UF-developed web tool helps blueberry growers control diseases
Anthracnose fruit rot affects blueberries, especially in Florida. In fact, it is one of the most damaging diseases of fruit.
To control the disease, farmers usually spray the crop with fungicides, but on a regular basis, ie every two to three weeks.
So a few years ago, scientists at the University of Florida developed the Blueberry Advisory System, a tool to help blueberry growers combat fruit rot through an alert system.
Researchers now have proof that the system works to help minimize fruit rot and improve crop yields.
When flowers and fruit are developing, many farmers use a calendar-based method of spraying their plants to protect against rot. With the Blueberry Advisory System, they spray when the tool sends them alerts. Notifications are received by text message or email.
Growers can also use risk assessments to choose whether to use a less expensive fungicide when facing moderate disease risk, or a more effective but also more expensive product during periods of high risk.
“Several commercial Florida blueberry growers have reported using the Blueberry Advisory System to help with timing of fungicides to control anthracnose fruit rot, either using the web-based tool alone or in combination with farmers' own spray programs," said Doug Phillips, UF/IFAS Blueberry State Extension Coordinator.
Clyde Fraisse, a UF/IFAS professor of agricultural and biological engineering, designed the Agroclimate system that houses this and other disease tools. Natalia Peres, a professor of plant pathology at the UF/IFAS Gulf Coast Research and Education Center, adapted and evaluated the disease models used in the system.
Peres describes the success of the method in a new UF/IFAS extension document .
"The system can be especially useful in helping new blueberry growers identify the disease and its dynamics," Peres said. "It can also reduce the number of fungicide applications, especially when adopted by risk-averse growers."
She and her research colleagues evaluated the system on nine blueberry farms spread across Dade City (Pasco County), Fort Lonesome (Hillsborough County), and Labelle (Hendry County).
The results were good. The system notified growers to spray fungicide when fruit rot was most likely to develop and, in most cases, they did not need to spray as often.
Any method that helps combat disease is vital to the efforts of Florida farmers who grow blueberries. The season (from bloom to harvest) runs from December to May and includes about 5500 acres, with an annual value of $62 million.
Blueberries are most susceptible to fruit rot in hot, humid climates, with temperatures between 59 and 81 degrees. Combine those conditions with 12-hour periods of leaf wetness and you have ideal conditions for fruit rot to develop.
The data for the fruit rot models used by the system comes from the Florida Automated Weather Network, which has weather stations across the state.
Rain or overhead irrigation can exacerbate the problem by spreading the pathogen to healthy fruits and plants, creating additional opportunities for infection. The pathogen can also be spread when fruits touch each other and by harvesting machinery and grading equipment.