Hurricane Irma Raises Black Spot Threat

Ernie Neffblack spot, Diseases

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

HLB

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

scale

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

How Will Irma Affect Citrus Canker Management?

Tacy CalliesDiseases

By Evan G. Johnson The citrus canker season is quickly approaching again, so it is time to start planning your canker management program to avoid fruit drop and fresh-market quality loss. It is easy to forget the importance of controlling citrus canker with the current state of HLB in Florida. However, citrus canker can cause almost complete crop loss if … Read More

Outlook for Postbloom Fruit Drop

Tacy CalliesDiseases

By Megan M. Dewdney, Tripti Vashisth and Ariel Singerman In 2017, the damage from postbloom fruit drop (PFD) was lower than the previous three years. This was mainly due to the low rainfall accumulation in late winter and early spring. The long bloom with relatively few flowers at any one time made the decision of when to apply a fungicide … Read More

Robots May Soon Detect Grove Pests and Diseases

Ernie NeffDiseases, Pests, Technology

pests

It may not be long before a grower sips coffee and works on the computer while a robot roams the grove checking for HLB-spreading psyllids and other pests and diseases. That’s thanks to machine vision software. University of Florida Institute of Food and Agricultural Sciences scientist Arnold Schumann tells about research he has been conducting. Schumann says researchers have developed … Read More

Managing Disease with Copper and IPM

Ernie NeffDiseases

disease

Integrated pest management (IPM) strategies and copper are both good control measures for common citrus foliar fungal diseases, as well as for citrus canker. So says University of Florida Institute of Food and Agricultural Sciences plant pathologist Ozgur Batuman. Batuman summarizes information he presented at a fall field day and seminar attended by about 60 people at the Southwest Florida … Read More

Sweet Orange Scab Detected in Alabama

Tacy CalliesDiseases

U.S. Department of Agriculture (USDA) officials have confirmed the first detection of sweet orange scab (SOS) in Alabama. The fruit sample was collected in Baldwin County by Alabama Department of Agriculture and Industries’ (ADAI) plant protection inspectors during a delimiting survey for citrus greening disease. The Auburn University Plant Diagnostic Clinic provided the initial diagnosis of SOS, and USDA Animal … Read More

What Lies Ahead for Florida Citrus?

Tacy CalliesDiseases, HLB Management, Pests, Varieties

Editor’s note: This article is part of the special coverage on the 100th Anniversary of the UF/IFAS Citrus Research and Education Center, found in the October 2017 issue of Citrus Industry magazine. By Tom Nordlie Although it’s difficult to predict future events, directors of the University of Florida Institute of Food and Agricultural Sciences Citrus Research and Education Center (CREC) … Read More

Current Challenges to Florida Citrus

Tacy CalliesCitrus Greening, Diseases

Editor’s Note: This article was written before Hurricane Irma made landfall in Florida and damaged the state’s citrus industry. This article is part of the special 100th anniversary coverage of the Citrus Research and Education Center, found in the October 2017 issue of Citrus Industry magazine. By Tom Nordlie What are the current challenges to Florida’s citrus industry? To a … Read More

Citrus Leprosis: a Continuing Threat in Florida and North America

Tacy CalliesDiseases

By Richard F. Lee The old-timers called citrus leprosis “nailhead rust.” Prevalent in Florida in the early 1900s, the disease was first called leprosis in the 1920s by H.S. Fawcett. Although the disease was widespread in Florida at one time, it mysteriously disappeared in the mid-1960s. L.C. Knorr [University of Florida/Institute of Food and Agricultural Sciences Citrus Research and Education … Read More

Citrus Canker Management for 2017

Kelsey FryDiseases

By Evan Johnson The citrus canker season is quickly approaching again, so it is time to start preparing your canker management plan. It is easy to forget the importance of controlling citrus canker with the current state of HLB in Florida. However, citrus canker can cause almost complete crop loss if environmental conditions are favorable for disease early in the … Read More

Buddha’s Hand Citron Could Play Role in Canker Resistance Breeding

Kelsey FryCitrus, Diseases

By Naveen Kumar, R.C. Ebel and P.D. Roberts Citrus canker became endemic in Florida after several introductions and eradication programs dating back to 1915. The citrus industry struggles for an effective, permanent program. Canker is an expensive disease due to the need to increase the number of sprays and products applied. Canker also causes enormous economic losses due to fruit … Read More

Researcher Provides Leprosis Update

Ernie NeffDiseases, Research

leprosis

The citrus viral disease leprosis, found briefly in Florida in the 1960s, is now in South America, Central America and Mexico. Ron Brlansky, University of Florida professor emeritus, provided an update on the disease at a March OJ Break in Lake Alfred. “It (leprosis) causes fruit spotting, leaf spots, leaf drop, fruit drop and even some major twig dieback of … Read More