Immunizing plants by airmail

Scientists from Helmholtz Zentrum München are a step closer to enable new ways for enhancing plant fitness and yield in the face of increasing pathogen pressure. Potentially this will have significant impact on environmental as well as human health. Climate change is expected to lead to severely increased disease pressure on crop plants. It is therefore of the utmost importance to understand plant immunity and to find ways of fortifying plants against disease. Their work has been published in Nature Communications.

© Helmholtz Zentrum München

Similar to that of animals and humans, the plant immune system ‘remembers’ prior attacks by pathogens, resulting in systemically enhanced immune readiness. Additionally, plants warn each other in the event of imminent danger using airborne signals.

Now Dr. Corina Vlot-Schuster, Institute of Biochemical Plant Pathology (BIOP), together with colleagues from the Research Unit Experimental Environmental Simulation (EUS) and from Mc Master University, Canada, has exploited this behavior to find ways to generate a kind of targeted immunization of plant populations. As model organism they used Arabidopsis.

"A stress situation is normally associated with an increased susceptibility to infection," explains Vlot Schuster, head of the inducible resistance laboratory at BIOP, "our goal was to prepare the plants so that they are more resistant against infection. This would make plants such as barley better prepared for the challenges of climate change".

The researchers copied the plants' behaviour by using volatile messengers as an early warning system. The results showed that systemic immune signals not only act within an organism, but also support communication between plants. All affected plants activated their immune systems and themselves released volatile messenger substances. In this way, the airborne warning signals were transmitted to more distant individuals, and this could result in the protection of, for example, an entire grain field.

"The investigations revealed that it is possible to induce increased defence reactions in plants and to use this like a multiplier," says Prof. Dr. Jörg-Peter Schnitzler, head of EUS.  For example, it would be conceivable to equip an area within a grain field with plants that emit volatile warning substances. This would increase the immunity of the neighbouring plants around these 'warning islands', and thus perfectly prepare the majority of the plants in the vicinity for an extreme or stress situation.

"With this method, ways could be found to make crops more robust and adaptable to the challenges of climate change without usage of pesticides," explains Marion Wenig, BIOP, first author of the study. "Our next aim is to use this approach to increase the yield and stability of crops, especially cereals," adds Vlot-Schuster.

More Information

Originalpublikation:
Marion Wenig et al. (2019): Systemic acquired resistance networks amplify airborne defense cues. Nature communications
Doi: 10.1038/s41467-019-11798-2