Phytophthora infestans, the water mould that causes late blight in potatoes, consumes and rots the leaves and tubers of the plant.
it would take Phytophthora infestans only a couple of years to defeat it. But now that the sequence is complete,
and elusive lifestyle of this fungus, offering clues that could help a truffle industry that is fraught with unpredictable yields and a counterfeit market.
which visits the fungus in search of a mate but carries off fungal spores instead, spreading them between truffles.
which the fungus trades nutrients with oak-tree roots. The T. melanosporum genome also reveals that the fungus reproduces sexually more often than researchers thought.
Many growers rely on asexual truffle propagation, in which two haploid cells from a single fungus each with one copy of the genome fuse to form the diploid fruiting body (the truffle),
which has two copies. Yet Martin and his team found two different sets of mating genes in the black truffle,
In 2008, Martin and his colleagues reported the genome of Laccaria bicolor, another symbiotic fungus that is dependent on woody plants for nutrients2.
and four times larger than that of many fungi but it contains far fewer protein-coding genes.
Mycologist David Hibbett of Clark University in Worcester, Massachusetts, says that he is amazed to learn that the two species of fungi share any genes involved in symbiosis at all.
Although the sequenced genome opens up the possibility of genetically engineering other fungi to pack the same aromatic punch as the PÃ rigord
Virulent wheat fungus invades South africa: Nature Newstwo new forms of a devastating wheat fungus, known as Ug99 stem rust,
have shown up in South africa, a study has found. The two South african forms are able to overcome the effects of two resistance genes in wheat that normally prevent stem rust from taking hold.
The genes cause plant cells around the infection site to die, stopping the fungus from further infecting the plant.
They are two of the most important genes in wheat because they are selected for in crop-breeding programmes across the world.
The discovery of the new forms marks the first time that the stem rust fungus with virulence against key genetic resistance has moved south of its origins in Uganda
and south Asia vulnerable as the fungus can now migrate using different wind trajectories, says Zacharias Pretorius, a wheat pathologist at the University of the Free state in Bloemfontein, South africa,
Pretorius and his colleagues will present their research in early June at a conference on wheat rust in St petersburg, Russia, organized by the Borlaug Global Rust Initiative,
resistant varieties to ensure crops are protected against the fungus. The reddish-brown, wind-borne fungus was discovered first in Uganda in 1999
and has since spread to five countries, including Kenya, Ethiopia and Iran. It attacks the stems of wheat plants by destroying vascular tissue
The fungus can devastate harvests: for example, farmers in the Narok region of Kenya lost up to 80%of their wheat crop due to Ug99 in 2007.
In total, seven mutant strains of the fungus are known now, including the latest forms, originally identified in South africa in 2007 and 2009.
and less dangerous form of the fungus found in South africa in 2000. The team found that the variant detected in 2007 is likely to have arisen through a single mutation of the more common form,
The fungus and its variants are now able to overcome at least 32 of around 50 resistance genes, according to Ravi Singh, a plant geneticist and pathologist at the Mexico-based International Maize and Wheat Improvement Centre.
An international project that is researching resistance to wheat rust led by Cornell University, is developing new tools to help defeat the pathogen.
the only cereal that is not damaged by the rust, is immune.
News briefing: 20 may 2010: Nature Newspolicy Research Business Business watch People The week ahead News maker Number crunch Policy Oil spill:
or whether there is an equal distribution of numbers between species. The team looked at the bugs, nematodes and fungi that attack the hated Colorado potato beetle (Leptinotarsa decemlineata).
Research Wheat fungus: Two new forms of a devastating wheat fungus known as Ug99 stem rust have arisen in South africa.
Researchers at the University of the Free state in Bloemfontein found that the new variants can overcome the effects of two resistance genes in wheat that normally prevent stem rust from taking hold.
There is concern that winds will help the fungus to migrate further, threatening crops in areas including the Middle east and south Asia.
See go. nature. com/flsdmx for more. Bird blues: As many as 1, 240 bird species are threatened with extinction,
Nature Newsresearchers have traced the key genetic changes that enabled the plant pathogen responsible for the 1845 Irish potato famine (Phytophthora infestans) to jump from wild plant hosts to cultivated potatoes.
husbanding their bacterial'crops'much as some ant species farm fungus. As social amoebae, slime moulds are bizarre creatures that live as individual singled-celled organisms while feeding,
such as fungus-farming ants although compared to the ants, which actively feed, nurture and defend their crops,
or fungus that might pose a threat. And its shop doesn't sell anything that is considered invasive.
Wheat killer A research programme tackling a devastating wheat fungus has been granted US$40 million over five years as part of a partnership between the Bill & Melinda Gates Foundation in Seattle, Washington,
The Durable Rust Resistance in Wheat project, involving more than a dozen institutes and coordinated by Cornell University in Ithaca, New york,
including viruses, bacteria and fungi some novel that, alone or in combination, might push a bee colony into precipitous decline.
At the meeting, Cornman presented data showing that hives affected by CCD have higher levels of microscopic gut fungi called Nosema,
Other people had looked at melanins in fungus near Chernobyl. Eumelanin helps defend fungus, says Ismael Galv ¡
n a biologist at the University of Paris-Sud and a contributor to the new study along with Mousseau and M ¸ller.
of which has potential for use in fighting devastating diseases such as the potato cyst nematode and the potato blight pathogen Phytophthora infestans, famous for causing The irish potato famine of the 1840s.
but the fungus responsible has never wrought such havoc before. The fungus, Exserohilum rostratum, is a plant-eating generalist equipped with a spore-launching mechanism ideal for going airborne,
is not an especially picky eater and, although it prefers grasses, will dine on many items including humans.
The errant fungus has been identified in lab samples from 52 of those affected and was similarly found growing in unopened vials of the steroid alleged to have caused the outbreak, according to the U s. Centers for Disease Control and Prevention.
The fungus, which seems to prefer tropical and subtropical environments, has turned up on a wide variety of plant species,
an emeritus professor in the Department of Plant pathology at the University of Minnesota who retired in 2001 from the U s. Department of agriculture's Cereal Disease Lab (then the Cereal Rust Lab). Early in his career,
but only distantly related, fungi with multicellular dark spores that were causing disease in grains such as corn.
when the plant died the fungus was first in line to feed on its decaying remains. I think it's just a general weak pathogen of plants,
creating a convenient landing pad of dying tissue for the fungus. Most often the fungus shows up on grasses and other monocots plants often distinguished by flower parts in threes and parallel leaf venation such as pineapples, bananas and sugarcane,
but it has also been found on non-monocots such as grapes and muskmelon. It's a fungus that is not, apparently, very picky about its food.
It's just a really common fungus in the environment that mostly lives on dead and dying plant tissue,
Leonard says. There are many such others, and many of them can also occasionally infect animals or people.
The fungus can grow from a single spore to a lawn of freshly spore-crowned fungal filaments on a piece of dried leaf in two days flat faster and more abundantly than any other related species he studied.
This is a fungus very well-adapted to colonizing senescent or dead leaf tissue once conditions are right,
. But if the fungus is primarily tropical and subtropical, what was it doing in a place like New england?
In the summer the fungus can probably find ideal growing conditions in places in the northern U s,
And plentiful lawn clippings provide an ideal place for the fungus to grow. Roberts says the group of fungi pigmented with melanin
(which includes E. rostratum) the same molecule that darkens and protects human skin seem to be generating more human infections for reasons he does not understand.
Although the identity of the fungus surprised him, Roberts was not surprised by its ability to capitalize on its situation once inside a patient.
After the fungus was injected along with the drug into the epidural space the space between the dura mater,
and the inside walls of the vertebrae the fungus's filaments were able to penetrate the dura mater,
thereby shortening the fungus s deadly path into the spinal fluid. Then, in some fatal cases, the fungal filaments began to grow in the brain,
The fungus's confinement to just three lots of the drug also remains unexplained. If the facility's water or air supplies in general were contaminated,
Fungus that controls zombie-ants has own fungal stalkeran article by Scientific American. An unsuspecting worker ant in Brazil's rainforest leaves its nest one morning.
Within days the stem of a fungus sprouts from the dead ant's head. After growing a stalk,
the fungus casts spores to the ground below, where they can be picked up by other passing ants.
zombie-ant fungus even in the scientific literature. But scientists are just learning the intricacies of this interplay between the Ophiocordyceps parasitic fungus
and the Camponotini carpenter ants that it infects. Fossil evidence implies that this zombifying infection might have been happening for at least 48 million years.
Recent research also suggests that different species of the fungus might specialize to infect different groups of ants across the globe.
And close examination of the infected ant corpses has revealed an even newer level of spooky savagery other fungi often parasitize the zombie-ant fungus parasite itself.
We have advanced a great deal in understanding how the fungus controls ant behavior David Hughes, an assistant professor of entomology and biology at The Pennsylvania State university, says.
Deadly infection This clever Ophiocordyceps fungus depends on ants to reproduce and spread, but it has found an abundant host animal.
Evans suggests that a nerve toxin spurred on by the fungus is at least partly to blame
This position appears to be optimal for the fungus's later stage in which it ejects spores onto the soil directly below.)
The zombies'bites are synchronized near noon (possibly cued by clock genes in the fungus) and usually occur in a north-northwestern orientation.
Scientists have found that the fungus also triggers atrophy in its victim's muscles specifically those around its mandibles.
This seemingly small detail is crucial to the fungus's success. Without the death grip,
destroying the launching point for the fungus's spores. By that stage, cells from the fungus have grown even more numerous in the ant's body.
They have proliferated around the ant's brain and between surrounding muscle fibers but have not entered the brain,
Researchers have discovered also that this relatively slow-growing fungus can have its main stem broken off and regrow it later.
The death of an ant outside of its colony and subsequent growth of the fungal stalk might be key adaptations of the fungus,
The fungus has capitalized on ants'social behavior. Sociality can be thought of as evolution's winning lottery ticket
But this zombie fungus is natural selection's tax man. The zombie fungus, however, cannot live without the winning ants'continued success. It appears to be an obligate parasite,
requiring a specific, local species of ant for it to inhabit, grow and propagate its spores.
A specialized but global threat The ants best known for getting zombified by the Ophiocordyceps fungus are tree-dwelling carpenter ants found in Brazil and Thailand,
but the fungus is thought to be distributed broadly in tropical areas around the globe. In fact, the full range of strange behavior observed in Sulawesi
the species of fungus infecting them is not at all the same. Instead of one variable species, there may be tens
Hughes and Simon Elliot (of the Department of Animal Biology at the Federal University of Vicosa in Brazil) described four new species of the Ophiocordyceps fungus that were found in just a small section of rainforest in Brazil
This hint at such vast diversity and specialization also contains broader implications for assumptions about fungus numbers in general.
Ancient scourge The zombifying fungus's vast geographic distribution also hints at the possibility that it has been possessing ants at least
During that time period the region of Germany would have been similar in climate to the areas of Thailand where contemporary zombie-ant fungus has been documented.
A parasite's parasite The zombie-ant fungus is not the end of the parasitizing line
Andersen and her colleagues have found that a different breed of fungi grow over the ant corpse and the emerging fungus stalk.
By covering the original fungus and its stalk, this secondary fungus or hyperparasite effectively prevents the zombie-ant fungus from ejecting its spores.
It looks like they completely sterilize it, Andersen says of the second-level parasite. Even these hyperparasites seem to be specialized for growing on specific parasitizing fungi.
They're not really growing on anything else in the area Andersen says. This makes the hyperparasite another obligate parasite,
which depends on the zombie-ant fungus, which depends, in turn, on the carpenter ant colony. Once you're very successful,
The zombie-ant fungus's doom, of course, is little consolation for the infected ant. But the castration of the ant-killing fungus means that it will not go on to turn other local ants into zombies.
This hobble might, in fact, be one of the reasons the zombie-ant fungus has been so successful over the long term.
As a deadly infection it could severely damage an ant colony. But, if another parasite renders more than half of its mature spores infertile
the actual reproduction rate for each mature zombie-ant fungus organism is a little more than one new mature organism,
In addition to the fungicidal fungi scientists have seen also small bugs laying their eggs in the infected ant corpse,
where their larvae can then eat the growing fungus. These bugs include specialized gall midges (in the Cecidomyiidae family)
It seems their entire nutrition comes from eating the fungus that manipulates ant behavior. are specialized such hyper hyperparasites a freak occurrence?
and most ant cadavers have hyperparasites exploiting the zombie-ant fungus at some stage, Hughes notes.
Learning about zombie-ant funguses is not simply an exercise in outrã Â science. As Hughes notes, discovering more about both the fungus
and the ant behavior and signaling dynamics could add to research about pest control for agriculture.
and the challenges farmers in tropical countries face from insects and fungi that infect their crops,
'a disease caused by the fungus Chalara fraxinea, but this will not stop the pathogen from killing up to 99%of the ash trees in the country,
where the fungus has ravaged ash trees from Poland to France for more than a decade. On the upside, ash trees reproduce
Was it a new species of fungus, or a variant of an old, endemic species of fungus?
Mycologists first attributed ash dieback to Hymenoscyphus albidus, a species endemic to Europe that they thought had developed into a new, more virulent strain.
The fungus Hemileia vastatrix which causes coffee rust, looks set to wipe out half the nation s 2013-14 harvest in the most affected areas.
On 22 Â January, the government signed an emergency bill to tackle the outbreak. The disease has attacked already coffee crops in South and Central america.
But the long stalemate between growers and the fungus behind the devastating disease has broken with the fungus taking the advantage.
Caused by the fungus Hemileia vastatrix, coffee rust generally does not kill plants, but the Institute of Coffee of Costa rica estimates that the latest outbreak may halve the 2013-14 harvest in the worst affected areas of the nation.
and Mexico since the rust arrived in the region more than 40 years ago, says John Vandermeer, an ecologist at the University of Michigan in Ann arbor,
On 22 Â January, Costa rica enacted emergency legislation to speed up the flow of government money towards fighting the fungus.
The fungus first emerged as a significant problem by 1869 in Ceylon now Sri lanka before spreading around the world.
Stuart Mccook, a historian at the University of Guelph in Canada who studies the rust,
says that the wet weather in some areas of Ceylon was ideal for the spread of the fungus,
By 1970, the fungus had been detected in Brazil, and severe outbreaks were seen in Costa rica in 1989
"Coffee rust was considered a solved problem by most of the coffee growers and coffee institutes of the region,
says that rust has been causing ever-greater problems, although in Kenya, varieties resistant to the rust have held it at bay.
Colombia could be the closest to a solution. Marco Aurelio Cristancho, a researcher at Cenicafã, the National Centre for the Investigation of Coffee in Chinchin ¡
The government has supported also work on the genetics of both the fungus and the plant. Research programmes have started in other countries, too.
Fungi and roots store a surprisingly large share of the world's carbonthe largest fraction of carbon held in the soils of northern forests may derive from the living
and the decomposing roots of trees and shrubs and the fungi that live on them. By some estimates, the planet's soils contain more than twice the carbon in the atmosphere.
The difference in carbon-sequestration rates, the researchers report in Science1, can be explained entirely by carbon derived from the roots of trees and shrubs and their symbiotic fungi.
These organisms, dubbed ectomycorrhizal fungi, colonize roots and gain nourishment from the plants while helping their hosts to absorb water and nutrients from the soil.
Whereas about 47%of the soil carbon on the large islands came from roots and ectomycorrhizal fungi
It is unclear why the small islands built up a larger fraction of root-and fungi-derived carbon in the past century,
Symbiotic fungi are a dominant component of a soil s microbial community, she notes in an article accompanying the team s research2."
while that trees divert carbon to their ectomycorrhizal fungi, but having 70%of soil carbon derive from them is much more than we could have expected,
as well as their roots and fungi, causing an ovrall increase in carbon sequestration
Will we kill off today's animals if we revive extinct ones? An article by Scientific American.
they could play a part by making bees more susceptible to the parasitic mite Varroa destructor and the parasitic fungus Nosema apis,
Phytophthora infestans, which causes potato late blight, is an oomycete a type of single-celled organism related to brown algae.
a devastating disease caused by the fungus Venturia inaequalis. In 1999, they finally produced a tasty variety that contained the Vf defence gene,
Among the biggest threats are fungi and oomycetes, similar but distinct groups of microbes, which cause plant diseases.
Several highly virulent strains of fungi have emerged in recent years around the world, and the oomycete Phytophthora infestans remains a persistent problem even 168 years after causing the great Irish potato famine4.
Global movement of crop pests had never been analysed comprehensively. To fill this gap Bebber and his colleagues made use of historical records held by CABI (formerly known as the Centre for Agricultural Bioscience International),
the rate of shift varied significantly for different groups and among individual species. Fungi, beetles, true bugs, mites,
She highlights the worrying finding that fungi and oomycetes are moving particularly quickly, at 7 and 6 km per year respectively.
and their symbiotic fungus Leptographium procerum is key to their personality change in China (J.  Sun et  al.
) Since its arrival,"the fungus has mutated into novel genotypes, says Sun. One of these induces trees to release large amounts of the compound 3-carene a strong attractant to the beetles that is not released in response to the north American fungal variant.
Fungus discovery offers pine-wilt hopethe pine-wood nematode is a major pest in the forests of China.
Sun Jianghua and his colleagues at the Chinese Academy of Sciences Institute of Zoology in Beijing have identified a fungus that has a crucial role in the worm s life cycle,
In an eight-year survey, at six sites in southern China, Sun and his colleagues found that tree infestation was higher in the presence of a previously unknown species of tree fungus,
"Although we knew that pine-wood nematodes feed on not only the vascular tissue of pines but also tree fungi,
little is known about what the fungi do to either partner in this symbiotic relationship, says Sun. Â To examine the fungi s role in the relationship, the team fed nematodes and beetles with different types of fungus in a Petri dish.
The nematodes feeding on Sporothrix sp. 1 mated more, had more offspring and developed faster than those feeding on other species of fungi."
"The fungus also allowed the beetles to survive better and grow faster, says Sun. The researchers found that Sporothrix sp. 1 also increased the trees'production of diacetone alcohol,
which increases growth and reproduction in the beetles and nematodes. The key now, says Mota,
Fungus threatens top bananaa variant of a fungus that rots and kills the main variety of export banana has been found in plantations in Mozambique and Jordan,
The disease is caused by strains of a soil fungus called Fusarium oxysporum f. sp. cubense (Foc.
if the fungus reaches Latin america, the world s leading banana exporter, says Rony  Swennen of the Catholic University of Leuven in Belgium,
Nobody is sure how the fungus arrived in Jordan or Mozambique. Migrant workers from Asia might inadvertently have brought contaminated soil with them.
but the fungus poses less of a threat to the bulk of the bananas that provide a staple for some 400 Â million people worldwide.
The company plans to sell a mixture of fungi for coating rice and maize (corn) seeds,
such as a symbiotic fungus. Conventional breeding has helped to create varieties with increased tolerance to drought
Only in the 1970s did researchers realize that a fungus living in symbiosis with tall fescue grass was responsible for making cattle grazing on infected pastures ill.
he found that all of them carried a symbiotic fungus. Although neither the plants nor the fungi could tolerate soil temperatures of 40 °C by themselves,
together they could (R.  S.  Redman et  al. Science 298,1581; 2002). ) Rodriguez and his colleagues later discovered that the fungi were easily transferable:
they could grow in anything from watermelons to maize and confer heat-and drought-tolerance on those crops."
) The result is a commercial mix of about half a dozen fungi that the team named Bioensure.
and disease, including pathogens such as wheat rust, an area that Rodriguez says he is pursuing. But
A study in the humid rainforests of Belize shows that plant-killing fungi can help preserve diversity in such ecosystems.
and have begun identifying key fungi in the Belize test plots. Lewis notes that the work could be important for understanding how forests might react to climate change
because fungi are very sensitive to changes in humidity. Scott Mangan an ecologist at Washington University in St louis, Missouri, adds that the Belize study could inform forest-restoration efforts by highlighting the importance of fungi in the soil."
"Before we go into the region that we want to restore, we want to keep in mind that it s not just the trees that are in that area,
mountain pine beetles and blister rust fungus once thwarted by the cold, dry climate have devastated the trees,
And in older forests, fewer large trees dominate growth trends until they are brought eventually down by a combination of fungi, fires, wind and gravity;
Using a technique called bee vectoring researchers force bees to walk through a pesticide before they can exit their hives coating them in a fungus bacterium
For example honeybees or bumblebees can be used to carry natural pest killers like the fungus Beauveria bassiana
The new plants are designed to combat wheat stem rust a fungus that used to take out a fifth of the U s.'wheat crop at once during epidemics through the 1950s.
The rust no longer appears in the U s.)Norman Borlaug the so-called father of the Green revolution
The rust has evolved. And as well as the new Kenyan wheats work now stem rust will evolve again.
In 1999 scientists first confirmed there was a new type of wheat stem rust that infected Borlaug's resistant wheats.
They called the new rust Ug99 after its confirmation year and country Uganda. Since then the rust which moves through the air has spread to Africa and the Middle east.
It affects 37 percent of all the wheat grown in the world the International atomic energy agency estimates.
which point they'll have to create a whole new wheat variety to combat that rust.
International atomic energy agency nuclear radiated biological mutant seed enhancement amplified evolutionary adapation production against wheat rust desease for Kenyan farmers.
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