species from each group were identified based on their microscopic characteristics and evaluation of the ITS and LSU rDNA sequences. Most of the fungal endophytes were recovered from the leaves compared to other plant parts. Diaporthe sp. was the predominant genus with a colonization frequency of 8.62%. Shannon-Wiener index for diversity ranged from 2.74 to 2.88. All the plant parts showed similar Simpson's index values, indicating a uniform species diversity. Among the sixty-three fungal endophytes screened, thirty-two were identified as L-asparaginase-producing isolates. The enzyme activities of fungal endophytes estimated by the nesslerization method were found to be in the range of 4.65-0.27 IU/mL with Fusarium foetens showing maximum enzyme activity of 4.65 IU/mL. This study for the first time advocates the production of L-asparaginase from Fusarium foetens along with the endophytic fungal community composition of Grewia hirsuta. The results indicate that the fungal endophyte Fusarium foetens isolated in the present study could be a potent source of L-asparaginase.

The Influence of Cone Age and Urbanisation on the Diversity and Community Composition of Culturable Seed Fungal Endophytes within Native Australian Banksia ericifolia L.f. subsp. ericifolia.

Seed fungal endophytes play a crucial role in assisting the overall health and success of their host plant; however, little is known about the factors that influence the diversity and composition of these endophytes, particularly with respect to how they change over time and within urban environments. Using culturing techniques, morphological analyses, and Sanger sequencing, we identified the culturable seed fungal endophytes of Banksia ericifolia at two urban and two natural sites in Sydney, New South Wales, Australia. A total of 27 Operational Taxonomic Units were obtained from 1200 seeds. Older cones were found to contain, on average, more colonised endophytes than younger cones. Species richness was also significantly influenced by cone age, with older cones being more speciose. Between urban and natural sites, the overall community composition did not change, although species richness and diversity were greatest at urban sites. Understanding how these endophytes vary in time and space may help provide an insight into the transmission pathways used and the potential role they play within the development and survival of the seed. This knowledge may also be crucial for restoration purposes, especially regarding the need to consider endophyte viability in ex situ seed collection and storage in seed-banking practices.

Hierarchical metacommunity structure of fungal endophytes.

The ecological and evolutionary processes shaping community structure and functions of microbial symbionts are known to be scale-dependent. Nonetheless, understanding how the relative importance of these processes changes across spatial scales, and deciphering the hierarchical metacommunity structure of fungal endophytes has proven challenging. We investigated metacommunities of endophytic fungi within leaves of an invasive plant (Alternanthera philoxeroides) across wide latitudinal transects both in its native (Argentina) and introduced (China) ranges to test whether metacommunities of fungal endophytes were structured by different drivers at different spatial scales. We found Clementsian structures with seven discrete compartments (distinctive groups of fungal species with coincident distribution ranges), which coincided with the distribution of major watersheds. Metacommunity compartments were explicitly demarcated at three spatial scales, that is, the between-continent, between-compartment, and within-compartment scales. At larger spatial scales, local environmental conditions (climate, soil, and host plant traits) were replaced by other geographical factors as principal determinants of metacommunity structure of fungal endophytes and community diversity-function relationships. Our results reveal novel insights into the scale dependency of diversity and functions of fungal endophytes, which are likely similar for plant symbionts. These findings can potentially improve our understanding of the global patterns of fungal diversity.

Taxonomic analysis reveals host preference of rare fungi in endophytes of Vitis vinifera from the Czech Republic.

This paper represents the results of screening a diversity of fungal endophytes associated with Vitis vinifera leaves and canes in the Czech Republic. The characterization of strains is based on morphological and phylogenetic analyses of ITS, EF1α and TUB2 sequence data. Our strain selection covers 16 species and seven orders belonging to Ascomycota and Basidiomycota. Together with ubiquitous fungi, we report on several poorly known plant-associated fungi, Angustimassarina quercicola (= A. coryli, a synonym proposed in this study) and Pleurophoma pleurospora. Other species, such as Didymella negriana, D. variabilis, Neosetophoma sp. (species identical or sister to N. rosae), Phragmocamarosporium qujingensis and Sporocadus rosigena, have so far been little known and rarely found, but are frequent on V. vinifera in different parts of the world and obviously belong to a microbiota with a strong preference for this plant. Detailed taxonomical identification allowed us to identify species with apparent stable associations with V. vinifera, for which further interactions with V. vinifera can be expected. Our study is the first to focus on V. vinifera endophytes in Central Europe and expands the knowledge about their taxonomy, ecology and geography.

Diversity of fungal endophytes at different maturity levels of Cryptolepis buchanani leaves

A study on endophytic microflora diversity at each level and portion of the leaves of Cryptolepis buchanani, a medicinal plant used by tribals of Madhya Pradesh, India was carried out in the present investigation. As many as 383 isolates from 360 discs of leaves belonging to 17 fungal species and 9 isolates, which did not show any sporulation (sterile), were recovered. Among the 17 identified species, hyphomycetes is the dominant class and Aspergillus, Colletotrichum and Khuskia are the dominant genera. Colonization frequency (CF) was higher in mature leaves (78.3%) and comparatively lower in younger leaves (51.1%) and there was a marginal decrease in CF from the base of the leaf (66.7%) towards the leaf apex (62%). Statistical analysis revealed that level of the leaf had a significant effect on CF and diversity of fungal endophytes, while as leaf sub-parts had little influence. Biochemical characterization of the endophyte revealed the production of various enzymes viz. protease, amylase, lipase, cellulase, xylanase and pectinase. These fungal enzymes can be tapped for food, pharma, beverages, textiles, confectionaries, and leather industries. These bioactive natural products are easy to process as they are usually more stable than products obtained from other sources. The enzymatic activities also help to get a better insight into the host-endophyte relationship. However, the world of fungal endophytes needs to be researched extensively for production of plant based novel eco-friendly biomolecules in cost-effective manner.

Antimicrobial and antioxidant potentials of crude extracts of culturally dissimilar endophytic fungi

Endophytes from an unexplored plant such as Spatterdock (SD) Nuphar lutea variegata could be a dependable producer of novel secondary metabolites active against drug resistance organisms. This study explored the diversity of fungal endophytes from mid-rib (MR) and leaf blade (LB) of Nuphar lutea variegata as well as the antimicrobial and antioxidant potentials of their secondary metabolites. Morphological features observed showed four species were isolated. A broad-spectrum antimicrobial activity observed to be concentration-dependent was observed for all the fungal crude extracts 1 mg/mL. Crude extract of SD-LB3 showed the best antibacterial activities against S. aureus and P. aeruginosa with a minimum inhibitory concentration of 0.5 and 0.25 µg/mL respectively. The antioxidant capacities of the fungal crude extracts showed a better neutralizing effect of free radicals compared to the standard Quercitin. Effective inhibition of free radicals was observed for all the fungal extracts from 20 to 100 mg/mL (96.7 – 99.3 %). The highest antioxidant activity was shown by the extracts of fungi isolated from the leaf blade with an average of 98 to 99.2 % at the tested concentrations of 20 to 100 mg/mL. Our study provides evidence of diverse endophytic fungi associated with Nuphar lutea variegata, and the antibacterial and antioxidant activities observed confirm their capacities as producers of bioactive secondary metabolites. This study is the first to isolate endophytic fungi form Nuphar lutea variegata and screen the antimicrobial and antioxidant activities of their secondary metabolites.

Diversity of Fungal Endophytes in American Ginseng Seeds.

Seeds play a critical role in the production of American ginseng. Seeds are also one of the most important media for the long-distant dissemination and the crucial way for pathogen survival. Figuring out the pathogens carried by seeds is the basis for effective management of seedborne diseases. In this paper, we tested the fungi carried by the seeds of American ginseng from the main production areas of China using incubation and highly throughput sequencing methods. The seed-carried rates of fungi in Liuba, Fusong, Rongcheng, and Wendeng were 100, 93.8, 75.2, and 45.7%, respectively. Sixty-seven fungal species, which belonged to 28 genera, were isolated from the seeds. Eleven pathogens were identified from the seed samples. Among the pathogens, Fusarium spp. were found in all of the seed samples. The relative abundance of Fusarium spp. in the kernel was higher than that in the shell. Alpha index showed that the fungal diversity between seed shell and kernel differed significantly. Nonmetric multidimensional scaling analysis revealed that the samples from different provinces and between seed shell and kernel were distinctly separated. The inhibition rates of four fungicides to seed-carried fungi of American ginseng were 71.83% for Tebuconazole SC, 46.67% for Azoxystrobin SC, 46.08% for Fludioxonil WP, and 11.11% for Phenamacril SC. Fludioxonil, a conventional seed treatment agent, showed a low inhibitory effect on seed-carried fungi of American ginseng.

Molecular characterization of fungal endophyte diversity isolated from Aconitum heterophyllum: a critically endangered medicinal plant of Kashmir Himalaya.

Aconitum heterophyllum is a rare perennial herb from Kashmir Himalayas. Due to its threatened status and dependence on its environment, the plant was examined for any potential endophytes, which is of utmost importance for bioprospection. In the current study, endophytic fungal diversity associated with A. heterophyllum was examined, and 328 fungal isolates were found in the plant's leaf, stem, and root tissues. Twelve (12) endophytic fungal species were identified utilizing, molecular analysis of the nuclear ribosomal DNA Internal Transcribes Spacer (ITS), rLSU, and rSSU sequences. Maximum likelihood analysis was used to determine the phylogenetic connection between each isolate. The genera Arthrinium, Chaetomium, Purpureocillium, Alternaria, Penicillium, Aspergillus, Cladosporium, and Bjerkandera species dominated the ascomycete and basidiomycete fungal endophytes.

Molecular Identification of Fungal Endophytes of Medicinal Plant Citrullus colocynthis (L.) Schrad as a Medicinal Plant: Role of Tissue Type and Sampling Location on the Diversity.

Endophytic fungi are an important group of organisms in association with plants which are able to colonize all plant internal tissues and improve their fitness. The present research aims to isolate and identify endophytic fungi of Citrullus colocynthis plant and then investigate the effects of sampling location and tissue type on the fungal endophyte diversity of this plant. To do so, a sampling program was done in 11 geographically isolated C. colocynthis growing areas of Hormozgan province, Iran. For molecular identification of endophytic fungi of C. colocynthis, the internal transcribed spacer region (ITS1-5.8S-ITS4), as a universal DNA barcode marker for fungi, was amplified using primer sets. Totally, 12 taxa (Alternaria solani, Cladosporium halotolerans, Setosphaeria rostrata, Aspergillus niger, A. allahabadii, A. terreus, A. occultus, A. cristatus, Penicillium chrysogenum, Talaromyces purpureogenus, Fusarium sp., and Pseudozyma flocculosa) were isolated. Our findings also showed that the diversity of fungal endophytes isolated from C. colocynthis was affected by the tissue type and sampling site. Accordingly, the leaves and seeds were found to have the highest and lowest rates of endophyte colonization and richness in all sampling seasons, respectively. Simpson's diversity index of 0.8165 in root tissue indicated the high diversity of endophytes in this organ. In addition, Shannon's diversity index in the root (1.846) was higher than that in the other organs. The highest Shannon's and Simpson's indices were observed in Khoon Sorkh and Minab regions. Generally, at least two factors (region and type of tissue) played the most important roles in determining the composition of fungal endophytes in C. colocynthis.