NORWICH, UNITED KINGDOM — Researchers at the John Innes Centre in Norwich in eastern England have developed a new mobile surveillance technique that gives them the ability to identify specific wheat rust fungus strains within 48 hours of collecting a sample. The new digital platform significantly reduces the time to identify strains, which previously took months.
“Knowing which strain you have is critical information that can be incorporated into early warning systems and results in more effective control of disease outbreaks in farmer’s fields” said Dr. Dave Hodson, a rust pathologist at CIMMYT in Ethiopia and co-author of the paper “MARPLE, a point-of-care, strain-level disease diagnostics and surveillance tool for complex fungal pathogens.” The paper recently was published in BMC Biology.
The technology is known as the MARPLE (Mobile And Real-time PLant disEase) diagnostic platform. The researchers said the platform targets parts of the rust genetic code that can be sequenced on a portable MinION sequencing platform from Oxford Nanopore.
“This helps us tell strains apart and quickly recognize those we’ve seen before or spot new ones that could be a new threat,” said first author. Dr Guru Radhakrishnan from the John Innes Centre.
Dr. Diane Saunders, lead author and group leader at the John Innes Centre, added, “The challenge is that tracking the wheat rusts is not as simple as you would expect. There are many different strains, all with unique characteristics that cannot be told apart without lengthy in-lab tests. Consequently, identifying which ones are a threat can take many, many months, likely by which time the infection has spread.”
A key benefit of the technology is that MARPLE diagnostics was designed to operate directly in the field. Previously, researchers would have to ship samples to specialist laboratories, which often would lead to lengthy time delays in getting back results.
The researchers said the new platform now allows research groups to coordinate more closely with government ministries and national breeding programs to protect local farmers.
“This is real national and international work that ultimately helps the resource-poor farmers,” said Dr. Badada Girima, rust pathologist, Delivering Genetic Gain in Wheat program.
The technology has been used in fields in Ethiopia, and more field stations across Ethiopia are expected to be setup to use the MARPLE mobile lab, the researchers noted.
The researchers earlier this year were awarded Innovator of the Year for international impact from the Biotechnology and Biological Sciences Research Council.