and The Sainsbury Laboratory Norwich looked in unprecedented detail at how Phytophthora infestans a pathogen that continues to blight potatoes
The study published today in the journal Science is the first to show how pathogens switch from targeting one species to another through changes at the molecular level.
and sister species Phytophthora mirabilis a pathogen that split from P. infestans around 1300 years ago to target the Mirabilis jalapa plant commonly known as the four o'clock flower.
They found that each pathogen species secretes specialised substances to shut down the defences of their target hosts'Plants have called these enzymes proteases that play a key role in their defence systems'said Dr Renier van der Hoorn co-author of the study from Oxford university
'When a plant becomes infected proteases help plants to attack the invading pathogens and trigger immune responses.
'We looked at specialisation in the blight pathogens'secret weapon a key family of effectors called'EPIC'that can pass through plants'defences undetected to disable the proteases.
and destroy the pathogen. Potato and tomato plants with such proteases would be resistant to the blight pathogens
and combined with other resistant traits could provide another'wall'of defence against the pathogens.'
'Story Source: The above story is provided based on materials by University of Oxford. Note: Materials may be edited for content and length.
However assessing disease resistance in young oilseed rape plants is difficult as there is a long period where the pathogen is not visible--it can infect plants
'Oomycetes are potent pathogens that can cause seeds and seedlings to rot and were responsible for the 1840s potato famine'said Professor Sarah Gurr formerly of Oxford university and now at the University of Exeter.'
#Pathogenic plant virus jumps to honeybees, may explain bee population declinea viral pathogen that typically infects plants has been found in honeybees
and is less resistant to pathogens and pests. â#oefor a long time cotton breeders have been trying to develop upland cotton with the fiber qualities of barbadense cottonâ#Pepper said. â#oeglobally everybodyâ##s trying to do it.
Researchers at the Max Planck Institute for Chemical Ecology in Jena Germany have now found that ants also keep harmful leaf pathogens in check.
Study results indicate that symbiotic bacteria colonizing the ants inhibit pathogen growth on the leaves.
whether the tiny bodyguards also provide protection against microbial pathogens. They compared the leaves of acacia plants
and microbial pathogens than did the leaves that had mutualistic ants. The presence of the right symbiotic partner seemed to have a positive effect on the plant's health.
Analysis of the surfaces of the leaves revealed that the number of plant pathogens as well as of necrotic plant tissues increased considerably
which regulates defense against pathogens. Detailed analysis of the bacterial composition on the surfaces of the leaves suggested that the presence of mutualistic ants changed the bacterial populations and reduced harmful pathogens.
Although far less pronounced this effect could also be observed in parasitic ants. How antimicrobial protection is transferred from ants to plant is still unclear.
and parasitic ants and tested the effect of the extracts on the growth of bacterial pathogens in the lab. Plant pathogen Pseudomonas syringae was sensitive to the application of leg extracts of both ant species
The bacterial genus Burkholderia for example includes dangerous disease-causing pathogens--one species has even been listed as a potential bioterrorist agent
Unlike their dangerous cousins the four symbiotic Burkholderia species did not have associated genes with the virulence systems found in the pathogenic species. Burkholderia were discovered first as plant pathogens in 1949 by Walter Burkholder who identified them as the agent causing
Other Burkholderia belong to the Burkholderia cepacia complex a group of related bacteria that are not true pathogens
It wasn't until many decades after Burkholder's discovery that closely related Burkholderia species were found to enter plant roots not as pathogens
pathogens or weeds that could harm local crops. Led by USDA plant geneticist Stephanie Greene and St petersburg State university scientist Alexandr Afonin,
That ability helps the pathogen to outsmart its plant hosts. Now discovered it may clue researchers into unlocking ways to control it.
This pathogen has an exquisite ability to adapt and change, and that's what makes it so dangerous,
As the team sequences additional strains and close relatives of the pathogen they'll be able to develop a more comprehensive understanding of the blight's adaptation.
The findings reveal the pathogen's unusual strategy to support the rapid evolution of critical genes, known as effector genes,
it is more likely to be pathogen-free. They read any books and papers they can find on the subject,
whether that food is harboring a dangerous pathogen. Researchers are designing packaging that could alert consumers to a pathogen in the food
or to a food product that s nearing the end of its shelf life, Cooksey said. A French company has developed a sensor that can detect
Researchers are working on an antimicrobial film that would go inside food packaging to provide an extra barrier against pathogens.
Better still, the permanent etching-hence tattoo--does not increase water loss, nor the entrance of food pathogens or postharvest pathogens.
stopping decay and food pathogens. Wax coverage is recommended still to prevent water loss. To test for decay, the fruit was inoculated with decay organisms and then etched with the laser.
No pathogens were found in the peel or the fruit interior. So how does it work?
So it may have the ability to turn into a real bona fide human pathogen. That is why we continue to monitor this in the bird populations,
I personally believe that they probably have the ability to become a human pathogen. What can we do to prevent a pandemic?
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