When a crop gets diseased, it can spread really quickly in a field, so it’s essential for farmers to detect problems fast.
But, traditional methods of disease detection can take weeks. Now a team of NC State researchers have come up with something that’s much quicker and portable.
The device literally smells disease.
Currently, it’s being tested in a lab run by assistant professor Qingshan Wei of the Emerging Plant Disease & Global Food Security Cluster at NC State.
They’ve detailed their results in a paper published by the Journal Nature.
Here’s how it works in laymen’s terms.
When a plant is diseased, it will actually give off gasses.
To test their proof of concept, Wei’s team puts part of a tomato plant leaf in a sealed glass tube.
The wait about 15 minutes as the air in the sealed vial becomes saturated with volatiles from the plant.
Once enough gas is collected, a device attached to the back of a cell phone is used to suck the air from the vial into a chamber where it’s analyzed.
The gas reacts with a tiny paper strip that’s coated with chemical dots.
The dots change color based on the disease affecting the plant.
The cell phone user then takes a magnified picture of the strip to be used by them as a reference on what chemical treatments need to be applied to the crops to stop the spread of disease.
“You want to know if it’s a bacterial infection or a fungal infection or other type of infection and guide your treatment steps,” said Wei.
Right now, the sniffer device only works on potato leaves and tomato leaves, but Wei’s team is developing sensors which will work with other crops.
The idea for the sensor was built on previous discoveries by other researchers who found out diseased plants gave off certain gasses.
“The leaf is breathing,” said Wei. “It’s exchanging molecules with the air.”
Right now, a farmers only options for figuring out what’s plaguing a crop is either guesswork or sending a sample to as clinical lab where it can take weeks to figure out the pathogen affecting the plants.
By the time the results are sent back to the farmer, the disease could have ruined an entire field of crops.
Once this lab porotype is fully developed, farmers will be able to use it in their fields to get instant results and can minimize the amount of chemical they apply.
“You want to have a rapid decision if you want to apply a fungicide or not,” said Wei.
Deciding how much and what chemical to apply is important because the less that’s applied is better for the environment.
And, saving a crop early will end up keeping prices lower because farmers won’t lose as much in the field.
Actual use of the sniffer is still about a year or so away because as it still needs a little more testing.