A fungus is threatening the world’s food supply. Scientists just found a new defense
Scientists have discovered a potential new weapon against a devastating fungus that threatens rice, wheat, and barley worldwide. By engineering a special type of plant immune receptor, researchers created defenses capable of recognizing multiple fungal threats at once. The breakthrough could eventually lead to crops with powerful, long-lasting disease resistance, helping protect a global food supply increasingly…
Key points
- Scientists at the John Innes Centre have engineered plant immune receptors to recognize two fungal effectors linked to wheat and barley infections.
- Rice blast destroys enough rice each year to feed approximately 60 million people.
- The engineered receptors have only been tested in individual wheat cells, with whole-plant greenhouse trials still to come.
Researchers led by the John Innes Centre in the United Kingdom have developed an experimental way to strengthen crop defenses against a fungus that threatens global food security. The team studied a recently discovered group of plant immune receptors and showed they can be modified to detect multiple fungal threats, according to findings published in Science Advances.
The work involved collaborators at Kobe University in Japan and focused on Magnaporthe oryzae, the fungus that causes blast disease. The disease is the most serious fungal infection of cultivated rice and has also become a major threat to wheat and barley in parts of Asia and Africa.
How the receptors work
The fungus infects plants by delivering specialized molecules called effectors into leaf and stem cells, interfering with normal plant functions. Plants can counter this through immune receptors that recognize the foreign molecules and trigger a protective response, including localized cell death that limits the pathogen's spread.
Much research has centered on proteins called Nucleotide-binding and leucine-rich receptors (NLRs). Scientists have more recently begun studying tandem kinase proteins (TKPs) in cereal crops. Some TKPs contain a region called a Heavy Metal Associated (HMA) domain, also found in certain NLRs, where it helps recognize pathogen effectors.
Using biophysical techniques and crystallography, the team obtained a high-resolution view of how HMA domains bind fungal effectors. The results showed the domains can act as biological bait, helping plants detect an invading pathogen and activate defenses. The researchers then modified TKP receptors to recognize two different fungal effectors tied to wheat and barley infections, an unusual ability called dual specificity.
We've discovered something that could lead to a potential intervention on what is the worst fungal disease of cereals
— Professor Mark Banfield
Early stage of the research
The initial tests used protoplasts, individual wheat cells serving as a simplified model. The next step is to determine whether the engineered receptors protect whole plants grown under controlled greenhouse conditions.
Wheat blast was first identified in Brazil during the 1980s and has since spread to parts of Asia and Africa. It has not been detected in the United Kingdom, though climate change could eventually create conditions that allow it to threaten cereal production in northern Europe.
What researchers said
"We've discovered something that could lead to a potential intervention on what is the worst fungal disease of cereals," said Professor Mark Banfield, a research group leader at the John Innes Centre and an author of the study.
Dr. Daniel Yu, the first author, said the study shows the new class of resistance proteins can be engineered and that tools previously used on NLR receptors may also work with it. Banfield added that combining NLRs and TKPs could give more robust immunity because the two classes are probably activated in different ways.
