As rust fungi attack, they turn on and off particular genes in wheat to prevent the plant from defending itself. When successful, this stops the plant from killing the invading fungus and ultimately leads to severe plant disease.
Researchers from the John Innes Centre have found that deleting a gene in wheat helps to promote greater resistance to attack from yellow rust and stem rust.
Dr Pilar Corredor-Moreno, a researcher on the project, said: “We were amazed to see that removing just this one gene in our mutant plants caused them to alert their defence responses even before they were under attack.
“This likely helped the plants to give a much speedier defence response, curtailing rust infection before it even had a chance to start.”
Disrupting the function of this gene provides resistance to two of the most economically damaging diseases of wheat worldwide – yellow and stem rust.
Further analysis of the TaBCAT1 gene showed that it takes part in the break-down of a particular group of amino acids called branched-chain amino acids. The team also found that the amount of these amino acids was different in wheat plants during successful and unsuccessful rust infections, showing that their amount could be important for the invading pathogen.
Dr Diane Saunders, who oversaw the project, said:, “This study may well have identified an Achilles’ heel for rust infection. It will be exciting to explore this gene further with our wheat breeders as a potential new source of resistance to these notorious diseases of wheat that cause severe crop losses across the world.”