Nursery Diseases at Planting: What to Watch for

Tacy CalliesDiseases, nursery

By Ozgur Batuman and Megan Dewdney Citrus nurseries work very hard and put forth considerable effort to reduce pest and disease problems. However, there continues to be problems with certain diseases, because the nursery environment for growing citrus trees is ideal for many pests and diseases. Basic principles of good nursery sanitation practices together with screening and removing suspected or … Read More

Citrus Canker Management Through the Year

Ernie NeffDiseases

Plant pathologist Megan Dewdney with the University of Florida Institute of Food and Agricultural Sciences offers suggestions for managing citrus canker at different times of the year. She is an associate professor at the Citrus Research and Education Center (CREC) in Lake Alfred. Dewdney suggests that copper sprays begin when fruit reach three-eighths of an inch in diameter in groves … Read More

Algal Spot: A Re-emerging Disease

Tacy CalliesDiseases

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 … Read More

Citrus Leprosis Poses a Threat to Florida

Tacy CalliesDiseases

By Amit Levy, Ozgur Batuman, Peggy Sieburth and Lauren Diepenbrock Citrus leprosis is an exotic viral disease not currently present in Florida. This disease is of interest since it was reported in citrus in Florida and Brazil in the early 1900s, where it caused great crop and tree losses, but it was eliminated from Florida in the early 1960s. Currently, … Read More

Planning for Foliar Disease Management in 2020

Tacy CalliesDiseases

By Megan Dewdney and Evan Johnson In 2019, the trend of fewer problems with foliar fungal diseases for Florida citrus continued, which was good news for the industry. Despite the El Niño conditions during the spring, little postbloom fruit drop (PFD) was observed because the temperatures were low (< 75 F) when it rained during bloom. The southern parts of … Read More

Homeowners Oppose Stay in Citrus Tree Battle

Daniel CooperDiseases, Legislative

budget

(NSF) — Attorneys for Lee County homeowners urged the Florida Supreme Court on Monday to reject the state’s request for a stay in a long-running legal battle about compensating residents for healthy citrus trees cut down amid an effort to halt the spread of citrus canker disease. The Florida Department of Agriculture and Consumer Services last week asked the Supreme Court to put the … Read More

Citrus Black Spot Quarantine Area Updated in Florida

Daniel CooperDiseases, Industry News Release

aphis

Effective immediately, the Animal and Plant Health Inspection Service (APHIS) is adding eight sections in Charlotte County, nine sections in Lee County, 28 sections in Hendry County, and five sections in Collier County to the citrus black spot (CBS) quarantine area in Florida. This action is in response to the confirmation of CBS during annual surveys conducted by APHIS and … Read More

FDOC Response to Cancer Study

Daniel CooperCitrus, Diseases, Industry News Release, Research

orange juice

A new study suggesting a link between sugary drink consumption, including 100% fruit juice, and increased cancer risk was recently published in a medical journal. The study has spurred a series of news media stories. Researchers of the study, who are based in France, assessed the associations between the consumption of sugary drinks (sugar sweetened beverages and 100% fruit juices), … Read More

Studying Citrus Greening with an Integrated Approach

Daniel CooperCitrus Greening, Diseases, HLB Management, Industry News Release, Psyllids, Research

citrus greening

While citrus growers continue to look for best management approaches to deal with the deadly greening disease, scientists will take an integrated look at how to protect young trees by using existing tools growers can use. Five scientists from the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) will compare insect management tools, including insect-proof netting. Researchers also … Read More

An Important Reminder on Citrus Tristeza Virus

Tacy CalliesDiseases

By Amit Levy and Ozgur Batuman Citrus tristeza virus (CTV) is an important citrus pathogen that, in the past, had a dramatic effect on the citrus industry and caused the loss of almost 100 million trees worldwide. These trees were propagated on sour orange rootstock. The disease created a need for tristeza-tolerant rootstocks to sustain the citrus industry, because only … Read More

Citrus Black Spot Update

Ernie Neffblack spot, Diseases

Callie Walker with the Florida Department of Agriculture and Consumer Services (FDACS) recently gave an update on the citrus black spot quarantine in Southwest Florida. Walker is bureau chief of pest eradication and control for FDACS’ Division of Plant Industry and serves as statewide director for the Citrus Health Response Program. She summarizes the presentation she made at the Florida … Read More

Hurricane Irma Raises Black Spot Threat

Ernie Neffblack spot, Diseases

aphis

University of Florida Institute of Food and Agricultural Sciences Extension pathologist and associate professor Megan Dewdney reported that U.S. Department of Agriculture (USDA) scientist Tim Gottwald thinks there’s a “fairly high” chance that Hurricane Irma spread citrus black spot. Black spot had been confined primarily to Southwest Florida, especially Collier and Hendry counties, before Irma hit the state with damaging … Read More

Phytophthora: An Old Problem with New Challenges

Tacy CalliesDiseases

By Evan Johnson Diseases caused by phytophthora continually threaten Florida citrus production. Brown rot can directly reduce yields of early maturing varieties including Hamlin and grapefruit, can delay harvest of fresh market fruit until infected fruit have dropped, or risk packinghouse rejection of the load because it can spread post-harvest. Foot and crown rot can kill trees but are uncommon … Read More

Fungal Foliar Disease Concerns for 2019

Tacy CalliesDiseases

By Megan Dewdney The Florida citrus-growing seasons of 2017 and 2018 were quiet in terms of fungal foliar disease outbreaks. Small pockets of severe disease occurred sporadically, but there were no widespread reports of diseases like postbloom fruit drop, much to the relief of the industry. Greasy spot has flared up in a few locations on cultivars like Valencia, and … Read More

Brown Rot Basics

Ernie NeffDiseases

PFD

Plant pathologist Megan Dewdney with the University of Florida Institute of Food and Agricultural Sciences discussed the basics of brown rot and its control at a recent disease seminar in Immokalee. Approximately 60 growers and others attended the seminar held at the Southwest Florida Research and Education Center. Brown rot is especially prevalent in early-season citrus varieties. “It’s particularly problematic … Read More

Lake Wales Grower Discusses Foot Rot and PFD

Ernie NeffDiseases, PFD

PFD

Lake Wales citrus grower Frank Thullbery, 88, says groves in his area have suffered badly from foot rot, or phytophthora, in recent years. He has also struggled with postbloom fruit drop (PFD). “I’ve seen half of the groves gone bad from foot rot, and a lot of people are not replacing their trees when they pull them out,” Thullbery says. … Read More

California Industry Updates Presented at Spring Citrus Meeting

Daniel CooperCitrus Greening, Diseases

By Brian German The Spring Citrus Meeting held last week in Tulare County touched on several major issues growers are concerned with, and included presentations on best practices for managing citrus trees. The day began with important information related to Asian citrus psyllid (ACP) and the disease it causes, huanglongbing (HLB), which has been growing at an alarming rate in … Read More

Homeowners to Receive Compensation After 17-Year Canker Battle

Abbey TaylorDiseases, financial

A legal fight over citrus canker has finally come to a close after 17 years. Citrus canker, which reappeared in Florida in 1986, is a bacterial disease that can cause blemishes on the fruit, and in some cases, can cause fruit to drop prematurely. Canker is usually spread by the wind, making it difficult to control. In 2000, Florida was … Read More

California Researchers Work Toward Early HLB Detection

Abbey TaylorCitrus Greening, Diseases, HLB Management

hlb

Although the Florida and California citrus industries may differ, they are both vulnerable to citrus greening disease. The brightest minds from both states are working to detect, manage and control this devastating disease. Most recently, University of California researchers have been working to find methods for early detection of huanglongbing (HLB), or citrus greening disease. AgNet West’s Taylor Hillman has … Read More