Endophytic Species Research Articles

Distribution and characterization of endophytic and rhizosphere bacteriome of below-ground tissues in Chinese fir plantation.

None declared.Conflict of interestPlantation of Chinese fir, a popular woody tree species, faces sustainable issues such as nutrient deficiency and increasing disease threat. Rhizosphere and endophytic bacteria play important roles in plant' nutrient absorption and stress alleviation. Our understanding on the microbiome structure and functions are proceeding rapidly in model plants and some crop species. Yet, the spatial distribution and functional patterns of the bacteriome for the woody trees remain largely unexplored. In this study, we collected rhizosphere soil, non-rhizosphere soil, fine root, thick root and primary root samples of Chinese fir, and investigated the structure and distribution of bacteriome, as well as the beneficial effects of endophytic bacterial isolates. We discovered that Burkholderia and Paraburkholderia genera were overwhelmingly enriched in rhizosphere soil and the abundance of Pseudomonas genus was significantly enhanced in fine root. By isolating and testing the nutrient absorption and pathogen antagonism functions of representative endophytic bacteria species in Pseudomonas and Burkholderia, we noticed that P-solubilising functional isolates was enriched in fine root, while pathogen antagonism isolates was enriched in thick root. As a conclusion, our study revealed that the endophytic and rhizosphere environments of Chinese fir hold distinct structure and abundance of bacteriome, with potential specific functional enrichment of some bacterial clades. These findings assist us to further study the potential regulation mechanism of endophytic functional bacteria by the host tree, which will contribute to beneficial microbe application in forestry plantation and sustainable development.

Cytospora anacardii (Cytosporaceae, Diaporthales): A new endophytic species from Anacardium occidentale of the Brazilian savanna

Cytospora species are mainly found as phytopathogens but are also reported as endophytes and saprophytes in several host plants. During a study of the diversity of endophytic fungi associated with Anacardium occidentale in an area of the Brazilian savanna (Cerrado), isolates of Cytospora were identified and differentiated from other species by morphological and phylogenetic analyses (ITS, act, rpb2, tef1, and tub2). Cytospora anacardii has been proposed as a new endophytic species, and it has pycnidia and conidiogenous cells smaller than those of the phylogenetically related species Cytospora phitsanulokensis. Our data highlight the importance of investigating endophytes as important economic hosts and expand our knowledge of global Cytospora diversity and distribution. To the best of our knowledge, this is the first report of Cytospora being an endophyte of Anacardium occidentale.

Five new species of endophytic Penicillium from rubber trees in the Brazilian Amazon.

The Amazon rainforest is the world's most diverse ecosystem, full of fauna and flora. Among the trees that make up the forest are the rubber trees of the genus Hevea (H. brasiliensis and H. guianensis), which stand out for the industrial use of latex. It was previously shown that endophytic fungi colonize the leaves, stems, and roots of Hevea spp. In this study, 47 Penicillium spp. and three Talaromyces spp. isolates were analyzed using specific DNA barcodes: internal transcribed spacers region (ITS), β-tubulin (BenA), calmodulin (CaM), and the DNA-dependent RNA polymerase II second largest subunit (RPB2) genes and additionally, for species delimitation, the genealogical concordance phylogenetic species recognition (GCPSR) criteria were applied. The phylogenetic analyses placed the Penicillium isolates into four sections Lanata-Divaricata, Sclerotiora, Citrina, and Fasciculata. The morphological and molecular characteristics resulted in the discovery of five new species (P. heveae sp. nov., P. acrean sp. nov., P. aquiri sp. nov., P. amazonense sp. nov., and P. pseudomellis sp. nov.). The five new species were also compared to closely related species, with observations on morphologically distinguishing features and colony appearances. Bayesian inference and maximum likelihood analysis have supported the placement of P. heveae sp. nov. as a sister group to P. globosum; P. acrean sp. nov. and P. aquiri sp. nov. as sister groups to P. sumatrense; P. amazonense sp. nov. closely related to isolates of P. rolfsii, and P. pseudomellis sp. nov. closely related to P. mellis. The study of endophytic Penicillium species of rubber trees and the description of five new taxa of Penicillium sect. Citrina, Lanata-Divaricata, and Sclerotiora as endophytes add to the fungal biodiversity knowledge in native rubber trees. Reports of fungi in native tropical plants may reveal taxonomic novelties, potential pathogen control agents, and producers of molecular bioactive compounds of medical and agronomic interest.

Harnessing Endophytic Fungi from Terminalia chebula: A Dual Approach to Antimicrobial and Phytochemical Exploration

Endophytic fungi isolated from Terminalia chebula exhibit potent antimicrobial activity, showcasing their potential to develop novel therapeutic agents. Additionally, these fungi produce diverse phytochemicals, which may contribute to their medicinal properties and offer new avenues for natural product research. This research study investigated the endophytic fungi isolated from T. chebula and assessed their antimicrobial and phytochemical potential. A total of 28 endophytic fungal species were isolated from leaf and bark tissues. Antimicrobial assays revealed significant inhibitory effects against pathogenic fungi Candida albicans - MTCC 183 & Saccharomyces cerevisiae - MTCC 174 and bacteria Escherichia coli - MTCC 2939, & Bacillus subtilis - MTCC 1305, with endophytic Alternaria sp. exhibiting maximum inhibition zone for antifungal activity and endophytic Aspergillus flavus demonstrating potent activity for their antibacterial analysis. A wide array of phytochemical compounds like alkaloids, flavonoids, phenols, steroids, terpenoids, tannin, saponin, etc, were observed whereas, phytochemical screening indicated the presence of alkaloids and flavonoids in all selected endophytes. These findings suggest that T. chebula harbors a rich endophytic community with the potential for producing novel antimicrobial compounds.

Community structure, diversity and function of endophytic and soil microorganisms in boreal forest.

Despite extensive studies on soil microbial community structure and functions, the significance of plant-associated microorganisms, especially endophytes, has been overlooked. To comprehensively anticipate future changes in forest ecosystem function under future climate change scenarios, it is imperative to gain a thorough understanding of the community structure, diversity, and function of both plant-associated microorganisms and soil microorganisms. In our study, we aimed to elucidate the structure, diversity, and function of leaf endophytes, root endophytes, rhizosphere, and soil microbial communities in boreal forest. The microbial structure and composition were determined by high-throughput sequencing. FAPROTAX and FUNGuild were used to analyze the microbial functional groups. Our findings revealed significant differences in the community structure and diversity of fungi and bacteria across leaves, roots, rhizosphere, and soil. Notably, we observed that the endophytic fungal or bacterial communities associated with plants comprised many species distinct from those found in the soil microbial communities, challenging the assumption that most of endophytic fungal or bacterial species in plants originate from the soil. Furthermore, our results indicated noteworthy differences in the composition functional groups of bacteria or fungi in leaf endophytes, root endophytes, rhizosphere, and soil, suggesting distinct roles played by microbial communities in plants and soil. These findings underscore the importance of recognizing the diverse functions performed by microbial communities in both plant and soil environments. In conclusion, our study emphasizes the necessity of a comprehensive understanding of the structure and function microbial communities in both plants and soil for assessing the functions of boreal forest ecosystems.

Influence of endophytic fungi treatments on aluminum contents in Vernicia montana seedlings and soils under different concentrations of aluminum stress

Although leveraging the interaction with endophytic fungi is an efficient and environment-friendly strategy for plants to enhance growth and resistance, how different endophyte species influence host plants’ resilience in adverse conditions remain comparatively unclear. In order to explore the effect of endophytic fungi on the aluminum resistance of woody host plants, Vernicia montana seedlings were subjected to different aluminum concentrations (T0, T1, T2, T3, T4) in this study. The aluminum contents in roots, leaves and rhizospheric soil of V. montana seedlings were determined after applying endophyte suspensions of Pestalotiopsis (NP), Alternaria (LA), Penicillium (QP), Coniothyrium (DC) and Thermophilic (ST) spp. The results showed that aluminum stress treatment, endophytic fungi treatment and their interaction had significant effects on aluminum content in leaves, aluminum content in roots, aluminum content in rhizospheric soil, and the transport and retention rate of aluminum ions in soil-root-leaf. With the increase of aluminum concentrations, the aluminum content in leaves of V. montana increased in the endophyte treatments of LA and ST, decreased in CK, NP and DC, or had marginal variation in QP treatment. Compared with T0, four endophyte treatments of LA, QP, DC and ST significantly reduced root aluminum content under T4 concentration (P < 0.05), contrary to the results of NP treatment. Endophyte treatments significantly increased root aluminum content of V. montana under T1 concentration (P < 0.05). The foliar Al content in fungi-inoculated seedlings was significantly lower than that of the non-inoculated ones under T0 and T3 levels (P < 0.05), the LRR is less than 1, while the opposite trend was observed under T2 and T4 treatments. The aluminum transport coefficient TFsoil-root and TFroot-leaf increased in different proportions under the same aluminum concentration. The findings indicate that the application of endophytic fungi change the aluminum contents and transport from rhizospheric soil, roots to leaves. The specific effects of endophytic fungi vary with the degree of aluminum stress and the fungi genus. The study proves that inoculation of endophytic fungi can improve the aluminum tolerance of host plants, and thereby play an important role in promoting the sustainable development of forestry.

Antibacterial Potential of Fungal Endophytes From Selected Seaweeds From Johor Coast

Endophytic fungi from marine seaweed have been known to be the source of new secondary biological metabolites. The ample coast in Malaysia in particular the Johor Coast has diverse marine seaweed, home to potential marine endophytic fungi. In this light, this study aims to characterise endophytic fungi in selected seaweeds from the Johor Coast and determine the antibacterial potential. Fungal endophytes were aseptically isolated from brown seaweed, Sargassum sp. and green algae, Ulva lactuca. Macroscopic and microscopic observations were performed for characterisation as fungal genera. Sequence analysis of Internal Transcribed Spacer (ITS) suggested the five fungal isolates as Trichoderma asperellum, Aspergillus aculeatus, Aspergillus fumigatus, Penicillium sp. FKI-3389 and Hypoxylon monticulosum. Antibacterial activity was determined by minimum inhibition concentration assay against five human pathogenic bacteria. Only T. asperellum, A. fumigatus and H. monticulosum showed antibacterial potential with the latter indicating broad-spectrum antibacterial activity. As a conclusion, five endophytic fungal species were successfully determined from the brown and green seaweeds. Three of the fungal endophytes showed potential in antibacterial activity with H. monticulosum displayed broad spectrum activity.

Novel endophytic fungal species Pithoascus kurdistanensis producing morphine compounds

Papaver genus, commonly known as popies, is a valuable source of alkaloids used in medicine, including papaverine, morphine, codeine, and thebaine. We isolated six endophytic fungal isolates producing morphinan alkaloids from four Papaver species growing in Kurdistan Province, Iran. To do this, a 1:1 mixture of methanol and chloroform was used to extract fungal cultures. The contents of morphinan alkaloids in the extracts were subsequently determined using phase high-performance liquid chromatography. Among the morphinan alkaloid-producing fungal isolates, IRAN 4653C had the highest yield giving 23.06 (mg/g) morphine and 2.03 (mg/g) codeine when grown in potato dextrose liquid medium. The identity of this isolate was examined and recognized as a new fungal species named as Pithoascus kurdistanesis sp. nov. based on multi-gene phylogenetic analyses of ITS, TEF-1α, and TUB2 sequences data and morphological features. The morphinan-producing endophytic fungus and the isolated Pithoascus species from Papaver are being reported for the first time. Accordingly, this fungus shows promise as a new source of valuable compounds which is illustrated and introduced here as a new Microascaceae member belonging to Pithoascus from Kurdistan Province, Iran. Moreover, the morphinan productivity of P. kurdistanesis was further validated by gas chromatography-mass spectrometry (GC–MS).

Antibacterial, Antifungal, and Cytotoxic Effects of Endophytic Streptomyces Species Isolated from the Himalayan Regions of Nepal and Their Metabolite Study.

Background/Objectives: Recently, antimicrobial-resistant pathogens and cancers have emerged as serious global health problems, highlighting the immediate need for novel therapeutics. Consequently, we aimed to isolate and characterize endophytic Streptomyces strains from the rhizospheres of the Himalayan region of Nepal and identify specialized metabolites with antibacterial, antifungal, and cytotoxic potential. Methods: To isolate Streptomyces sp., we collected two soil samples and cultured them on an ISP4 medium after pretreatment. We isolated and identified the strains PY108 and PY109 using a combination of morphological observations and 16S rRNA gene sequencing. Results: The BLAST results showed that PY108 and PY109 resembled Streptomyces hundungensis PSB170 and Streptomyces sp. Ed-065 with 99.28% and 99.36% nucleotide similarity, respectively. Antibacterial assays of ethyl acetate (EA) extracts from both isolates PY108 and PY109 in a tryptic soy broth (TSB) medium were conducted against four pathogenic bacteria. They showed significant antibacterial potential against Staphylococcus aureus and Klebsiella pneumoniae. Similarly, these extracts exhibited moderate antifungal activities against Saccharomyces cerevisiae and Aspergillus niger. Cytotoxicity assays on cervical cancer cells (HeLa) and breast cancer cells (MCF-7) revealed significant potential for both extracts. LC-MS/MS profiling of the EA extracts identified 27 specialized metabolites, including diketopiperazine derivatives, aureolic acid derivatives such as chromomycin A, and lipopeptide derivatives. In comparison, GC-MS analysis detected 34 metabolites, including actinomycin D and γ-sitosterol. Furthermore, a global natural product social molecular networking (GNPS)-based molecular networking analysis dereplicated 24 metabolites in both extracts. Conclusions: These findings underscore the potential of endophytic Streptomyces sp. PY108 and PY109 to develop new therapeutics in the future.

Identification and Antagonistic Potential of Bacillus atrophaeus against Wheat Crown Rot Caused by Fusarium pseudograminearum

Fusarium pseudograminearum (Fpg) is a significant pathogen responsible for fusarium crown rot (FCR) in wheat (Triticum aestivum L.), a disease with devastating impacts on crop yield. The utilization of biocontrol bacteria to combat fungal diseases in plants is a cost-effective, eco-friendly, and sustainable strategy. In this trial, an endophytic bacterial species, designated as SW, was isolated from the roots of wheat. The strain exhibited potent antagonistic effects against Fpg and reduced the FCR disease severity index by 76.07 ± 0.33% in a greenhouse pot trial. Here, 106 colony-forming units (CFUs)/mL of the SW strain was determined to be the minimum dose required to exhibit the antagonism against Fpg. The strain was identified as Bacillus atrophaeus using genome sequencing and comparison with type strains in the NCBI database. Whole-genome sequencing analysis revealed that SW harbors genes for siderophores, antifungal metabolites, and antibiotics, which are key contributors to its antagonistic activity. Additionally, the strain’s ability to utilize various carbon and nitrogen sources, successfully colonize wheat root tissues as an endophyte, and form biofilms are critical attributes for promoting plant growth. In summary, these findings demonstrate the ability of Bacillus atrophaeus to control FCR disease in wheat in a sustainable agricultural setting.

Endophytes infection increased the disease resistance of host Achnatherum sibiricum and non-symbiotic neighbours to pathogenic fungi

Epichloë infection can affect the fungal disease resistance of host grasses. However, few studies have been reported on the effects of endophyte infection on non-symbiotic neighbours. We surveyed the plant diseases in natural grassland, and compared differences of total disease index between neighboring and non-neighboring plants of Achnatherum sibiricum. Then laboratory experiments were conducted to investigate the effects of endophyte on the growth of four pathogen species as well as the brown patch of the host and its neighboring plants. The results of plant disease investigation in natural grassland showed that the major epidemic diseases of grasses were spot blight, rust disease and powdery mildew in Hulunbuir natural grassland. Among common herbages, the total disease index of endophyte-infected A. sibiricum was the lowest. Compared with non-neighboring plants, the brown patch disease index of Leymus chinensis, Stipa baicalensis and Agropyron cristatum was significantly reduced when neighbouring with A. sibiricum. The laboratory experiments results showed that the culture filtration of both Epichloë gansuensis and Epichloë sibiricum significantly restrained the growth of Curvularia lunata, Bipolaris sorokiniana, Sclerotinia sclerotiorum and Sclerotinia trifoliorum. The two species of endophytes could reduce lesion area of detached host leaves. In vivo plant experiments, the endophyte reduced the disease resistance of both the host and its neighbor grasses L. chinensis to C. lunata and B. sorokiniana. This study first verified that the endophytes in A. sibiricum have a positive effect on disease resistance of neighbor grasses to brown patch. The study contributes to the understanding of endophyte-host interactions and suggests potential applications of endophytes in biological control strategies for grassland management.

Endophytic fungi of spurred mangrove, Ceriops tagal and its bioactivity potential: Predominance of Aspergillus species and its ecological significance

Fungal endophytes were isolated from the leaves of spurred mangrove, Ceriops tagal and the isolation frequency was found to be 11.66 %. The endophytes were identified by both morphological and molecular methods. A total of 106 endophytic fungi were isolated with the majority (96 %) belonging to the Ascomycota and Basidiomycota constituted only 4 % of the total isolates. Within Ascomycota, three classes (Sordariomycetes, Eurotiomycetes, and Saccharomycetes) and 4 orders were observed. In Basidiomycota only agaricomycetes was obtained. Aspergillus (58 %) was the dominant genus, followed by Penicillium (20 %), Colletotrichum (9 %), and Schizophyllum (6 %). Notably, Aspergillus sydowii (35 %) was the predominant endophytic fungus in C. tagal. The colonization frequency was highest for Aspergillus sydowii (4.1 %) followed by Penicillium citrinum (3 %) and Aspergillus flavus (2.3 %). In total, 11 endophytic fungal species were identified from C. tagal. The isolates exhibited noteworthy hydrolytic enzyme production and antimicrobial properties, suggesting their suitability for potential applications as bioremediators and antimicrobials in aquaculture and medicine.

Identification, Characterization, and Antibacterial Evaluation of Five Endophytic Fungi from Psychotria poeppigiana Müll. Arg., an Amazon Plant.

Endophytic fungi, residing within plants without causing disease, are known for their ability to produce bioactive metabolites with diverse properties such as antibacterial, antioxidant, and antifungal activities, while also influencing plant defense mechanisms. In this study, five novel endophytic fungi species were isolated from the leaves of Psychotria poeppigiana Müll. Arg., a plant from the Rubiaceae family, collected in the tropical Amazon region of Bolivia. The endophytic fungi were identified as a Neopestalotiopsis sp., three Penicillium sp., and an Aspergillus sp. through 18S ribosomal RNA sequencing and NCBI-BLAST analysis. Chemical profiling revealed that their extracts obtained by ethyl acetate contained terpenes, flavonoids, and phenolic compounds. In a bioautography study, the terpenes showed high antimicrobial activity against Escherichia coli. Notably, extracts from the three Penicillium species exhibited potent antibacterial activity, with minimum inhibitory concentration (MIC) values ranging from 62.5 to 2000 µg/mL against all three pathogens: Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis (both Gram-positive and Gram-negative bacteria). These findings highlight the potential of these endophytic fungi, especially Penicillium species as valuable sources of secondary metabolites with significant antibacterial activities, suggesting promising applications in medicine, pharmaceuticals, agriculture, and environmental technologies.

Potential effect of novel endophytic nitrogen fixing diverse species of Rahnella on growth promotion of wheat (Triticum aestivum L.)

Potential effect of novel endophytic nitrogen fixing diverse species of Rahnella on growth promotion of wheat (Triticum aestivum L.)

Current Status and the Role of Biofilm Biofertilizer for Improving the Soil Health and Agronomic Efficiency of Maize on Marginal Soil

The use of biofilm biofertilizers is emerging as a promising strategy to improve soil health and agronomic efficiency, especially for maize production on marginal soils. This review focuses on the current status and critical role of biofilm biofertilizers in improving soil properties and maize productivity. This study used Preferred Reporting Items for Systematic Reviews and Meta-Analyses using Scopus and ScienceDirect databases from 2014-2024. Results showed that current status of biofilm biofertilizer utilization is spread on azolla, rhizobacteria, and endophytic bacteria species. Biofilm biofertilizers are beneficial microbial communities encapsulated in extracellular polymeric substances (EPS) that contribute to soil structure stabilization, nutrient solubilization and improved water retention. Application of these biofertilizers has been shown to improve soil fertility by increasing organic matter content, promoting nutrient cycling, and stimulating microbial activity. These improvements result in better root development, higher plant growth rates and increased crop yields. Especially on marginal soils, where nutrient availability and soil structure are often compromised, biofilm biofertilizers offer a sustainable solution to mitigate these limitations. This review synthesizes findings from recent studies and highlights the mechanisms by which biofilm biofertilizers exert their beneficial effects, thereby highlighting their potential in sustainable agricultural practices for maize production on suboptimal soils.

Endophytic actinomycetes promote growth and fruits quality of tomato (Solanum lycopersicum): an approach for sustainable tomato production.

Tomato, a fruit with a high vitamin content, is popular for consumption and economically important in Thailand. However, in the past year, the extensive usage of chemicals has significantly decreased tomato yields. Plant Growth-Promoting Rhizobacteria (PGPR) is an alternative that can help improve tomato production system growth and yield quality while using fewer chemicals. The present study aimed to determine whether endophytic actinomycetes promote growth and fruit quality of tomato (Solanum lycopersicum). The experiment was conducted in a net-houses at the Center for Agricultural Resource System Research, Faculty of Agriculture, Chiang Mai University, Chiang Mai province, Thailand. The randomized completely block design (RCBD) was carried out for four treatments with three replications, which was control, inoculation with TGsR-03-04, TGsL-02-05 and TGsR-03-04 with TGsL-02-05 in tomato plant. Isolated Actinomycetes spp. of each treatment was then inoculated into the root zone of tomato seedlings and analyzed by Scanning Electron Microscopy (SEM). The height of tomato plants was measured at 14, 28, 56, and 112 days after transplanting. Final yield and yield quality of tomato was assessed at the maturity phase. The SEM result illustrated that the roots of tomato seedlings from all treatments were colonized by endophytic actinomycetes species. This contributed to a significant increase in plant height at 14 days after transplanting (DAT), as found in the TGsR-03-04 treatment (19.40 cm) compared to the control. Besides, all inoculated treatments enhanced tomato yield and yield quality. The highest weight per fruit (47.38 g), fruit length (52.37 mm), vitamin C content (23.30 mg 100g-1), and lycopene content (145.92µg g-1) were obtained by inoculation with TGsR-03-04. Moreover, the highest yield (1.47 kg plant-1) was obtained by inoculation with TGsL-02-05. There was no statistically significant difference in the number of fruits per plant, fruit width, brix, and antioxidant activity when various inoculations of endophytic actinomycetes were applied. Therefore, the use of endophytic actinomycetes in tomato cultivation may be an alternative to increase tomato yield and yield quality.

Earthworm modifies microbial community and functional genes for lignocellulosic waste valorization: Isolating plant-growth-promoting bacteria via next generation sequencing

The primary motivation of this study is the lack of knowledge regarding the shift in microbial community and functional compositions in lignocellulosic waste-based composting and vermicomposting systems. To date, the next-generation sequencing approaches have scantily been made for the isolation of plant-growth-promoting microorganisms from vermicomposting systems. Therefore, two types of lignocellulosic waste (paddy straw and food waste) are mixed with and without cow dung in different ratios and vermicomposted with Eisenia fetida, while using a series of aerobic composting as a control. Significant decreases in pH, organic C (∼3 fold), and XRD-derived crystallinity are seen most evidently in the paddy straw-food waste (1:1) mixtures upon vermicomposting (compared to composting) along with a concurrent increment of nutrients (NPK) (∼2–3.5 fold). Significant augmentation (P < 0.01) in microbial activity (biomass and respiration) and growth (bacteria and fungus) is observed under vermicomposting. A considerable shift in taxonomic diversity, accompanied by differential functional diversity of the microbial communities, is detected between paddy straw-food waste (1:1) vermicompost and compost after 60 days of incubation. The overall gene volume is greater in the vermibed than in the compost, and genes of a few well-known microbial communities with good plant growth promoting traits (e.g., Beijerinckiaceae and Propionibacteriaceae) are exclusive to the vermicompost. Additionally, genes associated with beneficial microbial activities, such as amino acid transport, nuclear structure development, and lipid transport, are found to be more abundant in vermicompost than in compost. These data are helpful in identifying suitable feedstock for isolating scalable microbial species with beneficial traits. Subsequently, six multi-dimensional plant-growth-promoting endophytic bacterial species are isolated from both the vermibed and earthworm guts. Interestingly, close genetic resemblances are found for a few of these isolates with the metagenomically detected genes. In conclusion, this is the first study to identify the practical utility of next-generation sequencing-based metagenomic analyses for the meaningful isolation of economically viable microbial species from vermicomposting systems that might replace a sizeable portion of the chemical fertilizers used in agriculture.

Navigating the Fusarium species complex: Host-range plasticity and genome variations

The Ascomycete genus Fusarium, first introduced by Link in 1809, currently consists of 431 species and 3558 unclassified isolates and hybrids (according to NCBI Taxonomy lists). Collectively, these fungi have diverse lifestyles and infection cycles exploiting a wide range of environments, hosts, ecological niches, and nutrient sources. Here, we carried out a pan-Fusarium species review to describe and explore the glamorous, and the less attractive niches, exploited by pathogenic and endophytic species. We survey species that infect plant, human, animal and/or invertebrate hosts, free-living non-pathogenic species dwelling in land, air or water-based natural ecosystems, through to those species that exploit human-modified environments or are cultivated in industrial production systems. Fully sequenced, assembled and annotated reference genomes are already available for 189 Fusarium species, many at chromosome scale. In addition, for some of the world's most important species extensive single species pangenomes or closely related formae speciales genome clusters are readily available. Previous comparative genomics studies have focussed on taxonomically restricted clusters of Fusarium species. We now investigate potential new relationships between these vastly contrasting Fusarium biologies, niches and environmental occupancies and the evolution of their respective genomes.

Molecular Identification and Pathogenicity of Fusarium Species Associated with Wood Canker, Root and Basal Rot in Turkish Grapevine Nurseries.

Fusarium species are agriculturally important fungi with a broad host range and can be found as endophytic, pathogenic, or opportunistic parasites in many crop plants. This study aimed to identify Fusarium species in bare-rooted, dormant plants in Turkish grapevine nurseries using molecular identification methods and assess their pathogenicity. Asymptomatic dormant plants were sampled from grapevine nurseries (43) in different regions of the country, and fungi were isolated from plant roots and internal basal tissues. The Fusarium strains were identified by performing gene sequencing (TEF1-α, RPB2) and phylogenetic analyses. Pathogenicity tests were carried out by inoculating mycelial agar pieces of strains onto the stem or conidial suspensions into the rhizosphere of vines (1103 Paulsen rootstock). Laboratory tests revealed that Fusarium species were highly prevalent in Turkish grapevine nurseries (41 out of 43). Gene sequencing and phylogenetic analyses unraveled that 12 Fusarium species (F. annulatum, F. brachygibbosum, F. clavum, F. curvatum, F. falciforme, F. fredkrugeri, F. glycines, F. nanum, F. nematophilum, F. nirenbergiae, F. solani, and Fusarium spp.) existed in the ready-to-sale plants. Some of these species (F. annulatum, F. curvatum and F. nirenbergiae) consistently caused wood necrosis of seedling stems, rotting of the basal zone and roots, and reduced root biomass. Although the other nine species also caused some root rot and root reduction, their virulence was not as severe as the pathogenic ones, and they were considered opportunistic parasites or endophytic species. This study suggests that Fusarium species might play an important role in root-basal rot, wood canker symptoms, and young vine decline in Turkish grapevine nurseries and that these species need to be considered for healthy seedling production.

In vitro antifungal effect of endophytic fungi of creole cucurbits of Yucatan

Endophytic fungi are plant symbiont microorganisms, diverse and abundant in tropical regions, with great potential as biocontrol agents of agricultural fungal diseases. The objective of the present work was to evaluate in vitro antifunfal activity of endophytic fungi associated with creole cultivars of Cucumis sativus and Lagenaria siceraria from Yucatán. The endophytic strains were isolated and identified from different organs, to be subjected to dual confrontations and antibiotic tests. Twenty species with antifungal effects against Corynespora cassiicola, Colletotrichum truncatum and Fusarium equiseti were identified, obtaining inhibition ranges of 17.72–100%, 16.51–91.55% and 4.64–91.89%, respectively. Aspergillus flavus, Lasiodiplodia pseudotheobromae and Trichoderma longibrachiatum exhibited the highest percentages of inhibition against the three phytopathogens. Likewise, these three species of endophytes demonstrated an antibiotic effect in their extracts, mainly inhibiting the growth of F. equiseti by up to 46.46%. The L. pseudotheobromae strain has characteristics that give it potential as an antifungal agent, so its applications and growth conditions should continue to be explored. This work represents a first effort to understand the diversity of endophytic fungi in native crops in the region.