UV Light May Help Farmers Vanquish Deadly Cantaloupe Pathogen

Jim Rogers Florida

University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) scientists want to help Florida farmers and U.S. producers grow a cantaloupe to satisfy consumers’ tastes and one that’s protected against powdery mildew disease.

Cantaloupe research
Photo courtesy of UF/IFAS.

Even with fungicides, producers struggle to control powdery mildew, a disease that can damage or kill the fruit. Thanks to UF/IFAS research, growers may now implement ultraviolet (UV) light as part of their management tactics.

Natalia Peres, a UF/IFAS plant pathology professor, has published a new study that shows UV light can zap the pathogen on the plants without damaging them.

“Powdery mildew is one of the most common and severe diseases of cucurbits worldwide,” said Peres, a faculty member at the UF/IFAS Gulf Coast Research and Education Center (GCREC). “It can be a major disease on cantaloupes grown in Florida, although there are some cultivars that tolerate it better.”

Powdery mildew can survive natural UV light in sunlight. The disease can fight the natural UV light of daytime, but not at night.

“If we applied UV light during the day, we would need to use higher doses to get the same effect,” Peres said.  “However, these natural defenses are not active at night, so by applying UV light at night, we can bypass the natural defenses of the pathogen and kill it with lower doses that we would need during the day.”

That’s why scientists put an ultraviolet lamp behind a tractor, drove it onto the GCREC research farm once or twice a week (overnight), aimed the light at the cantaloupe and struck the mildew out of the plant.

“Our unit was built in a shop by one of our strawberry growers,” Peres said. “Similar and bigger units could be designed and built for growers to use at their farms.”

No commercial units are available for field applications – yet, but there is plenty of research recently on the use of UV light in agriculture systems.

Cantaloupe production in Florida is mostly concentrated in Collier, Hendry, Hardee, Manatee and Hillsborough counties. Florida farmers harvest cantaloupe from mid-March through May. The U.S. Department of Agriculture NASS State Agriculture Overview for Florida shows that the state’s growers harvested 1,500 acres of cantaloupe in 2021. That equates to about 375,000 pounds, worth just under $10 million annually.

Source: UF/IFAS