Endophytic Genera Research Articles

Fungal Trunk Diseases Causing Decline of Apricot and Plum Trees in the Czech Republic.

Fungal trunk diseases (FTDs) have been a significant threat to the global stone fruit industry. FTDs are caused by a consortium of wood-decaying fungi. These fungi colonize woody tissues, causing cankers, dieback, and other decline-related symptoms in host plants. In this study, a detailed screening of the fungal microbiota associated with the decline of stone fruit trees in the Czech Republic was performed. The wood fragments of plum and apricot trees showing symptoms of FTDs were subjected to fungal isolation. The partial internal transcribed spacer region, partial beta-tubulin, and translation elongation factor 1-α genes were amplified from genomic DNA extracted from fungal cultures. All isolates were classified, and the taxonomic placement of pathogenic strains was illustrated in phylogenetic trees. The most abundant pathogenic genus was Dactylonectria (31%), followed by Biscogniauxia (13%), Thelonectria (10%), Eutypa (9%), Dothiorella (7%), Diplodia (6%), and Diaporthe (6%). The most frequent endophytic genus was Aposphaeria (17%). The pathogenicity of six fungal species (Cadophora daguensis, Collophorina africana, Cytospora sorbicola, Dothiorella sarmentorum, Eutypa lata, and E. petrakii var. petrakii) to four Prunus spp. was evaluated, and Koch's postulates were fulfilled. All tested isolates caused lesions on at least one Prunus sp. The most aggressive species was E. lata, which caused the largest lesions on all four tested Prunus spp., followed by E. petrakii var. petrakii and D. sarmentorum. Japanese plum (Prunus salicina) and almond (P. amygdalus) were the most susceptible hosts, while apricot (P. armeniaca) was the least susceptible host in the pathogenicity trial.

Endophytic genera in californian thistle (Cirsium arvense (L.) Scop.)

Cirsium arvense is an important weed in temperate areas, causing yield losses in pasture and cropping systems. Endophytes may affect fungal biocontrol agents deployed to control C. arvense. This was the first study sampling leaves, stems, and roots of C. arvense multiple times in one growing season to determine which endophytic genera were associated with this plant species. Eighty-eight endophytic genera were isolated by culture methods and identified with molecular markers. Sixty-five of these have not previously been reported for C. arvense. This study was the first to document many genera belonging to the orders Pleosporales, Hypocreales, and Diaporthales that have not previously been identified in association with C. arvense. In addition, this study isolated more Leotiomycetes and Helothiales than previous studies on C. arvense endophytes. Information on endophytic genera in C. arvense will aid our understanding of biotic factors influencing fungal biocontrol agents and may improve effectiveness of biocontrol agents.

Identification and characterization of Cladosporium species associated with tea plants (Camellia sinensis) in China

AbstractThe tea plant (Camellia sinensis) is widely cultivated worldwide as one of the most popular non‐alcoholic beverage crops. Cladosporium, the dominant endophytic genus of leaves, possesses a variety of biotransformation and metabolic abilities to promote the accumulation of secondary metabolites. However, Cladosporium species in tea leaves remain unexplored. In this study, a total of 79 Cladosporium isolates were obtained from the leaves of several tea varieties in China. Multilocus phylogenetic analysis and morphological characteristics revealed six known species, namely, C. angulosum, C. anthropophilum, C. halotolerans, C. perangustum, C. tenuissimum and C. xanthochromaticum, and one novel species named C. camelliae. C. angulosum was the most dominant species, and the other six species were newly recorded in tea plants. Pathogenicity tests showed no obvious symptoms of disease in tea leaves caused by 13 representative strains of these seven Cladosporium species. Subsequently, three frequently used fungicides were tested, including chlorothalonil, pyraclostrobin and thiophanate‐methyl. The EC50 values against C. tenuissimum were 19.14, 0.548 and 3.796 μg/mL, respectively. Based on these EC50 values, the inhibition effects of the three fungicides on six strains from six species (C. angulosum, C. anthropophilum, C. camelliae, C. perangustum, C. tenuissimum and C. xanthochromaticum) were further compared. Pyraclostrobin had the strongest inhibitory effects on the mycelial growth of Cladosporium, followed by thiophanate‐methyl, and chlorothalonil showed the weakest inhibitory effect. The results provide a basis for understanding endophytic Cladosporium fungi in tea leaves.

Characterization of heterogeneous groups of fungal endophytes isolated from mangroves in Negombo, Sri Lanka

Mangroves are well known for their adaptability to extreme conditions; thus, mangrove habitats help to manage coastlines and carbon cycling against anthropogenic stresses. Fungal endophyte is a type of microorganism that typically has a mutualistic relationship with its plant hosts. These endophytes can be found in several parts of the plant and play a positive role in the production of enzymes, nutrients and secondary metabolites, along with other processes such as toxin assembly and phyto-stimulation. The exploitation of these bioactive substances from endophytic fungi is beneficial in several fields such as pharmaceuticals and agriculture. The objective of the current investigation was to isolate and identify fungal endophytes present in ten mangrove species from Negombo, Sri Lanka: Acanthus ilicifolius, Acrostichum aureum, Avicennia marina, Bruguiera cylindrica, Bruguiera gymnorrhiza, Excoecaria agallocha, Lumnitzera racemosa, Rhizophora mucronata, Sonneratia alba and Sonneratia caseolaris. A standard potato dextrose agar culturing was used to obtain fungal colonies from leaves, roots and twigs, whose morphological characteristics were used for their identification. Out of the 42 fungal isolates extracted from the samples, nine endophytic genera such as Aspergillus, Candida, Chaetomium, Fusarium, Mucor, Penicillium, Phyllosticta, Rhizopus and Trichoderma were found. The highest number of isolates was obtained from Sonneratia alba. Each mangrove species held varying types of fungal colonies, with the genus Penicillium being isolated the highest number of times and the genus Aspergillus being highly diverse. The findings of this study have helped to confirm the presence of endophytic fungi in all the sample mangroves tested.

Antimicrobial activities and phytochemical screening of endophytic fungi isolated from Cymbidium and Dendrobium orchids

• Cymbidium and Dendrobium orchids harbor diverse endophytic fungi. • These endophytic fungi have antimicrobial activities. • Fusarium was the dominant genus of endophytes from orchids. • Novel discovery of Buergenerula spartinae and Exserohilum rostratum from orchids. This study reports the isolation of fungal endophytes from common orchids in Malaysia ( Cymbidium and Dendrobium sp.), their antimicrobial activities and phytochemical constituents. Culturable fungal endophytes were sampled from surface-sterilized root tissues of Cymbidium and Dendrobium orchids, then identified via molecular approaches. To establish their antibacterial and antifungal activities, the identified fungal endophytes were tested by the agar well diffusion assay and dual culture technique, respectively. Results revealed a total of 59 fungal endophytes were isolated, and they were represented in eight different genera ( Fusarium, Nigrospora, Lasiodiplodia, Exserohilum, Curvularia, Buergenerula, Trichoderma and Daldinia ). Fusarium was the most dominant genus among the pool of isolates, with high isolation frequencies of 62.7% (37 isolates). Rare genera such as Buergenerula and Exserohilum were also discovered at lower frequencies (3.33%, 1 isolate each). Among the 59 isolates, 8 isolates (13.56%) demonstrated antibacterial activities (5.67 ± 0.58 to 25 ± 0.00 mm) against all 4 pathogens tested ( Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa ) . All endophytic isolates were, however, capable of inhibiting the growth of at least one pathogenic fungus ( Ganoderma boninense, Pythium ultimum, Fusarium solani, Candida albicans ) (1.16 to 91.86% inhibition). Prominent antimicrobial activities were displayed by Fusarium incarnatum (C4) and Trichoderma asperellum (D7). Phytochemical analysis of extracts from these endophytes revealed that antimicrobial activities may be attributed to constituents like alkaloids, flavonoids, phenols, saponins, tannins and terpenoids. These results highlighted the potential of fungal endophytes from Orchidaceae as an alternative source for antimicrobial agents.

Deep sequencing across multiple host species tests pine-endophyte specificity.

Foliar fungal endophytes vary in their distributions across landscapes or plant host taxa, indicative of specialized ecologies and host specific adaptations. Accounts of specialization, however, depend on the taxonomic breadth and geographic range of the host plants included in each study. A broad region-scale study or deep sampling of diverse potential host species still remains relatively rare but is becoming increasingly possible with high-throughput sequencing. Amplicon sequencing was used to rapidly identify the fungal endophytic community among six pine (Pinus, Pinaceae) species co-occurring across northeastern United States and to test for site and host specialization. We focused on the endophytic genus Lophodermium (Rhytismataceae), whose species members are thought to specialize on different pine species, to test if amplicon sequencing could rapidly verify previously implied or discover new patterns of host specificity. While amplicon sequencing could analyze more samples at greater depths and recover greater numbers of unique Lophodermium taxa than when endophyte communities were surveyed with traditional culturing methods, patterns of specialization were not better supported. This may be because amplicon sequencing can indiscriminately capture non-host specific organisms found incidentally from plant tissues or because we have overestimated host-specificity in the past with biased culturing techniques. Amplicon sequencing can quickly identify patterns of host specificity by allowing large-scale surveys but has limitations in quantifying the level of intimacy of these relationships.

Dramatic effect of black soldier fly larvae on fungal community in a compost.

Black soldier fly larvae (BSFL) offer very good prospects for the production of cheap and high-quality dietary protein. This insect is able to consume low-quality substrates, including food waste. The properties and safety of the compost obtained are largely determined by its microbiome. However, while the bacterial component of the BSFL-compost microbiome has been much studied, little is known about its fungal component. In plant-based rearing substrates both the biomass and the metabolic activity of fungi often exceed the biomass and the activity of prokaryotes. So, the purpose of this study was to investigate the fungal community of the compost produced by BSF larvae reared on a food waste substrate. Community structure was determined by metabarcoding of the ITS (internal transcribed spacer) region. Species composition and abundance were determined using the plating technique and subsequent identification of the isolated pure cultures. It was found that the primary mycobiome of the food waste substrate that was used consisted of 19 families, represented mainly by phytopathogenic and endophytic genera. Larva incubation led to the complete elimination of all mycelial fungi from the resulting compost. The final mycobiome consisted of only two yeast species, Pichia kudriavzevii and Diutina rugosa, with a total abundance of 1.2 × 107 CFU g-1 . The rearing of BSFL led to the complete elimination of mycelial fungi from its feed substrate. The final compost lacked harmful fungi, including molds. This information may be crucial for BSF compost utilization. The phenomenon was also an interesting aspect of zoomicrobial interactions in nature and agriculture. © 2021 Society of Chemical Industry.

Antagonism to Plant Pathogens by Epichloë Fungal Endophytes-A Review.

Epichloë is a genus of filamentous fungal endophytes that has co-evolved with cool-season grasses with which they form long-term, symbiotic associations. The most agriculturally important associations for pasture persistence for grazing livestock are those between asexual vertically transmitted Epichloë strains and the pasture species, perennial ryegrass, and tall fescue. The fungus confers additional traits to their host grasses including invertebrate pest deterrence and drought tolerance. Selected strains of these mutualistic endophytes have been developed into highly efficacious biocontrol products and are widely utilized within the Americas, Australia, and New Zealand for pasture persistence. Less publicized is the antagonism Epichloë endophytes display towards multiple species of saprophytic and pathogenic microbes. This opinion piece will review the current literature on antimicrobial properties exhibited by this genus of endophyte and discuss the reasons why this trait has historically remained a research curiosity rather than a trait of commercial significance.

First record of Mikrosyphar zosterae (Chordariaceae, Phaeophyceae) in the southern hemisphere and as an endophyte in the brown algal genera Leathesia and Colpomenia

Several filamentous endophytic genera are assigned to the Phaeophyceae, in particular to the family Chordariaceae (Cormaci et al. 2012). Brown endophytic filamentous algae are known to cause infections in host marine algae (Schoenrock et al. 2013; Ogandaga et al. 2016, 2017; Gao et al. 2019). Acting as pathogens, they may cause morphological, physiological and ecological changes in the host alga such as production of galls and wart-like spots, changes in metabolism and growth rates, and changes in survivorship and reproduction (Schoenrock et al. 2013; Ogandaga et al. 2016, 2017; Gao et al. 2019). Among brown algal filamentous endophytes, the genus Mikrosyphar Kuckuck is relatively understudied. To date, only Mikrosyphar zosterae Kuckuck (1895: 177) was studied thoroughly (Ogandaga et al. 2016, 2017).

Endophytic fungal assemblages of Zanthoxylum oxyphyllum Edgew. and their antimicrobial potential

Zanthoxylum oxyphyllum Edgew. is a medicinal plant widely been used by the local tribal communities of Assam as an alternative source of medicine for the treatment of various diseases. In the present study, endophytic fungi associated with Z. oxyphyllum were undertaken with an aim to investigate the isolates for their antimicrobial potential. The endophytic fungi were recovered using four different media, namely, Malt Extract Agar (MEA) media, Potato Dextrose Agar (PDA) media, Water Agar (WA) media and media amended with the Plant Extract (PEA) from samples collected from three sites. Altogether, 18 isolates of endophytic fungi were isolated from 150 surface sterilized and healthy leaf fragments. Colletotrichum was found to be dominant endophytic genus with 7 different species. Other isolated endophytic fungal genera were Fusarium, Curvularia, Aspergillus, Corynespora and isolates belonging non-sporulating fungi categorised as Mycelia Sterilia. The endophytic fungi were determined for antimicrobial activity against selected clinically significant human pathogenic test organisms. Ethyl acetate crude extracts of all endophytic fungi exhibited antimicrobial activity by inhibiting a minimum of one of the four test pathogens. Amongst the isolates, crude extracts obtained from Fusarium sp. and five Colletotrichum spp. showed wide-spectrum antimicrobial activity against all the test organisms. The study indicated that Z. oxyphyllum harbours a wide range of endophytes capable of producing secondary metabolites with antimicrobial properties. Further detailed investigation of their bioactive metabolites might lead to discovery of compounds with potential therapeutic applications as a new source of medicine.

Bioprospection and molecular phylogeny of culturable endophytic fungi associated with yellow passion fruit

Endophytic microorganisms live inside the plants without causing any damage to their hosts. In the agricultural field, these endophytes might be a strategy of biological control for phytopathogens. We aimed to isolate endophytic fungi from yellow passion fruit (Passiflora edulis) leaves, evaluating its biocontrol capacity by in vitro antagonism against phytopathogen Colletotrichum sp. CNPU378. We also carried out greenhouse experiments in bean seedlings. A high colonization frequency was obtained (89%), and the molecular identification based on DNA sequencing attested Colletotrichum as the most frequent genus and minor occurrence of Curvularia endophytes. The endophytes tested showed different types of competitive interactions in in vitro antagonism inhibition rate ranging from 28.8 to 48.8%. There were 10 promising antagonists tested for their antagonist activity of crude extracts of secondary metabolites, in which strain PE-36 (20.8%) stood out among the other strains evaluated. In the greenhouse assay, plants inoculated only with endophyte Colletotrichum sp. PE-36 was symptomless and suggest that the endophyte strengthened the growth promotion in common bean plants, especially in the root length and number of leaves when compared to control plants and other treatments. Despite many fungi of Colletotrichum genus being described as causative agents of anthracnose, in this study, the plant sampled was colonized predominantly by Colletotrichum endophytes living in asymptomatic relationship. By the way, we come across a Colletotrichum sp. endophyte able to antagonize a Colletotrichum sp. pathogen.

Elucidation of the life cycle of the endophytic genus Muscodor and its transfer to Induratia in Induratiaceae fam. nov., based on a polyphasic taxonomic approach

Molecular phylogenetic studies of cultures derived from some specimens of plant-inhabiting Sordariomycetes using ITS, LSU, rpb2 and tub2 DNA sequence data revealed close affinities to strains of Muscodor. The taxonomy of this biotechnologically important genus, which exclusively consists of endophytes with sterile mycelia that produce antibiotic volatile secondary metabolites, was based on a rather tentative taxonomic concept. Even though it was accommodated in Xylariaceae, its phylogenetic position had so far remained obscure. Our phylogeny shows that Muscodor species have affinities to the xylarialean genera Emarcea and Induratia, which is corroborated by the fact that their sexual states produce characteristic apiospores. These data allow for the integration of Muscodor in Induratia, i.e. the genus that was historically described first. The multi-locus phylogenetic tree clearly revealed that a clade comprising Emarcea and Induratia forms a monophylum separate from representatives of Xylariaceae, for which we propose the new family Induratiaceae. Divergence time estimations revealed that Induratiaceae has been diverged from the Xylariaceae + Clypeosphaeriaceae clade at 93 (69–119) million years ago (Mya) with the crown age of 61 (39–85) Mya during the Cretaceous period. The ascospore-derived cultures were studied for the production of volatile metabolites, using both, dual cultures for assessment of antimicrobial effects and extensive analyses using gas chromatography coupled with mass spectrometry (GC–MS). The antimicrobial effects observed were significant, but not as strong as in the case of the previous reports on Muscodor species. The GC–MS results give rise to some doubt on the validity of the previous identification of certain volatiles. Many peaks in the GC–MS chromatograms could not be safely identified by database searches and may represent new natural products. The isolation of these compounds by preparative chromatography and their subsequent characterisation by nuclear magnetic resonance (NMR) spectroscopy or total synthesis will allow for a more concise identification of these volatiles, and they should also be checked for their individual contribution to the observed antibiotic effects. This will be an important prerequisite for the development of biocontrol strains.

Hydrogen Peroxide Metabolism in Interkingdom Interaction Between Bacteria and Wheat Seeds and Seedlings.

In endophytes, the abundance of genes coding for enzymes processing reactive oxygen species (ROS), including hydrogen peroxide (H2O2), argues for a crucial role of ROS metabolism in plant-microbe interaction for plant colonization. Here, we studied H2O2 metabolism of bread wheat (Triticum aestivum L.) seeds and their microbiota during germination and early seedling growth, the most vulnerable stages in the plant life cycle. Treatment with hot steam diminished the seed microbiota, and these seeds produced less extracellular H2O2 than untreated seeds. Using a culture-dependent approach, Pantoea and Pseudomonas genera were the most abundant epiphytes of dry untreated seeds. Incubating intact seedlings from hot steam-treated seeds with Pantoea strains triggered H2O2 production, whereas Pseudomonas strains dampened H2O2 levels, attributable to higher catalase activities. The genus Pantoea was much less represented among seedling endophytes than genus Pseudomonas, with other endophytic genera, including Bacillus and Paenibacillus, also possessing high catalase activities. Overall, our results show that certain bacteria of the seed microbiota are able to modulate the extracellular redox environment during germination and early seedling growth, and high catalase activity is proposed as a key trait of seed endophytes.

TrichoGate: An Improved Vector System for a Large Scale of Functional Analysis of Trichoderma Genes.

Species of the genus Trichoderma are ubiquitous in the environment and are widely used in agriculture, as biopesticides, and in the industry for the production of plant cell wall-degrading enzymes. Trichoderma represents an important genus of endophytes, and several Trichoderma species have become excellent models for the study of fungal biology and plant–microbe interactions; moreover, are exceptional biotechnological factories for the production of bioactive molecules useful in agriculture and medicine. Next-generation sequencing technology coupled with systematic construction of recombinant DNA molecules provides powerful tools that contribute to the functional analysis of Trichoderma genetics, thus allowing for a better understanding of the underlying factors determining its biology. Here, we present the creation of diverse vectors containing (i) promoter-specific vectors for Trichoderma, (ii) gene deletions (using hygromycin phosphotransferase as selection marker), (iii) protein localization (mCherry and eGFP, which were codon-optimized for Trichoderma), (iv) gene complementation (neomycin phosphotransferase) and (v) overexpression of encoding gene proteins fused to fluorescent markers, by using the Golden Gate cloning technology. Furthermore, we present the design and implementation of a binary vector for Agrobacterium-mediated transformation in Trichoderma to increase the homologous recombination rate and the generation of a novel selection marker based on carboxin resistance.

Culture-independent analysis of an endophytic core microbiome in two species of wheat: Triticum aestivum L. (cv. ‘Hondia’) and the first report of microbiota in Triticum spelta L. (cv. ‘Rokosz’)

The main goal of the study was to determine the structure of endophytic bacteria inhabiting different parts (endosperm, germ, roots, coleoptiles, and leaves) of two wheat species, Triticum aestivum L. (cv. ‘Hondia’) and Triticum spelta L. (cv. ‘Rokosz’), in order to provide new knowledge about the stability and/or changeability of the core microbiome in different plant organs. The endophytic core microbiome is associated with plants throughout their whole life cycle; however, plant organs can determine the actual endophytic community. Therefore, next generation sequencing with MiSeq Illumina technology was applied to identify the endophytic microbiome of T. aestivum and T. spelta. Bioinformatic analyses were performed with the use of the DADA2(1.8) package and R software (3.5.1).It was demonstrated that wheat, which is an important crop plant, was associated with beneficial endophytic bacteria inside the endosperms, germs, roots, leaves, and coleoptiles. Importantly, for the first time, biodiversity was recognized in the coleoptiles of the investigated wheat species. Flavobacterium, Pseudomonas and Janthinobacterium were shown to be common genera for both tested wheat cultivars. Among them, Pseudomonas was found to be the only endophytic genus accompanying both wheat species from the endosperm stage to the development of the leaf. Paenibacillus was recognized as a core genus for the ‘Hondia’ cv., whereas Pedobacter and Duganella constituted the core microbiome in the ‘Rokosz’ cv. In addition, the first insight into the unique and yet unrecognized endophytic microbiome of T. spelta is presented.

Fungal Endophytes Control Fusarium graminearum and Reduce Trichothecenes and Zearalenone in Maize.

Fusarium graminearum can cause Giberella Ear Rot (GER) and seedling blight in maize, resulting in major yield losses. Besides GER, the infected grains are consequently contaminated with multiple mycotoxins of F. graminearum. Zearalenone and trichothecenes, such as deoxynivalenol and its acetylated forms, are among the major mycotoxins associated with F. graminearum infection in maize. In the current work, we explored the effect of the endophytic fungal genera of Epicoccum and Sordaria, to control F. graminearum infection in comparative trials with Piriformospora spp., an elusive endophytic genus. Furthermore, we investigated the effect of these endophytes on zearalenone, deoxynivalenol, and 15-acetyldeoxynivalenol levels using in vitro and in planta assays. As plants are endowed with several detoxification mechanisms comprising e.g., glucosylation of trichothecenes, the effect of the isolated fungal endophytes on the deoxynivalenol-3-glucoside level was also assessed. In general, results showed a considerable variability in the antifungal activity, both among species and among isolates within one species. Additionally, the effect on mycotoxin levels was variable, and not necessarily related to the antifungal activity except for zearalenone levels which were consistently reduced by the endophytes. These results highlight the great potential of certain endophytic fungal strains as new biocontrol agents in agricultural science.

Double-digest RADseq loci using standard Illumina indexes improve deep and shallow phylogenetic resolution of Lophodermium, a widespread fungal endophyte of pine needles.

The phylogenetic and population genetic structure of symbiotic microorganisms may correlate with important ecological traits that can be difficult to directly measure, such as host preferences or dispersal rates. This study develops and tests a low‐cost double‐digest restriction site‐associated DNA sequencing (ddRADseq) protocol to reveal among‐ and within‐species genetic structure for Lophodermium, a genus of fungal endophytes whose evolutionary analyses have been limited by the scarcity of informative markers. The protocol avoids expensive barcoded adapters and incorporates universal indexes for multiplexing. We tested for reproducibility and functionality by comparing shared loci from sample replicates and assessed the effects of numbers of ambiguous sites and clustering thresholds on coverage depths, number of shared loci among samples, and phylogenetic reconstruction. Errors between technical replicates were minimal. Relaxing the quality‐filtering criteria increased the mean coverage depth per locus and the number of loci recovered within a sample, but had little effect on the number of shared loci across samples. Increasing clustering threshold decreased the mean coverage depth per cluster and increased the number of loci recovered within a sample but also decreased the number of shared loci across samples, especially among distantly related species. The combination of low similarity clustering (70%) and relaxed quality‐filtering (allowing up to 30 ambiguous sites per read) performed the best in phylogenetic analyses at both recent and deep genetic divergences. Hence, this method generated sufficient number of shared homologous loci to investigate the evolutionary relationships among divergent fungal lineages with small haploid genomes. The greater genetic resolution also revealed new structure within species that correlated with ecological traits, providing valuable insights into their cryptic life histories.

Genotype-specific responses to the effects of commercial Trichoderma formulations in lentil (Lens culinaris ssp. culinaris) in the presence and absence of the oomycete pathogen Aphanomyces euteiches

ABSTRACTMembers of the endophytic fungal genus Trichoderma have been established as plant-beneficial microbes and are most successful commercial biologicals in the form of bio-fertilisers, biocontrol agents, and growth stimulators. We report the variable interactions among different lentil genotypes and Trichoderma strains in both the presence and absence of biotic stress (root-rot pathogen Aphanomyces euteiches). Two commercial Trichoderma formulations, namely RootShield® (RS) and RootShield® Plus (RSP) based on T. harzianum T22 and T. virens G41, respectively, were evaluated for control of Aphanomyces root rot and plant growth promotion in 23 wild and cultivated lentil genotypes. No significant disease control was recorded with either formulation in any lentil genotype. Significant genotype-specific plant growth promotion was observed in terms of root and shoot development and leaf parameters in a genotype-specific manner. Genotypes of Lens culinaris and Lens tomentosus, both in the primary lentil gene pool, demonstrated the maximum response. The overall effect of Trichoderma treatment was markedly higher under biotically stressed conditions in comparison to unstressed conditions. In many cases, negative responses were recorded, particularly in the absence of root-rot disease. L. tomentosus PI 572390 exhibited positive responses for most of the tested parameters. Our findings clearly indicate that, in the case of lentil, plant genotype plays a major role in interactions among the tested Trichoderma strains and the plant. Moreover, the influence of Trichoderma was greater and more favourable under conditions of biotic stress vs. the absence of stress.

Community composition and diversity of endophytic fungi from the fruits of Pteroceltis tatarinowii.

Endophytic fungi from the fruit of Pteroceltis tatarinowii were studied, to understand the characteristics of microbial community composition on this ancient and peculiar wild plant. Healthy fruits were collected from areas of the natural distribution of P. tatarinowii in Langyashan Natural Reserve, Anhui Province, China. Endophytic fungi were isolated from fruit tissue, and fungal strains were classified on the basis of morphology. From 500 tissue blocks taken from fruit, a total of 428 isolates of endophytic fungi were identified and classified into 20 genera, 4 families, and 3 orders. Eighty strains showed no reproductive structures, and were classified as Mycelia sterilia (18.7%). The dominant families were Dematiaceae and Sphaeropsidaceae, occupying 38.1% and 32.9% of isolates, respectively. Alternaria and Phomopsis were the dominant genera, accounting for 27.1% and 16.8% of isolates. Different parts of the fruit had different compositions of endophytes. The highest number of fungi was isolated from seeds (19 genera, 181 strains, 42.3%), and the lowest from fruiting wings (7 genera, 88 strains, 20.6%). Alternaria was the commonest genus of endophytes, isolated from three different parts of the fruit. Phomopsis and Macrophoma were the dominant genera on carpopodium and fruiting wings, respectively. The communities on carpopodium and fruiting wings were most similar to one another (CS=0.78), while those on fruiting wings and seeds were least similar (CS=0.50). Fisher's exact test showed no significant difference between the compositions of endophytes from the carpopodium and fruiting wings, while significant diffe-rences were observed between communities on seed and carpopodium, and seed and fruiting wings.

Additions to Karst Fungi 1: Botryosphaeria minutispermatia sp. nov., from Guizhou Province, China

Botryosphaeria is a species rich genus of plant saprobes, pathogens and endophytes, with a global distribution, on a wide variety of mainly woody hosts. Recent studies have discovered a wide-ranging diversity of species in Botryosphaeria. This work adds to this increasing body of knowledge on the genus, by introducing a new species of Botryosphaeria occurring on dead wood in a terrestrial habitat in Guizhou Province, of the south China Karst region. Analysis of a combined ITS and EF1-α sequence data matrix was applied to infer the phylogenetic position of the new species in Botryosphaeria and B. minutispermatia is described and illustrated based on morphology and phylogeny. The new species is characterized by erumpent, botryose, clustered, ostiolate ascomata, bitunicate, clavate asci, filiform, rarely branched pseudoparaphyses, fusiform, hyaline ascospores and a fusicoccum-like asexual morph produced in culture and formed a distinct clade within the genus Botryosphaeria.