Archive for the ‘Fungi’ Category

FEBRUARY 22, 2023

Iron treatment boosts rice immune system, shows study

by Center for Research in Agricultural Genomics (CRAG)

Iron boosts rice immune system
Rice plant leaves which have been treated or not with iron (5 days) and infected with the fungus M. oryzae. Credit: CRAG

Rice (Oryza sativa L) is the world’s most widely used cereal for human consumption and the second most produced in the world after maize. However, rice production is seriously threatened by rice blast, a fungal disease that has been reported in more than 80 countries on all continents, including the growing areas of almost all rice-producing regions in Spain (Andalusia, Extremadura, Catalonia, Valencia, etc.).

A study recently published in the journal Rice and led by Blanca San Segundo, CSIC researcher at CRAG, has revealed that exposing rice plants to moderately high levels of iron increases resistance to infection by the pathogenic fungus Magnaporthe oryzae, the agent causing rice blast, the most common disease in this crop and responsible for large production losses worldwide.

Iron is an essential nutrient for plant growth and development. Although it is an abundant element in most agricultural soils, its availability to crops might be low. Depending on the soil characteristics, iron is found in its insoluble or soluble form, and therefore the plant can absorb it more or less effectively. In addition, both a deficiency and an excess of iron can become toxic to the plant. Thus, the precise control of the amount of iron as well as its bioavailability turn out to be crucial for the correct growth and productivity of the crops.

Using RNA sequencing methods, which enables the analysis of expression levels of different genes, the research team has detected the activation of several genes related to plant defenses when rice has been treated with iron for a short period of time. In addition, the presence of iron increases the expression of genes related to the generation of phytoalexins, molecules with antifungal activity which are able to inhibit the growth of Magnaporthe oryzae. Thus, it has been possible to demonstrate that a moderate treatment with iron activates the innate immune system of rice.

This work reveals that, under infection conditions, in the leaves of plants treated with iron, an accumulation of both reactive oxygen species (ROS) and iron is observed in specific and very localized regions of the infected leaf, which correspond to the pathogen entry points. This triggers a process of programmed cell death in the plant cells, known as ferroptosis, which limits the progression of the fungus in the infected tissue and therefore the infection is controlled by the plant itself.

“The cell suicide response or ferroptosis has been described in rice varieties resistant to infection by M. oryzae (incompatible interactions). However, it is the first time that this response has been observed in rice plants that are susceptible to infection by this fungus as a result of iron treatment. Iron has a function that enhances the immune response in the rice plant,” says Blanca San Segundo, the leading researcher of the study.

Previous studies by the same group already pointed out that nutrients could play a key role in the resistance or susceptibility to infection by this fungus. The same research team published in 2020 that excess of phosphate, as a consequence of the excessive use of phosphate fertilizers, has the opposite effect since it makes rice more susceptible to infection by the same fungus.

Understanding the relationship between the supply of nutrients (macronutrients and micronutrients) and the defense response of the plant against pathogens can be very useful when designing new protection strategies against blast disease and hence minimize the associated economic losses. In addition, this knowledge will contribute to establish more sustainable practices for growing rice by reducing the use of agrochemicals (fertilizers and pesticides).

More information: Ferran Sánchez-Sanuy et al, Iron Induces Resistance Against the Rice Blast Fungus Magnaporthe oryzae Through Potentiation of Immune Responses, Rice (2022). DOI: 10.1186/s12284-022-00609-w

Provided by Center for Research in Agricultural Genomics (CRAG)

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Rice blast fungus study sheds new light on virulence mechanisms of plant pathogenic fungi

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Plantain crop hit by fungal disease due to unusual mist

The plantations initially sustain black leaf streak disease that spreads across the tree and gradually the leaves would wilt.

A fungus infested plantain tree in Thanjavur on Wednesday

A fungus infested plantain tree in Thanjavur on Wednesday File

Dt Next Bureau

Published on : 

8 Feb, 2023, 6:19 pm

TIRUCHY: The untimely rains and unusual mist formation resulted in spread of fungal disease in plantain crop. Banana plantations on several acres were affected across the Delta due to the fungal infestation.

According to farmers, banana have widely been cultivated across the region on par with paddy. However, recently, the region has witnessed an unexpected mist condition leading to fungal disease. The plantations initially sustain black leaf streak disease that spreads across the tree and gradually the leaves would wilt.

Though agriculture officials had advised to use a few anti-fungal solutions to prevent the disease, farmers claimed that several trees in the region had sustained the disease in an advance level and they fear that total damage could be the result. So, they appealed to the government to conduct an assessment and provide some relief to the farmers.

“Due to this disease, against the actual 15 leaves in grownup trees, only six are available and other leaves wither away. This results in poor yield and in some trees, the bunches would get destroyed leading to a heavy loss to the farmers who undertake plantain cultivation,” said Mathiazhagan, Thanjavur district president of Banana Farmers Association.

He said that, despite the fungal infection being quite common in banana crops, the unusual mist had aggravated the infection resulting into a total loss of the trees. He also said that the farmers have passed on the information to the Banana Research Centre for a study and are waiting for a remedy from them.

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View as a webpage ARS News Service ARS News Sorghum stalks and some products produced from sorghum grain.

ARS and Purdue University scientists identified a gene that could help sorghum withstand the fungus that causes anthracnose disease. Strengthening Sorghum Against a Worldwide Fungal Threat For media inquiries contact: Jan Suszkiw, (202) 734-1176
February 2, 2023 A gene discovered by a team of Agricultural Research Service (ARS) and Purdue University scientists could help fortify the defenses of sorghum to anthracnose, a disease of the cereal grain crop that can inflict yield losses of up to 50 percent. The discovery, to be reported in an upcoming issue of The Plant Journal, opens the door to breeding disease-resistant sorghum cultivars that are less reliant on fungicides to protect them, reducing growers’ production costs and safeguarding grain yields and quality, among other benefits. Sorghum is the fifth-most widely grown cereal grain crop worldwide, providing consumers not only with a source of food containing 12 essential nutrients, but also forage for livestock and material for bio-based energy. However, unchecked with fungicides or other measures, anthracnose will attack all parts of a susceptible cultivar, often forming reddish lesions on leaves and the stem as well as causing damage to the plant’s panicles and grain heads. Genetic-based disease resistance is the most effective and sustainable approach to combating anthracnose in sorghum. However, how this resistance actually works in the plant is poorly understood, according to Matthew Helm, a research molecular biologist at ARS’s Crop Production and Pest Control Research Unit in West Lafayette, Indiana. That knowledge gap is worrisome because of the genetic variability among different races (or types) of the anthracnose fungus and their potential to overcome a cultivar’s resistance genes over time. Additionally, anthracnose resistance can be temperature-dependent, potentially leaving a sorghum crop vulnerable to infection if temperatures soar above a certain threshold. Fortunately, Helm and a team of Purdue University scientists led by Demeke Mewa have begun to close this gap. They identified a disease-resistance gene that orchestrates a series of defense responses to early infection by the anthracnose fungus, preventing its spread to the rest of the plant and grain heads. Additionally, sorghum plants carrying the resistance gene, known as “ANTHRACNOSE RESISTANCE GENE 2” (ARG2), successfully withstood the fungus even when greenhouse temperatures were increased to 100 degrees Fahrenheit (38 degrees Celsius). This temperature stability could be a potential boon for sorghum production regions of the world where growing season temperatures can reach those levels.  The team also determined that ARG2 helps make (“encodes for”) a protein that is concentrated in the plasma membrane of resistant sorghum cells. There, it acts as a kind of intruder alert that’s triggered by certain proteins used by the anthracnose fungus to infect the plant. “These results significantly advance our understanding of how sorghum detects fungal pathogens and opens the door for engineering new disease resistances against plant pathogens of cereal grains,” the team writes in an abstract summarizing their findings in The Plant Journal paper. ARG2 and its protein don’t protect sorghum from all races of anthracnose. However, combining ARG2 with other similar genes could help broaden that protection—either through conventional plant breeding methods or biotechnological ones. With ARG2’s discovery, scientists now have a key to unlocking a fuller understanding of how the mechanisms of anthracnose resistance work and making the best use of them as a disease defense that growers worldwide can count on. In addition to Mewa and Helm, the The Plant Journal paper’s other authors are Sanghun Lee, Chao-Jan Liao, Augusto Souza, Adedayo Adeyanju, Damon Lisch and Tesfaye Mengiste—all of Purdue University. The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in U.S. agricultural research results in $20 of economic impact. Interested in reading more about ARS research? Visit our news archive U.S. DEPARTMENT OF AGRICULTURE
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JANUARY 12, 2023

Review highlights a century of science in tackling emerging fungal diseases in response to climate change


Review highlights a century of science in tackling emerging fungal diseases in response to climate change
Dr David Smith examines CABI’s living culture collection of over 30,000 strains of fungi and bacteria including 5,000 plant pathogens and other microorganisms. Credit: CABI

A new CABI-led review published in the journal Microbiology Australia highlights how CABI has spent over 100 years identifying and combatting emerging fungal diseases of plants in response to the impacts of climate change.

Dr. David Smith, Emeritus Fellow and former Director, Biological Resources at CABI, led a team of scientists who focused on how climate change is influencing disease occurrence and how CABI’s work and resources can help in the battle to help reduce them.

Ultimately, the researchers highlight how CABI and its 49 Member Countries are working collaboratively with a global network of partners to manage emerging and spreading diseases which can affect livelihoods and impact upon food security.

This includes diseases such as Maize Lethal Necrosis Disease (MLND) which has been negatively affecting maize crops and their seeds in eastern and central Africa. Part of CABI’s work to help mitigate this included a project that sought to enhance the knowledge base on MLND viruses and the epidemiology of the disease in the affected countries.

A key component of CABI’s work in the field is its living culture collection. This was born from the establishment of the Imperial Bureau of Mycology in 1920 and laid the foundation of CABI’s expertise in mycology which continues to this day.

Currently there are over 30,000 strains of fungi and bacteria—including 5,000 plant pathogens and other microorganisms—in the collection of which 90% are unique to CABI. It represents one of the world’s largest genetic resource collections and holds the UK’s National Collection of Fungus Cultures.

Another aspect of CABI’s work is its Diagnostic and Advisory Service (DAS) which provides diagnostic advice on pests and diseases on crops from around the world. An example of this was the confirmation of the invasive apple snail (Pomacea canaliculate)—which threatens Kenya’s rice crops—using DNA analysis.

In addition to sequencing, techniques such as MALDI-TOF (matrix-assisted laser desorption ionization—time of flight analysis) are used are used to identify and characterize disease causing microorganisms.

Other recent new country reports of pests and diseases confirmed by the DAS laboratory include Moniliophthora roreri causing frosty pod rot on cocoa in Jamaica and the fall armyworm (Spodoptera frugiperda) which affects more than 100 plant species and is found in Africa and Asia.

Dr. Smith said, “An understanding of microbes and microbial communities is essential for improving crop yields and facilitating interventions, such as biocontrol of pests, diseases, and invasive species.

“In parallel to the scientific work, CABI information resources are supporting the science and fieldwork to increase the reach, application, and understanding of the science worldwide.”

“In carrying out its work, CABI has seen an impact on emerging disease due to climate change and has implemented programs to help farmers adapt to its impact.”

These programs include the global PlantwisePlus program which works closely with national agricultural advisory services to establish a global network of plant clinics, run by trained ‘plant doctors’.

Rural plant clinics, staffed by agricultural advisors trained through PlantwisePlus, receive diseased samples and provide a timely diagnosis and appropriate remedial advice.

The program has been introduced to 34 countries in Africa, Asia and the Americas, presented over 5,000 plant clinics, trained over 13, 200 plant doctors and reached over 54 million smallholder farmers.

Recommendations to farmers have resulted in halving the use of restricted chemicals, increasing yields by more than 20% and over 1.5 million farmers have improved food security.

Another program is the Pest Risk Information Service (PRISE) which, in sub-Saharan Africa, used earth observation environmental data and models on pest life cycles to create early-warning alerts and advice to farmers on the timely application of pest control products.

It has delivered pest alerts in Kenya, Ghana, Zambia and Malawi to over 1.8 million farmers since it began in 2017. SMS information was sent to 6,000 farmers in Kenya, for example, on the fall armyworm which resulted in 60% of the farmers reporting a change in their farming practices as a result.

Dr. Smith added, “It is clear that climate change exacerbates problems and broadens the scope and range of plant pests and invasive species by enabling organisms to grow in environments from which they have normally been excluded.”

“Predictive models and early warning systems are needed if we are to combat such problems, for which CABI’s information resources and dissemination systems can play a critical role.”

A CABI-led review in the Journal of Economic Entomology has already highlighted several management options for the fall armyworm after recent climatic models reveal that the pest is likely to itself in the southern parts of Europe including southern Spain, Italy, Portugal or Greece.

More information: David Smith et al, CABI’s 100 years in identifying and combating emerging fungal diseases in response to climate change, Microbiology Australia (2022). DOI: 10.1071/MA22054

Dirk Babendreier et al, Potential Management Options for the Invasive Moth Spodoptera frugiperda in Europe, Journal of Economic Entomology (2022). DOI: 10.1093/jee/toac089

Journal information: Journal of Economic Entomology 

Provided by CABI

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Sunday, 08 January 2023 09:37:18


Grahame Jackson posted a new submission ‘Aussie science tackling rusty plant threat’


Aussie science tackling rusty plant threat


When eucalypt-destroying myrtle rust was detected on a cut flower farm and in two nurseries north of Sydney 12 years ago, a major containment operation was launched.

Millions of dollars were spent but to no avail. Within months, the invasive fungus, identified by its bright yellow spots, had swept up the coast and been discovered as far north as Cairns.

It has since spread across the Australian landscape and now flourishes in bushland reserves, backyards, commercial operations, nature strips and park lands alike.

With the exception of South Australia, it’s infiltrated every state including Tasmania, as well as the Tiwi Islands in the Northern Territory.

Authorities agree myrtle rust is now endemic and cannot be eradicated.  

In South America, from where it originated, it’s relatively harmless. Not so locally, given that almost 80 per cent of Australian native trees belong to Austropuccinia psidii’s primary victim, the myrtaceae family.

Among 2000 Australian plants in total, the bottle brush, lemon myrtle, tea tree, lilly pilly, blackbutt and broad-leaved paperbark tree melaleuca quinquenervia are among its most vulnerable members.   

According to the Invasive Species Council, myrtle rust could eventually universally “alter the composition and function of forest, woodland, heath and wetland ecosystems”.

It says the incursion “is about as bad as it can get for biosecurity in Australia”.

Federal Environment Minister Tanya Plibersek agrees a co-ordinated response is needed.

Read on: https://www.aap.com.au/news/aussie-science-tackling-rusty-plant-threat/

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  Grahame Jackson

 Sydney NSW, Australia

 For your information

 8 days ago




ProMED-mail is a program of the
Source: Australian Broadcasting Corporation (ABC) News [summ. Mod.DHA, edited]

Up to 60 percent of the dried vine fruit in the Sunraysia region (southwestern New South Wales/northwestern Victoria) could be lost to the worst downy mildew outbreak in decades, triggered by recent rain. About 9000 tonnes of crops could be lost to the infection. The region produces 98 percent of the country’s dried vine fruit exports.

Dried Fruits Australia said the vines look quite good, but there are no bunches of grapes, they have dried up and fallen off. Some growers may not even harvest their grapes this 2022 season. Wine grapes have also been devastated by downy mildew. One grower said he has lost 70 percent of his wine crop

[Byline: Peter Sanders, Kellie Hollingworth]

Communicated by:

[Downy mildew on grapevine is caused by the fungus-like organism (oomycete) _Plasmopara viticola_. It causes lesions on leaves which later become covered with white downy growth and turn necrotic. It can also affect flowers and fruits. Disease development is favoured by temperatures of 15 to 20 deg C (59 to 68 deg F) and moist conditions. In years with warm, extended wet periods during bloom, fruit clusters may be partially or totally destroyed. The disease can cause severe crop losses and occurs irregularly in most grape growing regions worldwide.

Spores are spread within a crop mainly by splashing rain, wind, or mechanical means. The pathogen survives between crops on infected plant debris as oospores, which are formed inside the host tissues. It is an obligate parasite and cannot be cultured in vitro. Disease management relies mainly on preventative fungicide applications according to forecasting services. Systemic fungicides are also available. All commercial grape cultivars are susceptible.

Downy mildews include many species of oomycetes in several genera which cause similar symptoms in a range of hosts, including many crops. Individual species usually have a narrow host range affecting only one or a few different hosts.

Australia (with states):
https://www.nationsonline.org/maps/australia-political-map.jpg and
Sunraysia region:

Downy mildew on grapevine leaves & bunches:
https://i.pinimg.com/originals/b6/9d/aa/b69daafeaa444558d055ac67d538f046.png (upper & lower leaf surface),
https://www.agric.wa.gov.au/sites/gateway/files/downy%20in%20bunches%20(20).JPG, and via
http://grapepathology.blogspot.com/2009/06/downy-mildew-gallery.html (photo gallery)

Information on downy mildew of grapevine (with pictures):
https://www.agric.wa.gov.au/table-grapes/downy-mildew-grapevines, and
_P. viticola_ taxonomy and synonyms:
– Mod.DHA]




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Monday, 26 December 2022 09:19:56

Grahame Jackson posted a new submission ‘Cross-kingdom synthetic microbiota supports tomato suppression of Fusarium wilt disease’



Cross-kingdom synthetic microbiota supports tomato suppression of Fusarium wilt disease


Nature Communications volume 13, Article number: 7890 (2022) 

The role of rhizosphere microbiota in the resistance of tomato plant against soil-borne Fusarium wilt disease (FWD) remains unclear. Here, we showed that the FWD incidence was significantly negatively correlated with the diversity of both rhizosphere bacterial and fungal communities. Using the microbiological culturomic approach, we selected 205 unique strains to construct different synthetic communities (SynComs), which were inoculated into germ-free tomato seedlings, and their roles in suppressing FWD were monitored using omics approach. Cross-kingdom (fungi and bacteria) SynComs were most effective in suppressing FWD than those of Fungal or Bacterial SynComs alone. This effect was underpinned by a combination of molecular mechanisms related to plant immunity and microbial interactions contributed by the bacterial and fungal communities. This study provides new insight into the dynamics of microbiota in pathogen suppression and host immunity interactions. Also, the formulation and manipulation of SynComs for functional complementation constitute a beneficial strategy in controlling soil-borne disease.

Read on: https://www.nature.com/articles/s41467-022-35452-6

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Understanding the Mystifying Function That Fungi Play in Ecosystems

TOPICS:Dartmouth CollegeEcologyEvolutionFungi


Shaggy Scalycap

Fruiting bodies of shaggy scalycap (Pholiota sp.) on a log just off the Appalachian Trail in Hanover, New Hampshire. Credit: Bala Chaudhary

New scientific review analyzes what we know about how fungi disperse.

When you say “fungi,” most people think of mushrooms, the fleshy fruiting bodies above the ground or food source, but most fungi do not actually produce mushrooms. Furthermore, of the estimated 3 to 13 million fungal species on Earth, many are microscopic in size, and therefore invisible to the naked eye.


Fungi live in a wide range of environments including in soils, inside the tissues of leaves in rainforests, and in deep oceans. Understanding how fungi move across a range of spatial scales is important to understanding ecosystems and has significant implications for agriculture and human health, according to a new review published in the journal Annual Review of Ecology, Evolution, and Systematics.

Fungi are frequently associated with death and decay, such as mold that grows on old food, or mushrooms that decompose leaves on the forest floor. “We typically think of fungi as decomposers, but they are cryptic and do many different things,” says lead author Bala Chaudhary, an associate professor of environmental studies at Dartmouth. “Fungi can also function as nutrient cyclers, pathogens, and mutualists that live in a beneficial association with plants and other organisms.”

Fungi can also be human pathogens. For example, Coccidiodes is another soil-borne fungus that releases spores into the air as a result of land disturbance and soil degradation. When the spores of this fungus are inhaled, Coccidiodes can cause a serious respiratory disease called Valley fever, also known as coccidioidomycosis. Soil ecology, climate justice, and environmental health are three fields that interconnect and might benefit from a better knowledge of fungal dispersal.


“Experts working in agriculture, public health, and many other fields are interested in understanding fungal dispersal, as this information can be used to predict things like future crop pandemics and outbreaks of human disease,” says Chaudhary, who is an ecologist. “Furthermore, studying how fungi disperse is central to understanding fungal biodiversity and where species are distributed on Earth.”

Chaudhary’s co-authored analysis on how fungi disperse is the result of a collaboration with senior author Matthias Rillig, a professor of plant ecology at the Institute of Biology at Freie Universität Berlin, and members of his lab, during her sabbatical in 2019-20.

To synthesize existing information on fungal dispersal and highlight emerging research in this area, the team used a research-weaving approach that combines reviewing journal articles with analyzing trends in publishing, also known as “bibliometrics.” The team examined over 4,500 documents from nearly 1,200 sources from 1951 to 2021. Most of the articles pertained to fungal dispersal research in the United States, the United Kingdom, and China.

The researchers found that scientific literature on fungal dispersal has focused on three topical areas: fungal disease, including climate change, which was the most prominent theme represented; fungal diversity, communities, and mycorrhizal fungi, including soils and forests; and the evolution of fungi, including molecular methods.

As part of their analysis, the researchers pose theoretical relationships between the relative importance of vectors of dispersal and spatial scale and vectors of dispersal. They identified four scales of fungal movement from microscopic to landscape scales.

Tiny root-like structures of fungi at the mycelial level move through the soil on the smallest scale. Invertebrate animals, including micro/macroarthropods such as ants, and earthworms can transport fungi through their castings and nests, and small mammals and birds who may transport fungi via their feet, feathers, and digestive tracks serve as vectors for moving fungi at larger scales. Abiotic vectors, such as water and wind, are responsible for fungal movement at the largest scale across the landscape and continents. Rivers transport sediment containing fungi propagules across continents, ocean currents and tides, and precipitation, as well as humans, all play a role in the global transit of fungi.

“With climate change, environments are getting dryer in some regions and wetter in others, factors that can change where fungi reside,” says Chaudhary. “Soil disturbance from agriculture, land development, and other human activities can also release soil fungi into the air.”

“Climate change, coupled with anthropogenic land use, can really impact the way that fungi move. The relative importance of movement vectors changes across spatial scale, but there’s very little data to support these relationships,” she says.

“More data is needed to understand the biodiversity of fungi and the many factors affecting their movement in our ecosystems.”

Reference: “Fungal Dispersal Across Spatial Scales” by V. Bala Chaudhary, Carlos A. Aguilar-Trigueros, India Mansour and Matthias C. Rillig, 25 July 2022, Annual Review of Ecology Evolution and Systematics.
DOI: 10.1146/annurev-ecolsys-012622-021604

Carlos Aguilar-Trigueros and India Mansour at the Institute of Biology at Freie Universität Berlin also contributed to the study.

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Open Letter on the crucial role of fungi in preserving and enhancing biodiversity

Latest news

Published on14.12.2022



When we think of forests we usually think of trees, plants and animals. But forests could not exist without fungi, which lie at the base of the biodiversity webs that support much of life on Earth.

Most fungi live as branching, fusing networks of tubular cells known as mycelium which can make up between a third and a half of the living mass of soils. Globally, the total length of fungal mycelium in the top 10cm of soil is more than 450 quadrillion km: about half the width of our galaxy. These networks comprise an ancient life-support system that easily qualifies as one of the wonders of the living world. Despite that, fungi represent a meagre 0.2% of our global conservation priorities.  

Fungi are largely invisible ecosystem engineers that have shaped life on Earth for more than a billion years. In fact, around 500 million years ago, fungi facilitated the movement of aquatic plants onto land, fungal mycelium serving as plant root systems for tens of millions of years until plants could evolve their own. This association transformed the planet and its atmosphere – the evolution of plant-fungal partnerships coincided with a 90% reduction in the level of atmospheric carbon dioxide. Today, most plants depend on mycorrhizal fungi – from the Greek words for fungus (mykes) and root (rhiza) – which weave themselves through roots, provide plants with crucial nutrients and defend them from disease.

Put simply, fungal networks embody the most basic principle of ecology: that symbiosis is fundamental to life on earth. Plants supply carbon to their fungal partners in exchange for nutrients like nitrogen and phosphorus – much of the phosphorus that makes up the DNA in your own body will have passed through a mycorrhizal fungus. In their exchange, plants and fungi engage in sophisticated trading strategies. The influence of these quadrillions of microscopic trading decisions spills out over whole continents. Globally, at least 5 billion tons of carbon dioxide are allocated from plants to mycorrhizal networks each year.

A call to action

A paradigmatic but often forgotten example of the keystone role of fungi is in the world’s forests, which are among the most important biological systems on our planet. They are our largest terrestrial carbon sink and the main terrestrial source of precipitation and oxygen. They house much of the planet’s biodiversity, serving as irreplaceable libraries of different ways to rise to the challenge of living.

However, current biodiversity, climate change, and sustainable food strategies, including forest restoration efforts overlook fungi and focus overwhelmingly on plants (flora) and animals (fauna). We urgently need to add a third “F” – funga – to create holistic conservation strategies that simultaneously address the triple planetary challenges of climate change, biodiversity loss and food security.  

Fungi must be incorporated into law-making and decision-making in international environmental treaties and frameworks, as well as national agricultural and environmental laws and policies, and local conservation and environmental initiatives. We invite the leaders meeting in COP 15 to start this process by adding fungi to the Post-2020 global biodiversity framework. Fungi have long sustained and enriched life on our planet. It’s time they receive the attention they deserve.

This open letter was written by:

Marc Palahí, Director European Forest Institute
Toby Kiers, Director Society for the Protection of Underground Networks
Merlin Sheldrake, author of Entangled Life
Giuliana Furci – Executive director, Fungi Foundation & co-chair IUCN SSC Fungal Conservation Committee
Robert Nasi, Chief Executive Officer, CIFOR-ICRAF
César Rodríguez-Garavito, Professor of Clinical Law and Director, Earth Rights Advocacy Clinic, New York University School of Law

Photo: Carolina Magnasco/Fungi Foundation


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DECEMBER 20, 2022

Researchers analyze performance of bacterium in combating coffee rust

by Ricardo Muniz, FAPESP

Researchers analyze performance of bacterium in combating coffee rust
The research is part basic science, investigating the bacterium’s resilience in a hostile environment—coffee leaves—and part biotech, seeing whether the bacterium inhibits the development of a pathogen. Credit: Jorge Mondego/IAC

A new study has analyzed the potential of a bacterium for biological control of the fungus Hemileia vastatrix, which causes coffee rust, a major challenge for Brazilian coffee growers. An article on the study is published in the journal BMC Microbiology.

The symptoms of coffee rust are yellow spots like burn marks on the leaves of the plant. The disease impairs photosynthesis, making foliage wither and preventing bean-producing cherries from growing until the tree resembles a skeleton. It is typically controlled by the use of copper-based pesticides, which can have adverse effects on the environment.

“This was a basic science study, in which we set out to understand the behavior of bacteria that inhabit the leaves of coffee trees. First of all, there are several compounds that are harmful to bacteria and can be used to attack them,” said Jorge Maurício Costa Mondego, last author of the article.

“Second, leaves are environments that undergo significant environmental pressures, such as sunlight and rain. We wanted to understand how bacteria that live on coffee leaves can withstand both the compounds produced by the coffee plant and the stresses of rain and sun,” he said.

Besides this basic science front, the study also addressed applied science challenges. The researchers decided to find out whether bacteria that inhabit coffee leaves can combat the fungus that causes coffee rust. The first step consisted of identifying the expressed sequence tags (ESTs) of Coffea arabica and C. canephora produced by the Brazilian Coffee Genome Project (Projeto Genoma EST-Café).

“I was the first author, alongside Ramon Vidal, a professor at UNICAMP, of an article in which we compiled the sequences expressed by C. arabica. It was published in 2011. We weren’t yet thinking in terms of metagenomics, but that’s what we did, more or less accidentally,” Mondego said.

Accidental metagenomics

The researchers found sequences they considered contaminating in the midst of the coffee leaf ESTs. “We took these sequences, fed them into the database, and concluded that they appeared to be from Pseudomonas spp, a genus of bacteria.,” Mondego said. “This stimulated the curiosity of our research group, which was led by Gonçalo Pereira, also a professor at UNICAMP. We asked ourselves, ‘What if we’ve done metagenomics without meaning to? Do these bacteria really live on coffee leaves?'”

At the time, Mondego was already a researcher at IAC. A few years later, he was able to join forces with Leandro Pio de Sousa, first author of the article published in BMC Microbiology. Sousa was a student who had a scientific initiation scholarship and now holds a Ph.D. in genetics and molecular biology from UNICAMP.

“I invited Leandro to work with me on this study, which was designed to see if Pseudomonas really does live on coffee leaves. If so, the previous findings would be confirmed. He agreed immediately,” Mondego said.

They isolated bacteria from the coffee leaves and put them in a culture medium. Under ultraviolet light, it is possible to characterize Pseudomonas, which looks purple and can easily be selected in the medium. “We collected the bacteria, extracted their DNA and sequenced one, which we called MN1F,” he said.

They made several interesting discoveries about MN1F, which has a secretion system that reflects its need to survive in a hostile environment full of fungi and other bacteria. “The secretion system produces antibacterial and antifungal compounds. That suggested it could be used for biological control,” Mondego said. They also detected a number of proteins associated with protection against water stress.

The next step entailed physiological experiments, whereby bacteria were cultured in different media to confirm the researchers’ observations regarding the genome. “The biological experiments proved several inferences correct. We showed that the bacterium does indeed have a considerable capacity to withstand strong osmotic pressure, which can be considered analogous to the effects of drought on coffee leaves,” Mondego explained. “Furthermore, MN1F is capable of degrading phenolic compounds that can be harmful to it. It breaks down these compounds from the plant and converts them into material for its own survival.”

The researchers then conducted a battery of tests to find out if MN1F could be used for biological control, preventing or inhibiting the development of H. vastatrix, the fungus that causes coffee rust. The tests took place under greenhouse and laboratory conditions, including an attempt to inhibit in vitro germination of the fungus. In all of the experiments, the bacterium proved capable of inhibiting the development of spores (reproductive units) and mycelium (the filamentous network containing the fungus’s genetic material).

More information: Leandro Pio de Sousa et al, Functional genomics analysis of a phyllospheric Pseudomonas spp with potential for biological control against coffee rust, BMC Microbiology (2022). DOI: 10.1186/s12866-022-02637-4

Journal information: BMC Microbiology 

Provided by FAPESP 

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Virus Undercuts Fungus’s Attacks on Wheat

USDA Agricultural Research Service sent this bulletin at 11/29/2022 10:05 AM EST

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ServiceFusarium head blight on wheat
A “mycovirus” could help stop the Fusarium head blight fungus from contaminating wheat grains and giving them a ghastly bleached appearance (shown at right).Virus Undercuts Fungus’s Attacks on Wheat
For media inquiries contact: Jan Suszkiw, (202) 734-1176

November 29, 2022 A naturally occurring virus co-discovered by Agricultural Research Service (ARS) and university scientists may offer a way to undermine a costly fungal threat to wheat, barley and other small-grain crops.The fungus, Fusarium graminearum, is the chief culprit behind a disease called Fusarium head blight, or “scab.” Unchecked with fungicides or other measures, scab diminishes the yield and quality of the crops’ grain. Under wet, humid conditions, the scab fungus can release a toxin called deoxynivalenol (a.k.a., “vomitoxin”) that can contaminate the grain, reducing its point-of-sale value or leading to outright rejection depending on end use.Now, however, a team of scientists with the ARS Application Technology Research Unit in Wooster, Ohio, and South Dakota State University in Brookings (SDSU) has discovered a strain of a fungal virus, or “mycovirus,” that disables the scab fungus’s vomitoxin-making machinery.In nature, the mycovirus, a species called Fusarium graminearaum Vg1, infects the scab fungus to replicate and spread. But the new mycovirus strain, dubbed F. graminearum Vg1-SD4, takes such attacks a step further by stopping the scab fungus from making vomitoxin—a fortuitous benefit for wheat plants.Indeed, in laboratory and greenhouse experiments, cultures of the scab fungus that had been infected with the mycovirus strain grew slower than non-infected cultures and produced no vomitoxin in the grain of susceptible potted wheat plants. In contrast, the grain of wheat plants exposed to mycovirus-free cultures of scab contained 18 ppm of vomitoxin, a byproduct of the fungus’s metabolism that can be harmful to livestock and human health.ARS molecular biologist Shin-Yi Lee Marzano and her collaborators discovered the mycovirus strain after sequencing its genomic makeup and noticing slight differences from its “parent” species, FgVg1, which had been maintained in a live culture of the scab fungus and known to science for about a decade.Marzano cautioned that their research—reported in the July 2022 issue of Microorganisms—is still in its early stages. However, with further study, the mycovirus strain could prove useful as a biological control agent that could be formulated and sprayed onto susceptible wheat varieties or other small-grain crops. That, in turn, could potentially offer growers another tool to use in avoiding costly losses to scab and its contamination of grain destined for livestock and human consumption.  Marzano collaborated on the mycovirus strain research with Bimal Paudel and Yang Yen—both with SDSU’s Department of Biology and Microbiology—and Connar Pedersen (formerly SDSU and now ARS).The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in U.S. agricultural research results in $20 of economic impact.Interested in reading more about ARS research? Visit our news archiveU.S. DEPARTMENT OF AGRICULTURE
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