Scientists at The James Hutton Institute, working with partners from the University of York and the Université Libre de Bruxelles, have uncovered how one of the world’s most destructive plant diseases evades crop defences — a breakthrough that could help farmers cultivate stronger, more resilient plants.
The study, published in Nature Communications, identifies a family of enzymes produced by Phytophthora infestans, a persistent pathogen that threatens potato and tomato crops globally.
The researchers found that this microorganism uses specialised enzymes, known as AA7 oxidases, to disrupt plants’ early warning systems, weakening their defences before they can respond. Crucially, when the genes responsible for these enzymes were disabled, the pathogen lost its ability to infect its host.
The James Hutton Institute is a world-leading centre for research focused on global food security, delivering scientific solutions for the sustainable management of land and natural resources, and supporting advances in agricultural productivity and crop resilience, according to a press release.
Dr Federico Sabbadin, from the University of York’s Centre for Novel Agricultural Products (CNAP), said: “It’s like burglars cutting the wires to your home alarm before breaking in. The trick is that the pathogen has evolved the same kind of enzyme activity that plants themselves use to keep their alarm signals under control.
“By attacking these alarm molecules, the pathogen switches them off before the plant can react — it’s as if the microbe has learned the plant’s own language and uses it against it. When we disabled the genes for these enzymes, the microbes became much weaker at infecting plants.”
As climate change drives more extreme weather and disrupts farming systems, crops are becoming increasingly vulnerable to pests and disease. With global food demand continuing to rise, each lost harvest heightens the risk of shortages and escalating prices.
By revealing this previously hidden microbial strategy, scientists have created new opportunities to strengthen crop protection. Targeting the AA7 enzymes could help keep plants’ defences active, enabling farmers to safeguard yields in an increasingly unpredictable climate.