An ecological view of the formation of VA mycorrhizas

In spite of the major advances in understanding the functioning of symbioses between plants and arbuscular mycorrhizal fungi, details of the ecology of mycorrhizal fungi are not well documented. The benefits of the association are related to the timing and extent of colonization of roots, and fungi differ in their contribution to plant growth and presumably to soil aggregation. Knowledge of the processes that lead to successful colonization of roots by beneficial fungi at appropriate times for the host plants will form the basis of guidelines for soil management to maximize the benefits from the symbiosis. Fungi differ in the manner and extent to which they colonize roots. They also differ in their capacity to form propagules. The importance of hyphae, spores and propagules within living or dead mycorrhizal roots also differs among species and for the same species in different habitats. The relationships between colonization of roots and propagule formation, and between propagule distribution and abundance and subsequent mycorrhiza formation, for different fungi in field environments, are not well understood. Methods for quantifying mycorrhizal fungi are not especially suitable for distinguishing among different fungi within roots. Consequenctly, the dynamics of colonization of roots by different fungi, within and between seasons, have been little studied. Research is required that focuses on the dynamics of fungi within roots as well as on changes in the abundance of propagules of different fungi within soil. Interactions between fungi during the colonization of roots, the colonization of soil by hyphae and sporulation are all poorly understood. Without knowledge of these processes, it will by difficult to predict the likely success of inoculation with introduced fungi. Such knowledge is also required for selecting soil management procedures to enhance growth and survival of key species within the population. The relative tolerance of various fungi to perturbations in their surroundings will provide a basis for identifying those fungi that are likely to persist in specific environments. The processes that influence mycorrhizal fungi in field soils can be identified in controlled studies. However, greater emphasis is required on studying these processes with mixed populations of fungi. The role played by diversity within populations of mycorrhizal fungi is virtually unexplored.     

SOME ASPECTS OF THE PHYSIOLOGY AND BIOCHEMISTRY OF MARINE FUNGI

1. This review deals with certain aspects of the physiology and biochemistry of marine fungi. Though it is not easy to define what is meant by a marine fungus, the information presented here relates to those species that by consensus can be accepted as being truly marine. The material is in two parts, that relating to the higher fungi (Ascomycotina, Basidiomycotina and Deuteromycotina) and that relating to the lower fungi, particularly those zoosporic fungi that require sodium for growth. 2. Higher marine fungi appear to have a similar carbon, nitrogen and vitamin nutrition to their terrestrial counterparts. 3. Growth of higher marine fungi can be optimal in 100% sea water, but more frequently optimal growth is at a lower percentage. The percentage giving optimal growth may be determined by the rate of ion uptake required to generate the necessary turgor for growth. The tolerance of the vegetative phase of many terrestrial fungi to salinity appears little different from that of marine fungi. In general, members of the Basidiomycotina are particularly sensitive to salinity, while those of the Ascomycotina and Deuteromycotina are much more tolerant. 4. The degree of tolerance to salinity may be dependent upon temperature and whether or not adaptation by the fungus has occurred. 5. Maintenance of a suitable internal potassium concentration by a higher marine fungus is important for growth in a saline medium. Calcium appears to be necessary for the retention of potassium and organic solutes within the hyphae. 6. It appears that higher marine fungi are able to maintain a ratio of potassium: sodium higher than that of sea water by the presence of a plasma membrane ATPase which may have a higher pH optimum than the equivalent enzyme from terrestrial counterparts. 7. Higher fungi produce more glycerol as the salinity of the external medium is increased. Whether or not the compound is involved in osmoregulation has yet to be determined. 8. Turgor is thought to be generated in higher marine fungi growing in sea water by organic solutes (predominantly glycerol and arabitol) and by ions, with the latter playing the major role. Though interpretation of the data depends on several assumptions, the high concentrations of sodium that seem likely to be present in hyphae or cells have implications for the activity of enzymes, if they have similar properties to those of higher plants. There is a need for information on the effects of high concentrations of ions on enzymes located in the cytoplasm of higher fungi. 9. In spite of some experimental uncertainties, it seems that reproduction and spore germination of higher marine fungi are very much less affected by salinity than are the same processes of terrestrial counterparts. 10. The zoosporic marine fungi require sodium for growth. Though the ion is required at high concentration for growth, sodium cannot be replaced by potassium. Evidence indicates that sodium is involved in the transport of solutes across the plasma membrane. 11. The carbon and nitrogen requirements for the growth of the zoosporic marine fungi demand further investigation, particularly at the biochemical level. There is evidence that the respiration of these fungi possesses many interesting features. 12. Vitamin requirements of the zoosporic marine fungi depend on the isolate under investigation. Vitamin B., does not now seem to be an obligatory requirement. The ability of phospholipids and sterols to stimulate growth requires further investigation. 13. Further studies on marine fungi in the laboratory should focus particularly on growth in continuous culture. Physiological and biochemical studies would be helped by more precise guidance from those concerned with the ecology of these fungi.     

Using Species Distribution Models For Fungi

Species distribution models (SDMs) are an emerging tool in the study of fungi, and their use is expanding across species and research topics. To summarise progress to date and to highlight important considerations for future users, we review 283 studies that apply SDMs to fungi. We found that macrofungi, lichens, and pathogenic microfungi are most often studied. While many studies only aim to model species response to environmental covariates, the use of SDMs for explicitly predicting fungal occurrence in space and time is growing. Many studies collect fungal occurrence data, but the use of pre-collected records from reference collections and citizen science programs is increasing. Challenges of applying SDMs to fungi include detection and sampling biases, and uncertainties in identification and taxonomy. Further, finding environmental covariates at appropriate spatial and temporal scales is important, as fungi can respond to fine-scale environmental patterns. Fine-scale covariate data can be difficult to gather across space, but we show remote-sensing measurements are viable for fungi SDMs. For those fungi interacting with host species, host information is also important, and can be used as covariates in SDMs. We also highlight that competition among fungi, and dispersal, can affect observed distributions, with the latter particularly prominent for invasive fungi. We show how one can account for these processes in models, when suitable data are available. Finally, we note that environmental DNA records create new opportunities and challenges for future modelling efforts, and discuss the difficulties in predicting invasions and climate change impacts. The application of SDMs to fungi has already provided interesting lessons on how to adapt modelling tools for specific questions, and fungi will continue to be relevant test subjects for further technical development of SDMs.     

Interactions between wood-inhabiting fungi and termites: a meta-analytical review

The foraging behavior and survivorship of termites are modified by the presence of wood-inhabiting fungi. Nonetheless, it is not clear if these interactions are beneficial, negative, or neutral for termites. We conducted a meta-analytical review to determine if the presence of wood-inhabiting fungi affects the foraging behavior and survivorship of termites. Overall, the presence of wood-inhabiting fungi in a resource used by termites was positive, increasing resource consumption by 120%, and aggregation behavior by 81%. The presence of fungi also increased termite trail-following by approximately 200% and increased survival by 136%. The results varied, however, according to the type of fungi evaluated. Decay fungi and sap-stain fungi elicited positive responses in termites, whereas molds did not affect the consumption of cellulose by termites. Amongst the decay fungi group, white-rot fungi caused the strongest and most positive response in all termite behaviors evaluated, although brown-rot fungi is known to be preferred by termites. The results of our study, therefore, suggest that wood-inhabiting fungi are potential facilitators of the foraging behavior and survivorship of termites. These results have great implications for termite biocontrol, as well as for knowledge of the ecological aspects of termite–fungi interactions.     

Biology of gut anaerobic fungi

The obligately anaerobic nature of the gut indigenous fungi distinguishes them from other fungi. They are distributed widely in large herbivores, both in the foregut of ruminant-like animals and in the hindgut of hindgut fermenters. Comparative studies indicate that a capacious organ of fermentative digestion is required for their development. These fungi have been assigned to the Neocallimasticaceae, within the chytridiomycete order Spizellomycetales. The anaerobic fungi of domestic ruminants have been studied most extensively. Plant material entering the rumen is rapidly colonized by zoospores that attach and develop into thalli. The anaerobic rumen fungi have been shown to produce active cellulases and xylanases and specifically colonise and grow on plant vascular tissues. Large populations of anaerobic fungi colonise plant fragment in the rumens of cattle and sheep on high-fibre diets. The fungi actively ferment cellulose which results in formation of a mixture of products including acetate, lactate, ethanol, formate, succinate, CO2 and H2. The properties of the anaerobic fungi together with the extent of their populations on plant fragments in animals on high-fibre diets indicates a significant role for the fungi in fibre digestion.     

Ambrosia fungi in the insect-fungi symbiosis in relation to cork oak decline

Ambrosia fungi live associated with beetles (Scolytidae and Platypodidae) in host trees and act as a food source for the insects. The symbiotic relation is important to the colonizing strategies of host trees by beetles. Ambrosia fungi are dimorphic: they grow as ambrosial form and as mycelium. The fungi are highly specialized, adapted to a specific beetle and to the biotope where they both live. In addition other fungi have been found such as tree pathogenic fungi that may play a role in insects host colonization success. Saprophytic fungi are also present in insects galleries. These may decompose cellulose and/or be antagonistic to other less beneficial fungi. This paper summarizes the importance of ambrosia fungi and the interaction with insects and hosts. The possibility of the transport of pathogenic fungi by Platypus cylindrus to cork oak thus contributing for its decline is discussed.     

Invasion potential and host shifts of Australian and African ectomycorrhizal fungi in mixed eucalypt plantations

? Transportation of forestry materials results in unintended co-introduction of nonnative species that may cause enormous ecological or economic damage. While the invasion ecology of plants and animals is relatively well-known, that of microorganisms, except aboveground pathogens, remains poorly understood. ? This work addresses host shifts and invasion potential of root symbiotic ectomycorrhizal fungi that were co-introduced with Australian eucalypts and planted in clear-cut miombo woodlands in Zambia, south-central Africa. ? By use of rDNA and plastid intron sequence analysis for identification and phylogenetic techniques for inferring fungal origin, we demonstrated that host shifts were uncommon in the Australian fungi, but frequent in the African fungi, especially in mixed plantations where roots of different trees intermingle. ? There was evidence for naturalization, but not for invasion by Australian ectomycorrhizal fungi. Nevertheless, the fungi introduced may pose an invasion risk along with further adaptation to local soil environment and host trees. Inoculation of eucalypts with native edible fungi may ameliorate the potential invasion risks of introduced fungi and provide an alternative source of nutrition.     

Thermophilic fungi: their physiology and enzymes.

Thermophilic fungi are a small assemblage in mycota that have a minimum temperature of growth at or above 20 degrees C and a maximum temperature of growth extending up to 60 to 62 degrees C. As the only representatives of eukaryotic organisms that can grow at temperatures above 45 degrees C, the thermophilic fungi are valuable experimental systems for investigations of mechanisms that allow growth at moderately high temperature yet limit their growth beyond 60 to 62 degrees C. Although widespread in terrestrial habitats, they have remained underexplored compared to thermophilic species of eubacteria and archaea. However, thermophilic fungi are potential sources of enzymes with scientific and commercial interests. This review, for the first time, compiles information on the physiology and enzymes of thermophilic fungi. Thermophilic fungi can be grown in minimal media with metabolic rates and growth yields comparable to those of mesophilic fungi. Studies of their growth kinetics, respiration, mixed-substrate utilization, nutrient uptake, and protein breakdown rate have provided some basic information not only on thermophilic fungi but also on filamentous fungi in general. Some species have the ability to grow at ambient temperatures if cultures are initiated with germinated spores or mycelial inoculum or if a nutritionally rich medium is used. Thermophilic fungi have a powerful ability to degrade polysaccharide constituents of biomass. The properties of their enzymes show differences not only among species but also among strains of the same species. Their extracellular enzymes display temperature optima for activity that are close to or above the optimum temperature for the growth of organism and, in general, are more heat stable than those of the mesophilic fungi. Some extracellular enzymes from thermophilic fungi are being produced commercially, and a few others have commercial prospects. Genes of thermophilic fungi encoding lipase, protease, xylanase, and cellulase have been cloned and overexpressed in heterologous fungi, and pure crystalline proteins have been obtained for elucidation of the mechanisms of their intrinsic thermostability and catalysis. By contrast, the thermal stability of the few intracellular enzymes that have been purified is comparable to or, in some cases, lower than that of enzymes from the mesophilic fungi. Although rigorous data are lacking, it appears that eukaryotic thermophily involves several mechanisms of stabilization of enzymes or optimization of their activity, with different mechanisms operating for different enzymes.     

Volatile-mediated antagonism of soil bacterial communities against fungi

Competition is a major type of interaction between fungi and bacteria in soil and is also an important factor in suppression of plant diseases caused by soil-borne fungal pathogens. There is increasing attention for the possible role of volatiles in competitive interactions between bacteria and fungi. However, knowledge on the actual role of bacterial volatiles in interactions with fungi within soil microbial communities is lacking. Here, we examined colonization of sterile agricultural soils by fungi and bacteria from non-sterile soil inoculums during exposure to volatiles emitted by soil-derived bacterial communities. We found that colonization of soil by fungi was negatively affected by exposure to volatiles emitted by bacterial communities whereas that of bacteria was barely changed. Furthermore, there were strong effects of bacterial community volatiles on the assembly of fungal soil colonizers. Identification of volatile composition produced by bacterial communities revealed several compounds with known fungistatic activity. Our results are the first to reveal a collective volatile-mediated antagonism of soil bacteria against fungi. Given the better exploration abilities of filamentous fungi in unsaturated soils, this may be an important strategy for bacteria to defend occupied nutrient patches against invading fungi. Another implication of our research is that bacterial volatiles in soil atmospheres can have a major contribution to soil fungistasis.     

Evolutionary histories and mycorrhizal associations of mycoheterotrophic plants dependent on saprotrophic fungi

Mycoheterotrophic plants (MHPs) are leafless, achlorophyllous, and completely dependent on mycorrhizal fungi for their carbon supply. Mycorrhizal symbiosis is a mutualistic association with fungi that is undertaken by the majority of land plants, but mycoheterotrophy represents a breakdown of this mutualism in that plants parasitize fungi. Most MHPs are associated with fungi that are mycorrhizal with autotrophic plants, such as arbuscular mycorrhizal (AM) or ectomycorrhizal (ECM) fungi. Although these MHPs gain carbon via the common mycorrhizal network that links the surrounding autotrophic plants, some mycoheterotrophic lineages are associated with saprotrophic (SAP) fungi, which are free-living and decompose leaf litter and wood materials. Such MHPs are dependent on the forest carbon cycle, which involves the decomposition of wood debris and leaf litter, and have a unique biology and evolutionary history. MHPs associated with SAP fungi (SAP-MHPs) have to date been found only in the Orchidaceae and likely evolved independently at least nine times within that family. Phylogenetically divergent SAP Basidiomycota, mostly Agaricales but also Hymenochaetales, Polyporales, and others, are involved in mycoheterotrophy. The fungal specificity of SAP-MHPs varies from a highly specific association with a single fungal species to a broad range of interactions with multiple fungal orders. Establishment of symbiotic culture systems is indispensable for understanding the mechanisms underlying plant–fungus interactions and the conservation of MHPs. Symbiotic culture systems have been established for many SAP-MHP species as a pure culture of free-living SAP fungi is easier than that of biotrophic AM or ECM fungi. Culturable SAP-MHPs are useful research materials and will contribute to the advancement of plant science.

     

Variation in mycorrhizal growth response influences competitive interactions and mechanisms of plant species coexistence

Plant species vary in their growth response to arbuscular mycorrhizal (AM) fungi, with responses ranging from negative to positive. Differences in response to AM fungi may affect competition between plant species, influencing their ability to coexist. We hypothesized that positively responding species, whose growth is stimulated by AM fungi, will experience stronger intraspecific competition and weaker interspecific competition in soil containing AM fungi, while neutrally or negatively responding species should experience weaker intraspecific and stronger interspecific competition. We grew Plantago lanceolata, which responds positively to AM fungi, and Bromus inermis, which responds negatively to AM fungi, in an additive response surface competition experiment that varied the total density and relative frequency of each species. Plants were grown in sterilized background soil that had been inoculated with whole soil biota, which includes AM fungi, or a microbial wash, that contained other soil microbes but no AM fungi, or in sterilized soil that contained no biota. The positively responding P. lanceolata was more strongly limited by intraspecific than interspecific competition when AM fungi were present. By contrast, the presence of AM fungi decreased the strength of intraspecific competition experienced by the negatively responding B. inermis. Because AM fungi are almost always present in soil, strong intraspecific competition in positively responding species would prevent them from outcompeting species that respond neutrally or negatively to AM fungi. The potential for increased intraspecific competition to offset growth benefits of AM fungi could, therefore, be a stabilizing mechanism that promotes coexistence among plant species.     

丝状真菌的细胞凋亡

凋亡是一种程序性细胞死亡类型,为多细胞生物发育和维持生命所必需的,也普遍存在于细菌等原核生物和酵母、丝状真菌等真核生物中。丝状真菌既具有酵母和哺乳动物共有的凋亡同源蛋白,也具有酵母所不具备的哺乳动物凋亡同源蛋白,所以其凋亡机制较酵母更为复杂,而又较哺乳动物简单。凋亡在丝状真菌的发育、繁殖、衰老等过程中具有重要的作用。近年,丝状真菌作为新的凋亡研究的模式生物被广泛研究,而且进展迅速。综述丝状真菌的凋亡现象和检测方法,丝状真菌中凋亡的生物学功能,丝状真菌凋亡的诱导条件,以及丝状真菌凋亡相关基因的功能研究进展。     

Pathogenesis-related genes of entomopathogenic fungi

All living things on Earth experience various diseases such as those caused by viruses, bacteria, and fungi. Insects are no exception to this rule, and fungi that cause disease in insects are called entomopathogenic fungi. These fungi have been developed as microbial insecticides and are used to control various pests. Generally, the mode of action of entomopathogenic fungi is divided into the attachment of conidia, germination, penetration, growth, and generation of secondary infectious conidia. In each of these steps, that entomopathogenic fungi use genes in a complex manner (specific or diverse) has been shown by gene knock-out and RNA-sequencing analysis. In this review, the information mechanism of entomopathogenic fungi was divided into six steps: (1) attachment of conidia to host, (2) germination and appressorium, (3) penetration, (4) fungal growth in hemolymph, (5) conidia production on host, and (6) transmission and dispersal. The strategy used by the fungi in each step was described at the genetic level. In addition, an approach for studying the mode of action of the fungi is presented.     

Are white-rot fungi a real biotechnological option for the improvement of environmental health?

The use of white-rot fungi as a biotechnological tool for cleaning the environment of recalcitrant pollutants has been under evaluation for several years. However, it is still not possible to find sufficiently detailed investigations of this subject to conclude that these fungi can decontaminate the environment. In the present review, we have summarized and discussed evidence about the potential of white-rot fungi to degrade such pollutants as polycyclic aromatic hydrocarbons, dyes or antibiotics as an example of the complex structures that these microorganisms can attack. This review also discusses field experiment results and limitations of white-rot fungi trials from contaminated sites. Moreover, the use of catabolic potential of white-rot fungi in biopurification systems (biobeds) is also discussed. The current status and future perspectives of white-rot fungi, as a viable biotechnological alternative for improvement of environmental health are noted.     

Mycorrhizal fungi of Vanilla: diversity, specificity and effects on seed germination and plant growth

Mycorrhizal fungi are essential for the germination of orchid seeds. However, the specificity of orchids for their mycorrhizal fungi and the effects of the fungi on orchid growth are controversial. Mycorrhizal fungi have been studied in some temperate and tropical, epiphytic orchids, but the symbionts of tropical, terrestrial orchids are still unknown. Here we study diversity, specificity and function of mycorrhizal fungi in Vanilla, a pantropical genus that is both terrestrial and epiphytic. Mycorrhizal roots were collected from four Vanilla species in Puerto Rico, Costa Rica and Cuba. Cultured and uncultured mycorrhizal fungi were identified by sequencing the internal transcribed spacer region of nuclear rDNA (nrITS) and part of the mitochondrial ribosomal large subunit (mtLSU), and by counting number of nuclei in hyphae. Vanilla spp. were associated with a wide range of mycorrhizal fungi: Ceratobasidium, Thanatephorus and Tulasnella. Related fungi were found in different species of Vanilla, although at different relative frequencies. Ceratobasidium was more common in roots in soil and Tulasnella was more common in roots on tree bark, but several clades of fungi included strains from both substrates. Relative frequencies of genera of mycorrhizal fungi differed significantly between cultured fungi and those detected by direct amplification. Ceratobasidium and Tulasnella were tested for effects on seed germination of Vanilla and effects on growth of Vanilla and Dendrobium plants. We found significant differences among fungi in effects on seed germination and plant growth. Effects of mycorrhizal fungi on Vanilla and Dendrobium were similar: a clade of Ceratobasidium had a consistently positive effect on plant growth and seed germination. This clade has potential use in germination and propagation of orchids. Results confirmed that a single orchid species can be associated with several mycorrhizal fungi with different functional consequences for the plant.     

Saprotrophic capabilities as functional traits to study functional diversity and resilience of ectomycorrhizal community

In an accompanying editorial Dr Petr Baldrian made a case casting doubt on our recent work addressing the saprophytic potential of ectomycorrhizal (EM) fungi. Dr Baldrian’s statements illustrate a very valid truth: the book is still very much open on this subject. The point he raised that the only logical reason for these fungi to be responding to high carbon demand or decreased host photosynthetic capacity by up-regulating enzymes is for the purpose of carbon acquisition is valid as well. Despite this, he makes the case that there is no compelling evidence that EM fungi exhibit saprophytic activity. The concept central to Dr Baldrian’s conclusion is that even though some EM fungi possess the genes necessary for saprophytic behaviour and may even express these genes, EM fungi do not inhabit a position in the soil column that provides access to usable substrate. In this paper we present both previously published and newly obtained data that demonstrate that this assumption is erroneous, and we present arguments that place the saprophytic potential of EM fungi within a broad ecological context.     

Development of new tools for studying gene function in fungi based on the Gateway system

Genomic information of many fungi has been released but large scale functional genomic studies are still limited by a lack of high-throughput methods. The low rates of homologous recombination and low rates of transformation are limiting steps in filamentous fungi, but the molecular tools are also lagging behind. In this paper we describe two new high-throughput functional genomic tools for filamentous fungi that are based on the Gateway technology. One system is the Gateway RNAi vector for fungi that allows gene silencing in a high-throughput manner. The other system is a high-throughput deletion construct system. These systems were tested using the PAC1 gene of Colletotrichum gloeosporioides. Using these types of approaches, large scale functional genomics experiments can be performed in filamentous fungi.     

真菌N-糖基化系统在异源表达中的研究进展

在近20年来,越来越多的真菌被开发成异源蛋白表达宿主,用来生产各种药用蛋白和酶类。随着对真菌异源表达系统的研究,人们也渐渐意识到真菌N-糖基化系统与高等动物的N-糖基化系统有着明显的区别,这也成为真菌生产高等动物源性糖蛋白的一个技术瓶颈。本文综述了真菌在异源表达糖蛋白工程中其N-糖基化系统的研究进展。包括N-糖基的检测技术和改造策略,并重点介绍了真菌N-糖基化系统与高等动物的N-糖基化系统的差异,以期为日后真菌N-糖基化系统动物源化甚至人源化改造提供参考。     

How many fungi make sclerotia?

Most fungi produce some type of durable microscopic structure such as a spore that is important for dispersal and/or survival under adverse conditions, but many species also produce dense aggregations of tissue called sclerotia. These structures help fungi to survive challenging conditions such as freezing, desiccation, microbial attack, or the absence of a host. During studies of hypogeous fungi we encountered morphologically distinct sclerotia in nature that were not linked with a known fungus. These observations suggested that many unrelated fungi with diverse trophic modes may form sclerotia, but that these structures have been overlooked. To identify the phylogenetic affiliations and trophic modes of sclerotium-forming fungi, we conducted a literature review and sequenced DNA from fresh sclerotium collections. We found that sclerotium-forming fungi are ecologically diverse and phylogenetically dispersed among 85 genera in 20 orders of Dikarya, suggesting that the ability to form sclerotia probably evolved ≥14 different times in fungi.     

The siderophore ferricrocin produced by specific foliar endophytic fungi in vitro

Production of extracellular siderophores is typical for many plant-associated microbes, both mutualistic and antagonistic. Various strains of mycorrhizal fungi produce siderophores, and siderophore production by pathogenic fungi is typically associated with virulence. We analyzed extracellular siderophore production along with production of antibacterial and antioxidant compounds in foliar endophytic fungi of Scots pine (Pinus sylvestris L.) and Labrador tea (Rhododendron tomentosum Harmaja). The siderophore produced in vitro was ferricrocin, quantities ranging between 7.9 and 17.6 μg/l. Only the fungi with antibacterial activity produced ferricrocin and any well-known siderophores were not detected in the broths of antioxidant-producing fungi. Therefore, production of ferricrocin is typical for some, but not all foliar endophytic fungi. Ferricrocin was detected in the leaves of Labrador tea, which suggests that ferricrocin may play a role in vivo in the interaction between the endophyte and plant host.