DARPA engineering smart plants to act as biosensors
- By Michael Peck
- Dec 07, 2017
The Defense Advanced Research Projects Agency is exploring how plants can be genetically modified to detect chemical, nuclear or biological threats that waft through the air.
The Advanced Plant Technologies program aims to harness plants' built-in mechanisms for responding to their environment and extend those abilities so the they could "detect the presence of certain chemicals, pathogens, radiation, and even electromagnetic signals," DARPA said in its recent DARPA announcement.
The idea isn't exactly new. Biologists have already proposed planting smart gardens at airports that could detect drugs and explosives. Others advocate using plants to detect pollutants in the air.
But for DARPA and the military, plant-based sensors are cheap, relatively self-sustaining, hardy and unobtrusive. Plants also naturally react to certain stimuli. Genetic engineering would allow the military to determine which stimuli spark a plant's reaction.
“Plants are highly attuned to their environments and naturally manifest physiological responses to basic stimuli such as light and temperature, but also in some cases to touch, chemicals, pests, and pathogens,” said Blake Bextine, DARPA's APT program manager.
While DARPA may be pushing the limits of biology, it will be more conservative on data collection, relying on existing ground-, air-, and space-based technology for remote monitoring. "Such systems are already capable of measuring plants’ temperature, chemical composition, reflectance, and body plan, among other qualities, from a standoff distance," DARPA said.
DARPA officials acknowledged there are challenges in keeping those leafy sensors alive, such as understanding how plants allocate their biological resources, and how they survive in the wild. "Past experiments of this type have reduced the fitness of modified plants by siphoning resources needed to sustain the plants," the agency noted. "APT will seek to improve how plants collect and distribute resources, and optimize their fitness so that modified plants thrive despite anticipated interactions with natural stressors such as microbes, animals, insects, and other plants."
Initial research will be performed in contained laboratories and greenhouses overseen by "institutional biosafety committees." If the initial work proves successful, follow-up trials will be conducted under the auspices of the Department of Agriculture’s Animal and Plant Health Inspection Service.
DARPA appears to be anticipating an almost inevitable public backlash. Earlier this year, a genetics scientist warned that DARPA's synthetic biology research could violate international environmental treaties and risk unanticipated effects on ecosystems.
On the other hand, the research agency pointed out that it is expensive and complicated to maintain networks of mechanical and electronic sensors. A genetically modified plant could be a much less expensive option for distributing sensors and collecting data over a wide area.
This article was first posted to Defense Systems, a sibling site to GCN.
Michael Peck is a freelance contributor to Defense Systems.