University of Georgia developing sensors to detect stressed plants

Researchers at the University of Georgia are developing an “electronic nose” that may help lower the use of pesticides, herbicides and fungicides, in addition to saving farmers money.

The tool in development detects compounds, called green leaf volatiles, emitted by plants in distress from disease or other external forces. The compounds are invisible and odorless to humans and often released before outward signs of trouble show.

“The sensor works based on electrochemical detection principles,” said Ramaraja Ramasamy, assistant professor of engineering at the university. “We would like to achieve ultra-low detection limits in addition to achieving highly selective detection of the target volatile of interest.”

The researchers note that the volatiles emitted by plants vary depending on the type of stress experienced, which could one day widen their focus.

“Right now we are interested in the fundamental science behind the sensing, rather than the type of chemical itself,” Ramasamy said. “We chose to work with a specific chemical as our target compound for detection. It has been established that this chemical is released by pepper plants when they are infected by fungal pathogens.”

Crop loss and disease transmission can be diminished by detecting pathogens and other problems earlier than humanly possible. Other beneficial applications of the technology could include use by distributors to catch unhealthy fruits and vegetables before they are sent to market.

The sensors could also be employed in a grid pattern to quarantine harmful agents in one section of a field, localizing and reducing the application of crop treatments, estimated to cost American farmers nearly $33 billion each year.

Though the potential payoff of deploying the sensor looks promising, the research team is mindful to keep the associated costs low.

“It is too early to make an estimation on this (deployment cost), but our goal is to use materials and components that would make it affordable for practical applications,” Ramasamy said.

An article describing the research is published in the journal Analyst.

Image credit: Huw Williams via Wikimedia Commons.