The title of Megan Dewdney’s Citrus Expo presentation was, “Shorten the skirts? Whether skirting improves citrus black spot fungicidal management.” The answer was “no,” based on trials she conducted to make that determination. But while skirting doesn’t appear to improve citrus black spot (CBS) fungicide programs, she pointed out that “there are other good disease management reasons to skirt.” Dewdney …
Florida Black Spot Quarantine Expands
The citrus black spot (CBS) quarantine in Florida was recently expanded in five Southwest Florida counties by the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS). APHIS added 37 sections in Charlotte County, 17 sections in Collier County, 45 sections in Glades County, 68 sections in Hendry County and 28 sections in Lee County to the quarantine …
What To Do About Algal Spot
By Megan Dewdney I did not need to visit my field trial to know that algal spot was in bloom on citrus in the last month. I have received many phone calls about it recently as growers notice the bright orange doughnuts on their tree limbs. For those unfamiliar with algal spot, it is a disease that occurs mostly on …
California Reports Two Citrus Pests
The Citrus Pest & Disease Prevention Program in California recently detected sweet orange scab (SOS) in new areas of the state. Additionally, an unofficial lime swallowtail butterfly (LSB) sample was identified from Los Angeles County, and several LSB sightings have been reported in Los Angeles and San Luis Obispo counties. SWEET ORANGE SCABSOS is a cosmetic fungal disease that impacts …
Renewed Effort to Stop Chinese Citrus Imports
U.S. Senators Marco Rubio and Rick Scott of Florida recently urged U.S. Secretary of Agriculture Tom Vilsack to re-implement a prohibition on the importation of five varieties of citrus from China. The U.S. Department of Agriculture (USDA) in April 2020 decided to allow the importation of the Chinese varieties. “The USDA’s decision continues to risk an increase in unfair trade competition …
App Now Available to Diagnose Citrus Leaf Problems
Visual identification of nutrient deficiencies and leaf damage is an important diagnostic tool for fine-tuning management of citrus. Arnold Schumann, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) professor, shared how UF/IFAS researchers have used artificial intelligence (AI) to diagnose citrus nutritional deficiencies, diseases and pest damage. According to Schumann, disease and pest symptoms on leaves may cause …
Sneak Peek: February 2021 Citrus Industry
While everyone strives to protect themselves from coronavirus disease, growers have an additional concern: protecting their trees from citrus disease. While HLB is of course the most damaging disease of citrus, there are other diseases that should not be overlooked. Disease management is the theme of the February 2021 issue of Citrus Industry magazine. University of Florida Institute of Food …
Update on CRISPR Research for Citrus Improvement
By Nian Wang, Fred Gmitter and Manjul Dutt Nearly all commercially important citrus types — oranges, grapefruits etc. — have originated by mutations that have accumulated over several hundreds to thousands of years, from what once was an original, individual sweet orange tree and a single grapefruit tree. The many different cultivars that we know today are descended from those …
Sending Fresh Citrus out of Florida
By Mark A. Ritenour The holiday season is a busy time for sending friends and family thoughtful gifts. For Floridians, the abundance of fresh produce during the winter months motivates many to share the experience with others. This is especially true for fresh citrus. Florida’s citrus gift fruit shippers have been supplying such treats for decades. With COVID-19 and a …
Black Spot Likely in More Florida Counties
Although citrus black spot has only been detected in commercial groves in five Southwest Florida counties, it is still spreading and likely to be in additional counties, according to plant pathologist Megan Dewdney. The five counties with detections are Charlotte, Collier, Glades, Hendry and Lee. Dewdney is a University of Florida Institute of Food and Agricultural Sciences associate professor at …
South African Citrus Exports to Set Record
South African citrus exports, both globally and to the United States, are expected to reach record levels in 2020, according to a report from the U.S. Department of Agriculture’s Foreign Agricultural Service (USDA/FAS). The expected record is based on the pace of exports up to August 2020, increased production, a spike in demand for health reasons and limited logistics disruptions …
Phosphite Best for Algal Spot
Algal spot had rarely been seen in Florida groves until fairly recently, Megan Dewdney reported in a virtual Florida Citrus Growers’ Institute presentation. The University of Florida Institute of Food and Agricultural Sciences plant pathologist said she started hearing from concerned orange growers within the past five years. Those growers told her that copper, the historical recommendation for the disease, …
Black Spot and Production Guide Updates
Megan Dewdney recently provided information about positive results from fungicide trials for citrus black spot, as well changes to the new Citrus Production Guide. Dewdney is a plant pathologist with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), working at the Citrus Research and Education Center. Dewdney conducted the fungicide trials for black spot in a 20-year-old …
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 …
All In For Citrus Podcast, September 2020
National recognition, new findings on black spot control, and research on antimicrobial peptides highlight the September episode of the All In For Citrus podcast. Citrus Research and Education Center Director Michael Rogers starts the episode with the announcement that the University of Florida was ranked in the top 10 of U.S. News and World Report’s Top Public Schools list. Rogers …
The Future Faces of Florida Citrus
Meet the four students who received the FMC Citrus Ag Production Scholarships. By Tacy Callies The FMC Citrus Ag Production Scholarships (CAPS) program, a partnership between AgNet Media and FMC, was created to support Florida citrus production and encourage interested youth to pursue careers in citrus. Two University of Florida students and two Florida Southern College students each were awarded …
APHIS Annual Report Highlights Citrus Efforts
The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) recently released an annual report titled “Plant Protection and Quarantine: Helping U.S. Agriculture Thrive — Across the Country and Around the World.” The document includes updates on efforts to manage citrus diseases. “PPQ (Plant Protection and Quarantine) stands shoulder-to-shoulder with citrus growers to combat citrus canker, huanglongbing (HLB …
Algal Spot: A Re-emerging Disease
By Megan M. Dewdney Algal spot has not been seen frequently for many years, but in the last few years I have been getting more questions about identification and management. The disease is caused by a green alga, Cephaleuros virescens. The alga is not considered a parasite, as it grows superficially, but it does cause damage to trees if left …
Black Spot Scouting and Control
“The most important time to scout for black spot is when the fruit begin to change color,” said University of Florida Institute of Food and Agricultural Sciences plant pathologist Megan Dewdney. She has seen color change for Valencia oranges, the most commonly infected variety, from December to March. But she added it is usually late-February to early-March when citrus black …
Sneak Peek: February 2020 Citrus Industry Magazine
The February issue of Citrus Industry magazine lets growers know what diseases to be on the lookout for this season and how best to spot them in the grove. University of Florida (UF) researchers Megan Dewdney and Evan Johnson give citrus growers tips on planning for disease management in 2020 in their article. Citrus canker, greasy spot, melanose, black spot …