Like a stealthy enemy, blast disease invades rice crops around the world, killing plants and cutting production of one of the most important global food sources.
Now a study by an international team of researchers has shed light on how the rice blast fungus, Magnaporthe oryzae, invades plant tissue. The finding is a step towards learning how to control the disease, which by some estimates destroys enough rice to feed 60 million people annually.
The team, from the Halpin Laboratory at the University of Exeter, in collaboration with Kansas State University and the Iwate Biotechnology Research Center in Japan, found that the fungus has evolved two distinct secretion systems that facilitate its invasion into rice plants. The results of the study are published in the journal Nature Communications.
Professor Nick Talbot from Biosciences at the University of Exeter said: "This discovery shows that there are two ways in which a disease-causing fungus can secrete proteins into plants. This is a big step forward for plant pathology and might eventually offer new strategies to control crop diseases important in food security. The project was a truly international collaboration with observations being painstakingly checked and validated by students working in different continents over the last two years."Barbara Valent, Distinguished Professor of Plant Pathology at Kansas State University said: "Knowing that a special secretion system is required for disease is significant, because it means we can block this system without harming other fungi that are critical for healthy ecosystems.
Rice blast has been known throughout recorded history and occurs in all countries where rice is grown, including the U.S. In 1985, wheat blast emerged as a new disease sharply reducing wheat yields in Brazil. So far, wheat blast has only spread within South America and has not been detected in the U.S. Valent is now leading a team of scientists focused on developing resources for rapid identification and elimination of the disease if it should arrive in U.S. wheat regions.
Two of the authors on the paper, Yasin Dagdas and Yogesh Gupta, are prestigious Halpin Scholars at the University of Exeter. The Halpin PhD studentship programme, funded by Dr Les and Mrs Claire Halpin, who are alumni of the University of Exeter, trains the next generation of molecular plant pathologists from developing countries in order to build local expertise that can be use to combat rice blast disease and serious agricultural threats to food security. A third student from Exeter, Tom Mentlak, was funded by a prestigious Sainsbury Plant Science Studentship and now works with Cambridge Consultants.
Speaking about their key contributions to the study, Prof. Talbot said: "This work was led at Exeter by three extremely talented students who forged close links with laboratories in the USA and Japan. They worked exceptionally hard and are a great credit to the University."
Rice blast disease is a threat to global food security and is closely related to wheat blast, a newly emerging disease that threatens wheat production in Brazil and which is spreading across South America. Because rice and wheat are the most important food staples worldwide, learning about these diseases is incredibly important to ensuring global food security.
The researchers found that the rice blast fungus Magnaporthe oryzae has evolved a novel secretion system for effectors that go inside the plant cell. In contrast, effectors that end up in the space outside the plant cells are secreted by a classical system, which is shared by organisms from fungi to humans.
In this study, the international team focused on investigating how the fungus secretes effectors during invasion of rice tissue by producing strains secreting effectors linked to fluorescent proteins from jellyfish and corals. They performed microscopy to watch the fungus secreting these fluorescent proteins as it grows inside rice cells, and noticed that normal treatments that block protein secretion didn't stop those effectors that end up inside rice cells.
Identifying how these processes function will advance understanding of how disease micro-organisms evolve and will prove pivotal in controlling blast disease.
About the University of ExeterThe Sunday Times University of the Year 2012-13, the University of Exeter is a Russell Group university and in the top one percent of institutions globally. It combines world-class research with very high levels of student satisfaction. Exeter has over 18,000 students and is ranked 7th in The Sunday Times University Guide, 10th in The Complete University Guide, 10th in the UK in The Times Good University Guide 2012 and 12th in the Guardian University Guide 2014. In the 2008 Research Assessment Exercise (RAE) 90% of the University's research was rated as being at internationally recognised levels and 16 of its 31 subjects are ranked in the top 10, with 27 subjects ranked in the top 20.
For further information:Dr Jo Bowler
Jo Bowler | EurekAlert!
Alkaline soil, sensible sensor
03.08.2017 | American Society of Agronomy
New 3-D model predicts best planting practices for farmers
26.06.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
23.08.2017 | Life Sciences
23.08.2017 | Life Sciences
23.08.2017 | Physics and Astronomy