An international consortium of scientists and manufacturers have pioneered a revolutionary treatment for fungal diseases common to agriculture.
The group, which includes researchers at Cornell AgriTech in New York, the University of Florida and Norwegian firm SAGA Robotics, have developed a robot that uses ultraviolet (UV) light lamps to eliminate mildew from vineyards.
According to project leader David Gadoury, their preliminary trials involved using an array of UV lamps mounted on a tractor wagon. The University of Florida tested the technology on strawberry plants – with impressive results.
Further testing on Chardonnay vineyards in 2019 also gave convincing evidence that UV light is an effective treatment for fungal diseases.
“In a sense, this project has been over 28 years in the making,” said David Gadoury, senior research associate in the Department of Plant Pathology at Cornell. “We started doing initial trials with UV light back in 1991. However, although it was successful in destroying the fungal cells, it also did irreparable damage to the plants. So we abandoned the idea.”
The project was resurrected in 2010 when one of Gadoury's Norwegian colleagues proved that the treatment could be used without damaging the plant's cells.
“A PhD student called Aruppillai Suthparan demonstrated that the treatment had to be applied at night,” explained Gadoury. “These fungal pathogens have an inbuilt defence mechanism against naturally-occurring UV light – they use blue light emitted during the day to repair their cell damage. But at night this defence collapses. So only a small dose of UV light is needed, which is effective in killing single-cell organisms, but doesn't harm the crops.”
Gadoury and other scientists partnered with the robotics firm SAGA to develop an automated delivery system. The prototype, called Thorvald, is a lightweight robot that can be equipped with up to 30 UV lamps.
Crucially, its dimensions can be adapted to treat a variety of agricultural crops.
“Thorvald uses a very sophisticated GPS system and is almost totally autonomous," said Gadoury. “After the grower programs some basic vectors, it can then work autonomously all through the night, seven days a week. The operating speed is five miles per hour – far quicker than any existing technology.”
He added that collaborations with other universities have also led to UV trials with squash, pumpkins, cucumbers, hops, basil and industrial hemp.
Initial research also suggests that in addition to killing fungi, UV treatments can also reduce pest populations – studies have shown that treatment with two different ultraviolet rays (UVB and UVC) can kill the eggs of spider mites and red mites.
Gadoury estimates that the project's research and development cost is at least $6m. Several of the Thorvald robots have already been bought by research institutions.
“I would expect each robot prototype to retail for approximately (the figure is far from exact) $60,000,” said Gadoury. “SAGA is currently investigating the logistics of manufacturing the robots on a larger scale. When that happens, we expect the market to react very positively. The existing technology out there is very slow and cumbersome – our robots can cover 30 hectares in one evening. This is the future.”