Florida's strawberry growers are embracing a forecasting tool to better manage their fungicide sprays against anthracnose and botrytis fruit rots.
The Strawberry Advisory System uses data from six weather stations in the state's main strawberry producing areas to predict when environmental conditions favor outbreaks of these two diseases, says Natalia Peres, associate professor of plant pathology at the University of Florida's Gulf Coast Research and Education Center in Wimauma.
Growers can check the website (agroclimate.org/tools/strawberry) for a color-coded update from their nearest weather station: green for low risk, red for high risk and yellow for moderate risk. For more immediate updates, they can opt to receive text or email alerts.
System gains popularity
So far, 55 growers representing about half the state's industry have signed up, Peres says.
The system also provides spray recommendations, based on when the field was last sprayed and with what fungicide. Other factors considered are whether plants have hit peak bloom and whether symptoms are present.
"Growers need to be very quick on their response" to anthracnose and botrytis, Peres says. "When the system says conditions are favorable, [disease development] is already started."
"You've got to get the materials on at the right time," says Carl Grooms, owner of Fancy Farms in Plant City. "You don't take aspirin this week to deal with next week's headache."
Over the past five years, Grooms has used the forecasting tool to manage fungicide applications on an increasing proportion of his farm. Now he's committed his entire 50 acres of strawberries.
"For years we've been putting out [fungicide sprays] on a time basis, once a week," he says. "Now through the model we understand sometimes we can get by without an entire spray."
"It's been a significant tool," says Dudley Calfee, general manager at Ferris Farms in Floral City. He estimates the company has cut the number of fungicide sprays by 30 percent to 50 percent.
Reducing applications not only saves money but also helps combat strawberries' image with consumers as a pesticide-intensive crop, he says.
Another benefit is extending fungicide usefulness through better resistance management, Grooms says.
Fungicide resistance is an ongoing concern, with many of the current materials—including Pristine (a mix of boscalid and pryaclostrobin), Elevate (fenhexamid), Scala (pyrimethanil) and Topsin M (thiophanate-methyl)—showing signs of reduced efficacy, Peres says.