Evolution is in a perpetual cycle of churning out new pathogens. Luckily for us humans and many other animals, we have a very advanced immune system — known as the adaptive immune system — that allows our bodies to very precisely target pathogens using antibodies and a whole host of other weapons, like T cells. When we get vaccinated against a disease-causing organism such as measles or COVID, we are prepping this adaptive immune system for future encounters with the pathogen.

Plants lack this. While they do have a more general immune system — known as innate immunity — it is not nearly as precise or powerful as adaptive immunity. While this innate immune system has withstood the test of time, it leaves plants, including important food crops, vulnerable to new strains of pathogens.

What if it was possible to bioengineer plants to have an adaptive immune system? That’s precisely what Jiorgos Kourelis and his colleagues did, and their results were reported in the journal Science. Their method could provide a path toward the long-sought goal of rapidly and precisely modifying susceptible crop species to give them resistance to emergent pathogens and pests.

An evolutionary dance

Plant immunity can be divided into cell-surface and intracellular immunity. Coating the surface of plant cells, immune receptors monitor for