The spread of exotic and aggressive strains of a plant
fungus1 is presenting a serious threat to wheat production in the UK, according to research published in Genome Biology. The research uses a new surveillance technique that could be
applied2 internationally to respond to the spread of a wide variety of plant diseases. Wheat is a critical
staple3 and provides 20% of the calories and over 25% of the protein consumed by humans. 'Yellow
rust4' caused by the fungus Puccinia striiformis f. sp. tritici (PST) is one of the plant's major diseases and is widespread across the major wheat-producing areas of the world. Infections lead to significant reductions in both grain quality and yield, with some rare events leading to the loss of an entire crop. New fungus strains have recently emerged that adapt to warmer temperatures, are more aggressive and have overcome many of the major
defensive5 genes6 in wheat.
Lead author Diane Saunders of the John Innes Centre and The Genome Analysis Centre (TGAC), UK, said: "Increased
virulence7, globalization, and climate change, are all increasing the scale and frequency of emerging plant diseases, and threatening global food security.
"Our research shows that in the UK we have a newly emerging population of wheat rust fungus that could be the result of an
influx8 of more exotic and aggressive strains that are displacing the previous population. By continuing to use these new surveillance techniques, not only can we track and respond to the
ongoing9 threat of wheat rust, but our technology opens the door for tracking other plant pathogens, including ash dieback."
Researchers from the John Innes Centre, The Sainsbury Laboratory, TGAC and the National Institute of Agricultural Botany sequenced
genetic10 material from 39 PST-infected samples of wheat collected from 17 UK counties in 2013.
By comparing the fungal RNA with fungal genetic information from
previously11 prevalent populations between 1978 and 2011, they showed that there has been a rapid and dramatic shift in the PST population that could have serious implications for wheat production in the UK.