Truffles and tulips: Pensoft and the 12th International Mycological Congress

Over 1,000 fungi enthusiasts gathered in Maastricht for the biggest mycology event of the year.

The Pensoft team had a fantastic time at the 12th International Mycological Congress in Maastricht, the Netherlands.

Organised by the International Mycological Association, together with the Dutch Mycological Society and the Westerdijk Fungal Biodiversity Institute, the four-day meeting saw around 1,400 fungi fanatics gather for the biggest mycology event of the year.

It all began with an opening ceremony complete with live music and stunning visuals, which set the stage for five days of research exchange and collaboration.

Pensoft welcomed faces new and old at a decorated stand featuring numerous illustrated materials designed by scientific illustrator Denitsa Peneva. Manning the stand were Prof Dr Lyubomir Penev (MycoKeys Founding Editor & Pensoft Founder and CEO) and Slavena Peneva (Pensoft Head of Graphic Design).

The booth hosted a special gathering for MycoKeys editors, including Editor-in-Chief Prof Dr Thorsten Lumbsch, who were shown a video looking back on the history of the journal. Many long-time collaborators of Pensoft, such as Prof Dr Urmas Kõljalg of Pluto F and Dr Dmitry Schigel of Pluto F, also dropped by to say hello.

The congress provided the perfect opportunity to announce Pensoft’s new, exciting partnership with the International Mycological Association. This collaboration will see the IMAFungus journal move to the ARPHA platform, where it will benefit from cutting-edge publishing technology and workflows.

Several MycoKeys contributors presented and hosted keynote lectures, bridging sessions, and workshops across the seven major topics of the conference:

  • Cell biology, biochemistry and physiology
  • Environment, ecology and interactions
  • Evolution, biodiversity and systematics
  • Fungal pathogenesis and disease control
  • Genomics, genetics and molecular biology
  • Applied Mycology
  • Nomenclature

The full program can be found on the congress website.

The next International Mycology Congress will be held in Incheon, South Korea, in 2027. IMC13 already has an active website and the Pensoft team look forward to another exciting installment!

***

Follow Pensoft on social media:

Do all fungi matter? Yes, new study argues

Fungi that do not form fruiting bodies and that we cannot grow in the laboratory cannot be given scientific names. Does it make sense to ignore them?

Mention fungi, and most people will probably think of the mushrooms they pick in fall, or maybe the yeast they add when baking or making wine. Others will perhaps recall last week’s mouldy bread – or cucumbers gone bad in the refrigerator. Indeed, mycologists have studied these fungi as sources of food and fermentation but also decay and disease for centuries.

Sampling soil and sediments for fungal diversity not far from Göteborg, Sweden. Photo by Henrik Nilsson

But while we’re used to thinking of fungi as organisms that form physical structures such as fruiting bodies, or yeast-like life forms that we can grow in our kitchens or laboratories, it is gradually becoming clear that fungi don’t readily assort into only these two groups. DNA sequencing studies of environmental substrates such as soil are finding massive evidence of large groups of fungi that do not seem to form fruiting bodies and that we seem unable to grow in the lab – but that are there nonetheless. These groups are often called “dark fungi,” in analogy with the concept of “dark matter” in astronomy – something we know is out there, but that we cannot directly observe right now.

A new study in MycoKeys contrasts the accumulation of fungal species recovered using traditional mycological approaches with those recovered using environmental DNA sequencing over time. Even when allowing for various kinds of biases, the authors found that species discovery through environmental sequencing vastly outpaces traditional species recovery in a strongly increasing trend over the last five years. The authors conclude that dark fungi form a defining feature of the fungal kingdom.

Field work on the Tibetan Plateau. Photo by Wengang Kang

“And that’s where it gets interesting”, Henrik Nilsson at the University of Gothenburg, Sweden, and the lead author of the study, says. “Under the current rules of nomenclature, these fungi cannot be given scientific names – they cannot be described formally. And species and groups that cannot be named formally, well, they tend to fall between the cracks. They’re typically not considered in nature conservation initiatives. They are often left out from efforts to estimate the evolutionary history of fungi, and their ecological roles and associations are largely overlooked when we try to figure out how mass and energy flow in ecosystems. They’re essentially treated as if they didn’t exist.”

Examining minute fungal fruiting bodies not far from Stockholm, Sweden. Photo by Kristina Stenmarck

Second author Martin Ryberg at the University of Uppsala, Sweden chimes in, “And it’s not like we’re adding the few missing pieces to an otherwise nearly complete jigsaw puzzle. It seems to be the other way around. We’re talking about tens of large groups of fungi – and thousands upon thousands of species, some of which seem to be so common that we have yet to find a soil sample from which they’re absent. Indeed, we’re talking about what could well prove to be the dominant life style in the fungal kingdom.”

The mycological community has been debating whether the rules of fungal nomenclature should be modified to allow formal description of these dark fungi. So far, the matter has not been resolved in the affirmative. “I think our study shows that it’s time to stop that debate, like, right away,” Nilsson says. “What we should be debating is how we should describe them. What criteria must be fulfilled for a dark fungus to be given a formal scientific name? Clearly, formation of a fruiting body or growth in the laboratory can’t be part of those criteria.”

Field work in New Caledonia. Photo by Sten Anslan

Co-author Alice Retter of the University of Vienna, Austria explains, “We figured we’d kickstart the how debate by listing criteria that we think make sense – criteria that would be stringent enough to allow for only particularly well-vetted dark fungi to be described, upholding a high level of scientific rigor and reproducibility in the process. We blended our own observations with suggestions from the mycological community, culled from depositing a preprint of the manuscript at bioRxiv. We’re certainly not claiming that our suggestions form the final word in the debate. It’s more like they’re the first. We’re thinking that the mycological community will jointly be able to come up with a set of sound guiding principles on the matter – and here comes an initial set of well-meaning observations for nucleation.”

Field work in the German Alps. Photo by Vanessa Schulz

The authors advocate gentle modifications to the nomenclatural rules governing the naming of fungi to allow giving formal names to at least the most well-documented species and groups of dark fungi. The suggested modifications would, at present, exclude many rare or otherwise less well-documented dark fungi from formal description.

“But you don’t have to have a theory of everything to have a theory of something,” senior author Kessy Abarenkov of the Tartu Natural History Museum, Estonia asserts. “By establishing rules for what’s needed to describe dark fungi, and specifying when we’ll have to refrain from describing such species at present, mycologists can do what they do best: doggedly gather enough research data to warrant naming of the dark fungi, group by group, and species by species. It’s what mycology has excelled at for hundreds of years. It’s just the setting that’s a bit new.”

Drying soil samples immediately upon collection under field conditions in Norway. Photo by Sten Anslan

Sten Anslan, University of Tartu, continues: “Much is at stake, obviously. The current rules governing the naming of fungi have served mycology well for a long time. We don’t want to upend or overthrow them. But we fear that if they’re not updated in this particular regard, there’s a risk that they grow increasingly obsolete over time. Having a book of rules that govern maybe only some few percent of the organisms it was originally conceived to govern – the fungal kingdom – would seem untenable in the long run.”

Getting ready for DNA extraction from soil samples. Photo by Sten Anslan

Marisol Sanchez-Garcia of the Swedish Agricultural University concludes: “The nomenclatural aspects of dark fungi will presumably be discussed at some length at next year’s international mycological congress in Maastricht, the Netherlands. We’re hopeful that the mycological community will reach meaningful agreement on integration of the dark fungi into the rules of nomenclature. After all, mycologists are used to negotiating and solving non-trivial questions on a day-to-day basis, and this one is hardly any different. Being part of tackling a huge, more or less unknown group of organisms where precious little is set in stone and where the rules will have to be adapted over time for the endeavour to stay attuned to recent developments, well, that’s what makes being a mycologist so interesting and rewarding in my eyes.”

Research article:

Nilsson RH, Ryberg M, Wurzbacher C, Tedersoo L, Anslan S, Põlme S, Spirin V, Mikryukov V, Svantesson S, Hartmann M, Lennartsdotter C, Belford P, Khomich M, Retter A, Corcoll N, Gómez Martinez D, Jansson T, Ghobad-Nejhad M, Vu D, Sanchez-Garcia M, Kristiansson E, Abarenkov K (2023) How, not if, is the question mycologists should be asking about DNA-based typification. MycoKeys 96: 143-157. https://doi.org/10.3897/mycokeys.96.102669

Cultivated and wild bananas in northern Viet Nam threatened by а devastating fungal disease

For over 100 years, Fusarium, one of the most important fungal plant pathogens, has affected banana production worldwide.

Fusarium is one of the most important fungal plant pathogens, affecting the cultivation of a wide range of crops. All over the world, thousands of farmers suffer agricultural losses caused by Fusarium oxysporum f. sp. cubense (referred to as Foc for short), which directly affects their income, subsistence, and nourishment.

As a soil-borne fungus, Foc invades the root system, from where it moves into the vascular tissue that gradually deteriorates, until eventually the plant dies. What makes it particularly hard to deal with is that, even 20 years after all infected plants and tissue are removed, spores of it still remain in the soil.

One industry significantly affected by Foc is global banana export, largely dependent on the cultivation of members of the Cavendish subgroup, which are highly susceptible to some of the Foc strains.

For over 100 years, the fungus has affected banana production worldwide. Researchers predict it will continue spreading intensively in Asia, affecting important banana-producing countries such as China, the Philippines, Pakistan, and Viet Nam.

For Viet Nam, predictions on the impact of Foc for the future are dramatic: an estimated loss in the banana production area of 8% within the next five years, and up to 71% within the next 25 years. In particular, the recent rise of the novel TR4 strain has resulted in worldwide anxiety about the future of the well-known Cavendish banana and many other cultivars. Fusarium oxysporum f. sp. cubense is, however, not limited to TR4 or other well-known strains, like Race 1 or Race 2; it is a species complex that plant pathologists are yet to fully disentangle. 

In Viet Nam, like in the rest of Asia, Africa, Latin America, and the Caribbean, most bananas are consumed and traded locally, supporting rural livelihood. This means that any reduction in crop harvest directly affects local people’s income and nourishment. 

It has thus become necessary to find out what are the individual species causing the Fusarium wilt among Vietnamese bananas. Only by understanding which species are infecting the cultivated bananas can concrete measures be taken to control the future spreading of the disease to other regions.

Using DNA analyses and morphological characterization, an international team of researchers from Viet Nam (Plant Resources Center, Vietnam National University of Agriculture), Belgium (Meise Botanic Garden, KU Leuven, Bioversity Leuven, MUCL) and the Netherlands (Naturalis Biodiversity Center) investigated the identity of the Fusarium wilt infections. They recently published their joint research in the open-access, peer-reviewed journal MycoKeys.

The study shows that approximately 3 out of 4 Fusarium infections of the northern Vietnamese bananas are caused by the species F. tardichlamydosporum, which can be regarded as the typical Race 1 infections. Interestingly, Foc TR4 is not yet a dominant strain in northern Viet Nam, as the species causing the disease – F. odoratissimum – only accounts for 10% of the Fusarium infections. A similar proportion of Fusarium infections is caused by the species Fusarium cugenangense – considered to cause Race 2 infections among bananas.More importantly, Fusarium wilt was not only found in cultivated bananas: the disease seemed to also affect wild bananas. This finding indicates that wild bananas might function as a sink for Fusarium wilt from where reinfections towards cultivars could take place.

Research article:

Le Thi L, Mertens A, Vu DT, Vu TD, Anh Minh PL, Duc HN, de Backer S, Swennen R, Vandelook F, Panis B, Amalfi M, Decock C, Gomes SIF, Merckx VSFT, Janssens SB (2022) Diversity of Fusarium associated banana wilt in northern Viet Nam. MycoKeys 87: 53-76. https://doi.org/10.3897/mycokeys.87.72941

Lifting the veil over mysterious desert truffles: Terfezia’s ecology and diversity towards cultivation

Developing below the soil surface, desert truffles are hard to find. Recently, researchers of the University of Évora updated the number of known species of the desert truffle genus Terfezia occurring in Portugal from three to ten species. They thoroughly characterized their ecological preferences, adding new knowledge on Terfezia’s cryptic lifestyle. These findings are of major importance, as desert truffles have a high economic value. The study was published in the open-access journal MycoKeys.

In a caring, symbiotic relationship, mycorrhizal fungi live and feed in the roots of specific plants, while providing water and nutrients to their ‘companion’. In arid and semi-arid environments, mycorrhization processes are essential to the survival of both plants and fungi. Moreover, the fungus’ hyphal network, which spreads within the soil connecting several plant individuals, is of utmost importance to enhancing soil quality and fertility.

Researchers of the University of Évora in Portugal, led by biologist Celeste Santos e Silva, worked on Terfezia fungi, the most diverse and species-rich genus among desert truffles. Their study, published in the open-access journal MycoKeys, might prove particularly valuable to rural populations in the Mediterranean basin, where desert truffles, highly valued in local markets, are an important food source. Increasingly turning into an exquisite component of the Mediterranean diet, Terfezia products can also be very profitable. Furthermore, these fungi are essential for soil conservation, preventing erosion and desertification.

Desert truffles.

After 8 years of exhaustive field exploration in search of desert truffles and many hours in the molecular biology lab, the researchers noted some previously unknown trends in the ecology of Terfezia species. They recorded seven species that were new to Portugal, including two that are new to science – Terfezia lusitanica and Terfezia solaris-libera. This brings the number of Terfezia species known to be growing in the country to ten. Particularly important was the discovery of a broader ecological range for many of the studied species (e.g. Terfezia grisea). Adding valuable information about their possible hosts, symbionts and ecological constraints, these findings help open new opportunities for truffle cultivation.

“It is very difficult to identify all specimens given that the Terfezia species look so much alike, and molecular biology was absolutely fundamental here”, explains the researcher. “The technique was essential to update and solve problems about their taxonomy and the relationship between the species in the genus.”

Furthermore, the discoveries are also expected to positively impact the local communities by stimulating agriculture produce, business and even employment. 

Desert truffle production explained. Video by University of Évora

Knowledge gained in this research about the conditions in which different Terfezia species grow is an important step to desert truffle cultivation: the fungi are hard to find in the wild, which is why it would make a big difference – including financially – for local communities if they figure out a way to grow truffles themselves.

Within the project “Mycorrhization of Cistus spp with Terfezia arenaria (Moris) Trappe and its application in the production of desert truffles” (ALT20-03-0145-FEDER-000006), the researchers took a step forward towards achieving mycorrhizal association of desert truffles with perennial plants (rock roses), which would allow their mass production for various sectors such as food, medicine and soil recovery. This new form of production, assures the MED researcher and leader of the project, “will make it possible to create more jobs, reversing the current trend towards desertification in rural areas, while being a great tool for ecosystem recovery and restoration”.

Research article:


Santos-Silva C, Louro R, Natário B, Nobre T (2021) Lack of knowledge on ecological determinants and cryptic lifestyles hinder our understanding of Terfezia diversity. MycoKeys 84: 1-14. https://doi.org/10.3897/mycokeys.84.71372

New pathogen threatens fennel yield in Italy

A new fungal genus and species Ochraceocephala foeniculi causes fennel yield losses of about 20-30% for three different cultivars. It damages the crops with necrotic lesions on the crown, root and stem.
International research group makes the first step in handling the new fennel disease by publishing their paper in the open-access journal Mycokeys.

A new fennel fungal disease caused by a new genus and species – Ochraceocephala foeniculi, was observed for the first time in 2017 on 5% of the “Apollo” fennel cultivar grown in the sampled localities in Catania province, Italy. Now, it has spread to 2 more cultivars: “Narciso” and “Pompeo”, causing crop losses of around 20-30%. The new pathogen damages the fennel with necrotic lesions on the crown, root and stem.

Fennel, a crop native in arid and semi-arid regions of southern Europe and the Mediterranean area is massively used as a vegetable, herb and seed spice in food, pharmaceutical, cosmetic and healthcare industries with Italy taking the world-leading production. It is an important and widely cultivated crop in Sicily (southern Italy).

Symptoms caused by Ochraceocephala foeniculi on fennel plants
Symptoms caused by Ochraceocephala foeniculi on fennel plants
Credits: Dalia Aiello
License: CC-BY 4.0

Worldwide, fennel crops are affected by several fungal diseases. In Italy, amongst soilborne diseases, there have been reports of brown rot and wilt caused by Phytophthora megasperma and crown rot caused by Didymella glomerata.

International research group, led by Ms. Dalia Aiello from the University of Catania, made the first step in handling the new fennel disease by identifying the causal agent obtained from symptomatic plants and publishing the results of their research in the open-access journal Mycokeys.

In order to understand the origin of the causal agent, scientists collected 30 samples during several surveys in the affected areas in Sicily, and studied the consistently grown fungal colonies from symptomatic tissues.

“The fungal species obtained from symptomatic tissues was identified based on morphological characters and molecular phylogenetic analyses of an ITS-LSU-SSU rDNA matrix, resulting in the description of the fennel pathogen as a new genus and species, Ochraceocephala
foeniculi,”

shares Dr. Dalia Aiello.

According to the pathogenicity tests, O. foeniculi causes symptoms on artificially inoculated plants of the same cultivar. Preliminary evaluation of fennel germplasm, according to the susceptibility to the new disease, shows that some cultivars (“Narciso”, “Apollo” and “Pompeo”) are more susceptible and some are less susceptible (“Aurelio”, “Archimede” and “Pegaso”), but this is a subject yet to be confirmed by additional investigations. More studies are required in order to plan further effective disease management strategies.

Holotype of Ochraceocephala foeniculi
Credits: Mr. Hermann Voglmayr
License: CC-BY 4.0

“On the basis of the disease incidence and severity observed in the field, we believe that this disease represents a serious threat to fennel crop in Sicily and may become a major problem also to other areas of fennel production if accidentally introduced,”

concludes Dr. Dalia Aiello.
***

Original source: Aiello D, Vitale A, Polizzi G, Voglmayr H (2020) Ochraceocephala foeniculi gen. et sp. nov., a new pathogen causing crown rot of fennel in Italy. MycoKeys 66: 1-22. https://doi.org/10.3897/mycokeys.66.48389

Medicinal mushroom newly reported from Thailand helps reveal optimum growth conditions

Globally recognised medicinal mushroom is reported for the first time in Thailand. The study also presents the first assessment of the optimum growth conditions for the species.

A species of globally recognised medicinal mushroom was recorded for the first time in Thailand. Commonly referred to as lingzhi, the fungus (Ganoderma tropicum) was collected from the base of a living tree in Chiang Rai Province, Northern Thailand. Additionally, the study reports the first assessment of the optimum conditions needed for the species to grow its mycelia (the vegetative part of a fungus consisting of a branching network of fine, thread-like structures) and spread its colony.

The discoveries are published in the open-access journal MycoKeys by a research team from the Chinese Academy of Sciences, University of Chinese Academy of SciencesWorld Agroforestry CentreKunming Institute of Botany (China) and Center of Excellence in Fungal ResearchMae Fah Luang University (Thailand), led by Thatsanee Luangharn.

Over the last centuries, the studied mushroom and its related species in the genus Ganoderma have been used extensively in traditional Asian medicines due to their natural bioactive compounds, including polysaccharides, triterpenoids, sterols, and secondary metabolites, which are used in the treatment of various diseases. Other compounds derived from lingzhi, such as the studied species, also demonstrate antimicrobial activities. The medicinal use of these mushrooms is recognised by the World Health Organization and they are featured in the Chinese Pharmacopoeia.

The studied mushroom belongs to a group known to be parasitic or pathogenic on a wide range of tree species. The species is characterised with strongly laccate fruiting bodies and a cap with distinctly dark brown base colour and reddish shades. It grows to up to 7-12 cm in length, 4-8 cm in width and is up to 1.5 cm thick. While the mushroom has so far been widely reported from tropical areas, including mainland China, Taiwan and South America, it had never been recorded from Thailand.

During their research, the scientists found that mycelial production for Ganoderma tropicum is most successful on Potato Dextrose Agar, Malt Extract Agar, and Yeast extract Peptose Dextrose Agar, at a temperature of 25-28 °C and 7-8 pH. Unfortunately, mushroom fruiting was not achieved in the experiment.

###

Original source:

Luangharn T, Karunarathna SC, Mortimer PE, Hyde KD, Thongklang N, Xu J (2019) A new record of Ganoderma tropicum (Basidiomycota, Polyporales) for Thailand and first assessment of optimum conditions for mycelia production. MycoKeys 51: 65-83. https://doi.org/10.3897/mycokeys.51.33513

New family of fungi threatens a UNESCO-listed 8-century-old cathedral in Portugal

The Old Cathedral of Coimbra [right], the Santa Maria chapel [left, top] and the artwork from which the scientists retrieved the studied fungi [left, bottom]. Photo by Miguel Mesquita.
To be listed as UNESCO World Heritage requires special care and protection of valuable cultural monuments and pieces of Art from threats such as biodeterioration caused by microcolonial black fungi. The culprits lodge their branch-like structures (hyphae) deep into the stone forming fissures and cracks and also produce polysaccharides that trigger corrosion.

These fungi are well known for their unique resistance to hostile environmental conditions, including extreme temperatures, high solar and UV radiation, severe droughts and low abundance of nutrients. As a result, they survive in hot and cold deserts, saltpans, acidic and hydrocarbon-contaminated sites and exposed rocks surfaces. All of this makes them a particular challenge to conservationists and biologists who care for historic monuments.

During a multi-disciplinary scientific survey at the 8-century-old cathedral Sé Velha de Coimbra (Old Cathedral of Coimbra), which is the only Romanesque cathedral in Portugal to have survived relatively intact since the Reconquista times, scientists retrieved a peculiar slow-growing microcolonial black fungus.

What João Trovão of the University of Coimbra (Portugal) and his colleagues were looking at turned out to be a species of a whole new family (Aeminiaceae) in the order of the sooty mould fungi. The new species, its new genus and the novel family are described in the open-access journal MycoKeys.

This is a colony of the newly described black fungus species Aeminium ludgeri. Photo by João Trovão.

To define the new group of fungi, the researchers first scraped off samples from a deteriorated limestone artwork in the “Santa Maria” chapel and then conducted an extensive and integrative analysis, based on morphological, physiological, ecological characters and DNA sequences.

As for the origin of the previously unknown fungus, the scientists hypothesise that the species had ‘arrived’ at the Old Cathedral of Coimbra with the limestone used during its construction. Coming from the unique nearby areas of Ançã and Portunhos, such limestone has been used on several of the “Our Ladies of the O” statues, as well as in the portal of the Royal Hospital in Santiago de Compostela (Spain). Currently, these fungi are considered endemic to the limestone quarries in the Iberian Peninsula.

“Regarding stone monuments exposed to the environment, microcolonial black fungi are considered one of the main culprits for the phenomenon of stone biodeterioration, being responsible for severe aesthetic, biochemical and biophysical alterations,” comment the scientists.

“It is, therefore, crucial to gather deeper knowledge regarding their biodiversity and their biological, ecological and physiological unique characteristics, in order to span our knowledge regarding these fungi and, at the same time, allow the development and improvement of tools to protect stone monuments from their deteriorative effects.”

###

Original source:

Trovão J, Tiago I, Soares F, Paiva DS, Mesquita N, Coelho C, Catarino L, Gil F, Portugal A (2019) Description of Aeminiaceae fam. nov., Aeminium gen. nov. and Aeminium ludgeri sp. nov. (Capnodiales), isolated from a biodeteriorated art-piece in the Old Cathedral of Coimbra, Portugal. MycoKeys 45: 57-73. https://doi.org/10.3897/mycokeys.45.31799

New fungus found to cause cankers and declines in pistachio trees in Sicily, Italy

Starting in the spring of 2010, farmers from Sicily – the major pistachio production area of Italy – have been reporting a previously unknown disease on the trees. Characterised by cankers and declines, it sometimes leads to the collapse of the entire plant.

When the research team led by Salvatore Vitale, Centro di Ricerca Difesa e Certificazione, Italy, studied plants from a total of 15 pistachio orchards in Catania, Agrigento and Caltanissetta provinces, they identified cankers associated with vascular necrosis and tree decline on twigs, branches and stems, alongside abundant gummosis. There were also localised, sunken lesions with several central cracks. These lesions would deepen into the woody tissue, where discolouration and necrotic tissue were also present.

Additionally, the scientists conducted a series of pathogenicity tests on 5-year-old potted pistachio plants (Pistacia vera), which successfully reproduced the field observations. As a result, a previously unknown pathogenic fungus, which colonises the woody plant tissue, has been isolated.

Timelapse of the symptoms reproduced in a potted plant.

The aetiology of the disease and the description of the new species, named Liberomyces pistaciae, are published in the open access journal MycoKeys. Despite cankers and subsequent decline of pistachio trees having been observed in Sicily for several years, the paper is the first work to successfully determine the causal agent.

“On the basis of the high disease incidence and the frequency of this species observed in several orchards in the last years, we believe that L. pistaciae represents amenace to pistachio production in Sicily,” say the researchers.

Symptoms caused by the newly described pathogenic fungus observed in the field.

Out of the 15 surveyed orchards, the scientists detected the presence of the fungus in ten of them. Most of the observations occurred in the winter period and during late spring, but the authors found the pathogen in asymptomatic trees as well, which suggests that the fungus has a dormant growth phase.

When already symptomatic, the plants begin to exudate gum. Often, the bark on their trunks and/or branches would scale, appearing as if cracking and peeling. The initial pale circular areas present in the bark turn dark and sunken with time. Later, the infected patches were seen to expand in all directions, yet faster along the main axis of the stems, branches and twigs. When the scientists examined beneath the bark, they saw discoloured and necrotic tissues. Once the trunk of the tree is encircled by a canker, they report, the whole plant collapses.

Other symptoms include canopy decline as well as wilting and dying inflorescences and shoots growing from infected branches or twigs.

The newly described fungus is characterised with slowly growing colonies. With time, they turn from white to pale to dark brown with a whitish slightly lobed margin.

The researchers warn that essential hazard for the further spread and promotion of the infection is the use and distribution of infected propagation material taken from nurseries and mechanical injuries or pruning wounds.

Further research and studies are currently in progress aiming to extend the survey to other areas in order to eventually formulate effective disease management strategies.

Symptoms caused by the newly described pathogenic fungus observed in the field.

###

Original source:

Vitale S, Aiello D, Guarnaccia V, Luongo L, Galli M, Crous PW, Polizzi G, Belisario A, Voglmayr H (2018) Liberomyces pistaciae sp. nov., the causal agent of pistachio cankers and decline in Italy. MycoKeys 40: 29-51. https://doi.org/10.3897/mycokeys.40.28636

Underwater mushrooms: Curious lake fungi under every turned over stone

While fungi are well known for being essential in cycling carbon and nutrients, there are only about 100,000 described species in contrast to the 1.5 to 3 millions, assumed to exist on Earth. Of these, barely 3000 fungi belong to aquatic habitats. In fact, freshwater fungi have been researched so little, it is only now that an international research team provide the first lake-wide fungal diversity estimate in the open access journal MycoKeys.

Over the spring and the early summer of 2010, a large team of scientists, led by Dr Christian Wurzbacher and Dr Norman Warthmann, affiliated with the Leibniz-Institute of Freshwater Ecology and Inland Fisheries and the Berlin Center for Genomics in Biodiversity Research, Germany (currently at University of Gothenburg, Sweden, and the Australian National University, Australia, respectively), collected a total of 216 samples from 54 locations, encompassing eight different habitats within Lake Stechlin in North-East Germany.image-1

Having recovered samples on three occasions over the course of the study, their aim was to test how habitat specificity affects the fungal community and whether fungal groups would reflect the availability of particulate organic matter as substrate. Unlike previous studies of aquatic fungi that compared water samples among different lakes or seasons, theirs would compare the diversity among habitats within a single lake. This included the study of fungi living in the water and the sediments, as well as fungi living on the surfaces of plants and other animals.

As a result, the scientists concluded that every type of habitat, i.e. sediments, biofilms, and submerged macrophytes (large aquatic plants), has a specific fungal community that varies more than initially expected. Of these, lake biofilms, representing a group of microorganisms, whose cells stick to each other, and cling together to a surface, turned out to be the hotspots for aquatic fungi.

“Our study provides the first estimate of lake-wide fungal diversity and highlights the important contribution of habitat heterogeneity to overall diversity and community composition,” the scientists summarise. “Habitat diversity should be considered in any sampling strategy aiming to assess the fungal diversity of a water body.”

###

Original source:

Wurzbacher C, Warthmann N, Bourne EC, Attermeyer K, Allgaier M, Powell JR, Detering H, Mbedi S, Grossart H-P, Monaghan MT (2016) High habitat-specificity in fungal communities in oligo-mesotrophic, temperate Lake Stechlin (North-East Germany). MycoKeys 16: 17-44. https://doi.org/10.3897/mycokeys.16.9646

Remarkably diverse flora in Utah, USA, trains scientists for future missions on Mars

Future Martian explorers might not need to leave the Earth to prepare themselves for life on the Red Planet. The Mars Society have built an analogue research site in Utah, USA, which simulates the conditions on our neighbouring planet.

Practicing the methods needed to collect biological samples while wearing spacesuits, a team of Canadian scientists have studied the diverse local flora. Along with the lessons that one day will serve the first to conquer Mars, the researchers present an annotated checklist of the fungi, algae, cyanobacteria, lichens, and vascular plants from the station in their publication in the open-access journal Biodiversity Data Journal.

oo_56706Located in the desert approximately 9 km outside of Hanksville, Utah, and about 10 km away from the Burpee Dinosaur Quarry, a recently described bone bed from the Jurassic Morrison Formation, the Mars Desert Research Station (MDRS) was constructed in 2002. Since then, it has been continuously visited by a wide range of researchers, including astrobiologists, soil scientists, journalists, engineers, and geologists.

Astrobiology, the study of the evolution and distribution of life throughout the universe, including the Earth, is a field increasingly represented at the MDRS. There, astrobiologists can take advantage of the extreme environment surrounding the station and seek life as if they were on Mars. To simulate the extraterrestrial conditions, the crew members even wear specially designed spacesuits so that they can practice standard field work activities with restricted vision and movement.

In their present research, the authors have identified and recorded 38 vascular plant species from 14 families, 13 lichen species from seven families, 6 algae taxa including both chlorophytes and cyanobacteria, and one fungal genus from the station and surrounding area. Living in such extreme environments, organisms such as fungi, lichens, algae, and cyanobacteria are of particular interest to astrobiologists as model systems in the search for life on Mars.

However, the authors note that there is still field work to be executed at the site, especially during the spring and the summer so that the complete local diversity of the area can be captured.Martian flora 2

“While our present checklist is not an exhaustive inventory of the MDRS site,” they explain, “it can serve as a first-line reference for identifying vascular plants and lichens at the MDRS, and serves as a starting point for future floristic and ecological work at the station.”

###

Original source:

Sokoloff P, Hamilton P, Saarela J (2016) The “Martian” flora: new collections of vascular plants, lichens, fungi, algae, and cyanobacteria from the Mars Desert Research Station, Utah.Biodiversity Data Journal 4: e8176. doi: 10.3897/BDJ.4.e8176