In a recent webinar, Jim Adaskaveg, University of California, Riverside professor and plant pathologist, discussed some recently registered fungicides to manage phytophthora and other fungal diseases of citrus. Orondis was registered in 2018, Presidio in 2019 and Revus in 2020. Adaskaveg said Orondis and Revus each contain a new active ingredient with a different mode of action and provide a …
Copper Fungicides: The Essential Tool for Citrus Growers
One of the main issues for citrus crop growers is the quick spread of fungal and bacterial diseases due to warm, wet growing conditions. Without proper methods to prevent and control diseases, crop yield can be greatly reduced, and groves can become ruined. How do you produce a healthy citrus crop while keeping diseases under control? For generations, growers have …
Benefits of Biological Fungicides for Citrus Production
Since many of the regions where citrus trees grow have warm, humid climates, bacterial and fungal diseases can easily run rampant. Preventative methods are the best way to control diseases in citrus, because if problems occur once new leaves, shoots and fruit are developing, it is likely too late to stop the disease during that growing season. Growers can use …
Post-Freeze Citrus Management
By Muhammad A. Shahid, KeAndre Leaks and Davie M. Kadyampakeni Right after a freeze, you may notice new growth turning black and leaves hardening, yellowing or looking water-soaked. About a week after a severe freeze, leaves may start to curl and turn brown. Leaves and fruits may begin to drop. Do not attempt any recovery treatments immediately after a freeze. …
How To Reduce Spray Drift
The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) provided the following tips for reducing spray drift in citrus groves: Source: UF/IFAS Sponsored ContentGrower Results With ReMedium TI® Mirror Researcher ResultsJanuary 21, 2026Take Advantage of Rising Temperatures to Treat for Fire AntsJuly 1, 2025Take the Sting Out of Fire AntsJune 1, 2025
Florida Citrus Disease Updates
Plant pathologist Megan Dewdney on Nov. 20 presented updates on greasy spot, greasy-green, citrus black spot (CBS) and phytophthora brown rot. Dewdney is a University of Florida Institute of Food and Agricultural Sciences associate professor and Extension specialist at the Citrus Research and Education Center. GREASY SPOT AND GREASY-GREEN Dewdney reported that control measures for greasy spot, caused by the …
Putting Down Brown Rot
By Megan Dewdney Sometimes there is an unfortunate coincidence between the timing of fruit changing color and rain events. This can set up a situation where brown rot occurs unexpectedly and growers need to stop the disease after it has begun. CONTROL OPTIONS By this time of year, the traditional brown rot control measures are less effective. These are primarily …
Proper Site Selection Essential for Phytophthora Prevention
Vulnerability of citrus trees to phytophthora root rot is a concern for cold-hardy growers. But there are precautions that producers can implement that will guard against infection buildup. One of those precautions includes site selection and not planting trees in poorly drained locations, according to Jonathan Oliver, University of Georgia assistant professor and small fruits pathologist. “Site prep is really …
Phytophthora Root Rot a Concern in the Cold-Hardy Region
Phytophthora root rot’s impact on young citrus trees is concerning for groves in the cold-hardy citrus region of North Florida, South Georgia and South Alabama. Newly planted trees are more vulnerable to the disease than older, established trees, says Jonathan Oliver, University of Georgia assistant professor and small fruits pathologist. He discussed the disease’s impact during the Citrus Grower’s Summer …
Syngenta Seeks Summer 2026 Citrus Interns
Syngenta Crop Protection is recruiting citrus interns in Florida for summer 2026. Paid interns will gain hands-on experience in the agriculture industry. Each intern will be assigned to a mentor and a territory for a summer project and be provided a vehicle for work use. Interns will gain experience in territory management along with pest and disease identification. The internships …
Best Practices for Brown Rot Management
By Megan Dewdney The Florida rains have finally come this summer, just in time for early-season fruit to start the maturation process. This means there is some risk of brown rot in early sweet oranges and grapefruit. Much of Florida has been getting summer storms, wetting the soil. While this is excellent in general, the downside is that it allows …
Dealing With Disease: Canker, Black Spot and More
As the rainy season in Florida is set to begin, we caught up with Megan Dewdney to discuss citrus canker and other disease issues. Dewdney is a plant pathologist with the University of Florida Institute of Food and Agricultural Sciences. Q: How has the prevalence of citrus canker been in Florida in the past year or so? A: Dewdney: Citrus …
Developing Snail Management Programs in Florida Citrus
By Lauren Diepenbrock and Nicole Quinn In recent years, a new pest has been added to the ever-evolving scope of pest management in Florida citrus: Bulimulus bonariensis snails. These snails, also referred to as ghost snails or peanut snails, were reported to be clogging irrigation jets in Central Florida in 2020 in limited locations. Now, in 2025, they have spread …
Branch Rot Hits Brazilian Orchards
The disease branch rot is worrying Brazilian citrus growers because of its recent increased occurrence in orchards. Branch rot is also called peduncular rot, branch gummosis or bot gummosis. The main reason for the disease’s occurrence is stress caused to citrus plants by high temperatures, severe periods of drought and attacks from other diseases, such as greening. Fungi of the …
Will Weather Set Florida Free From the Threat of PFD?
By Megan Dewdney Despite being in a transition from a La Niña to a neutral El Niño Southern Oscillation phase, Florida has not had warmer than average temperatures in the last two weeks from March 3. Looking at historical trends, temperatures for the last two weeks of February were in the normal range for this time of year. When looking …
Florida Foliar Disease Outlook for 2025
By Megan Dewdney As I write this article in January 2025, the world is a chilly place, and it is hard to imagine warm and wet weather in Florida. The predicted weather pattern from now until flowering is moving from La Niña toward neutral. This is predicted to bring above-average spring temperatures with reduced rainfall. This is a hopeful sign …
Foliar Disease Watch in Florida
By Megan Dewdney Spring is the time to start thinking about foliar disease management in Florida. Depending on the type of citrus being produced and the market destination, different diseases will be important. POSTBLOOM FRUIT DROP The disease that affects all citrus, particularly oranges, is postbloom fruit drop (PFD). This disease is highly dependent on the weather during bloom. Currently, …
Post-Hurricane Disease Concerns
Phytophthora, citrus black spot and HLB are among diseases that could be spread in Florida groves as a direct or indirect result of Hurricane Milton, researcher Megan Dewdney cautioned. Dewdney, a University of Florida Institute of Food and Agricultural Sciences associate professor of plant pathology, offered suggestions for dealing with those diseases during a recent hurricane recovery webinar. PHYTOPHTHORA Phytophthora …
Protect Against Potential Fungus Post-Hurricane
Citrus growers impacted by Hurricane Helene now must decide the best management strategy to protect trees from potential disease issues prior to harvest. Kim Jones, a citrus grower and packer with operations in Monticello, Florida, and Tifton, Georgia, weighed in on what to consider to protect trees. “Fungus is the biggest risk at this point,” said Jones. “The sunshine is …
Syngenta Seeks Citrus Interns for Summer
Syngenta Crop Protection has announced it is accepting applications for its summer 2025 citrus internship program. These are paid internships offering hands-on experience in the agriculture industry. Applications can be made online. Applicants should complete the survey and upload their resumes here. The deadline for applying is Nov. 8, 2024. ABOUT THE INTERNSHIPS Interns are assigned to mentors and territories …



























