Glowing plants created to protect our crops

A study led by the Research Institute for Molecular and Cellular Biology of Plants (IBMCP), a joint centre of the Spanish National Research Council (CSIC) and the Universitat Politècnica de València (UPV), has developed a method for monitoring and controlling pests and diseases in crops through glowing plants. Using a light-emitting mechanism inspired by fungi, the researchers have developed a bioluminescent system in which a plant emits one type of light when healthy and another when infected by a virus – a change detectable with conventional cameras before symptoms of the disease appear. This biological light-emitting infection detector has been published in *Nature Communications*.

"We have created plants that glow in the dark and which, furthermore, change colour when infected by a virus," explains Diego Orzáez, a CSIC researcher at the IBMCP and one of the study's lead authors. The work is based on the bioluminescence system found in fungi: four enzymes convert a natural compound in the plant (caffeic acid) into a molecule which, upon oxidation, emits a steady green light. "Using the same mechanism that makes certain fungi glow, we have genetically programmed tobacco plants to emit a continuous yellow light, like an 'indicator light' showing that everything is working properly. When a virus infects them, that light turns green. An automated camera system can detect the infection before any visible symptoms appear," he explains.

The research team demonstrated the system's effectiveness in transgenic Nicotiana benthamiana plants, a tobacco relative commonly used as a model plant in research. First, they introduced genes from the fungi's bioluminescence system into the plant using modified viruses, making it easier to monitor infection visually and affected areas. They then developed a sentinel system with two distinct signals to indicate infection by potyviruses — the largest genus of plant-infecting viruses, which includes some of the most damaging to agriculture — through a change in the colour of the light emitted by the plant.

Integrated pest detector

When no infection is present, the plants emit a steady yellow light, indicating that the system is functioning correctly. However, if the plant becomes infected with potyviruses, a viral enzyme triggers a colour change in response to light, which can be easily detected with low-cost devices. "The colour change is virus-specific and detectable with a conventional camera," says Orzáez. "We have also tested the system in a mixed-cropping scenario, interplanting these sentinel plants with experimentally infected tomatoes, and the plants detected the infection before the tomatoes showed any visible symptoms," notes the CSIC researcher.

Current plant diagnostic methods, such as PCR and ELISA—which detect viral genetic material or its proteins, respectively—are renowned for their accuracy. However, they require time, specialised staff and laboratory facilities. "Our plant, by contrast, monitors the infection continuously and autonomously, without needing external reagents or taking samples," explains Marta Vázquez, a postdoctoral researcher at the IBMCP and lead author of the study. "Furthermore, the dual-output design with two distinct colours minimises false negatives, as if the plant stops glowing completely, this is also a warning sign. It is like a biological smoke detector integrated into the crop itself," she points out.

Early monitoring in greenhouses and crops

Among the applications of this system, the most immediate is the early detection of viral diseases in greenhouses and other controlled environments, where simply interspersing a few sentinel plants among the crop would be sufficient to detect outbreaks before they spread. In the long term, the same principle can be adapted to other viruses, and even to bacteria or fungi that possess similar enzymes. It also has potential in the context of climate change, where the arrival of new invasive pathogens makes early detection increasingly urgent.

This research has been funded by the Ministry of Science, Innovation and Universities through the State Research Agency, by the Valencian Regional Government and by the European Union through the European Regional Development Fund (ERDF) programme. The study is a collaboration between the Margarita Salas Centre for Biological Research (CIB-CSIC), the Central Unit for Medical Research at the University of Valencia and the MRC Laboratory of Medical Sciences in London.

Reference

Calvache, C., Rodriguez-Rodriguez, M., Vazquez-Vilriales, V. et al. Bioluminescent sentinel plants enable autonomous diagnostics of viral infections. Nat Commun. DOI: https://doi.org/10.1038/s41467-026-73810-w