Greening and Canker Concerns for Georgia Growers

Jim Rogers Diseases, Georgia

The recent Citrus Growers’ Summer Update in Valdosta, Georgia, provided growers another outlet to learn about two diseases — citrus greening and citrus canker — that could have serious ramifications on the industry’s future in Georgia. Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist, highlighted the seriousness of the discovery of both of the diseases in …

First U.S. Detection of Citrus Yellow Vein Clearing Virus

Jim Rogers California Corner, Diseases

The first detection of citrus yellow vein clearing virus (CYVCV) has been made in Tulare, California. The disease was detected during the California Department of Food and Agriculture’s (CDFA) routine multi-pest survey. The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) has confirmed positive identifications of the disease. CDFA is surveying for the disease in Tulare County …

Citrus Canker Quarantine Established in Alabama

Jim Rogers Diseases, Regulation

Federal and Alabama agriculture authorities recently established a citrus canker quarantine for all of Baldwin County, Alabama, to prevent the spread of the disease. The quarantine was established on July 25 by the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) and the Alabama Department of Agriculture and Industries (ADAI). On June 22, 2021, APHIS confirmed …

Leprosis Management Recommendations for Brazil

Jim Rogers Brazil, Diseases

Fundecitrus recently issued recommendations for leprosis management in Brazil. Leprosis has been expanding in the Brazilian citrus belt for the last six years and is an increasingly significant cause of fruit drop. The disease also causes a reduction in the useful life of the tree, weakened by defoliation and drying of the branches. The main disease management strategy is to …

Sweet Orange Scab Regulations Modified

Jim Rogers Diseases, Regulation

The conditions under which citrus fruit may be moved interstate from areas quarantined for sweet orange scab (SOS) when destined for processing or packing in a commercial citrus-producing state without a statewide SOS quarantine have been modified. The modification was made by the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS). In 2010, APHIS published Federal …

Keep CTV Under Control

Jim Rogers Diseases, Tip of the Week

By Amit Levy Citrus tristeza virus (CTV) infects the citrus phloem. CTV infects almost all citrus varieties, but it causes different disease symptoms depending on the virus isolate, the citrus variety and scion-rootstock combination. Florida has three dominant strains of CTV: T36, a decline-causing strain T30, which normally does not cause severe disease VT, a stem-pitting causing strain CTV is …

Citrus Nutrient Deficiencies? There’s an App for That

Jim Rogers Diseases, Nutrition, Pests, Technology

While sending citrus tissue samples to the lab for analysis remains important, the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) has developed a smartphone application (app) that can supplement lab analysis to identify leaf symptoms of key nutrient deficiencies and certain pests and diseases. Arnold Schumann, a professor of soil and water science with UF/IFAS, demonstrated how …

Don’t Forget Citrus Black Spot in Florida

Jim Rogers Diseases

While HLB tops the agenda, Megan Dewdney, an associate professor of plant pathology and an Extension specialist with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), reminded growers that citrus black spot (CBS) remains a concern. This was the topic of a presentation she made during the Florida Citrus Growers’ Institute held in Avon Park in April. …

Greasy Green Research Approved

Jim Rogers CRDF, Diseases, Research

Due to the initiative of the Indian River Citrus League (IRCL), the Citrus Research and Development Foundation (CRDF) has approved research funding for the greasy green defect on citrus fruit. At a 2021 IRCL board meeting, the issue of greasy green spot was brought up by Tim Sallin of IMG Citrus. Other growers at that meeting also shared their experience …

How to Reduce Bingo Tree Loss to Stem Dieback

Jim Rogers Diseases, Research

By Christopher Vincent, Megan Dewdney and Liliana Cano Bingo mandarin hybrid is a variety with many promising characteristics, but it brings specific challenges to profitable production. One challenge identified early in the push to plant Bingo was stem dieback that led to tree loss. After looking into this problem for the past four years, University of Florida Institute of Food …

Comparison of ACP/HLB Management Tools for Citrus Resets

Jim Rogers Diseases, HLB Management, Research

By Lauren Diepenbrock, Megan Dewdney, Christopher Vincent and Davie Kadyampakeni As the threat of potential shutdowns loomed in March 2020, a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) team put the final plants in the ground, individual protective covers (IPCs) on trees, and kaolin and pesticide applications on a 2.7-acre planting at the Citrus Research and Education …

Fruit Size and Spraying Interval Are Key for Canker Control

Jim Rogers Diseases, Research

The size of fruit that should be sprayed, the spraying interval and ways to avoid copper phytotoxicity were among the citrus canker topics plant pathologist Megan Dewdney offered growers recently. Dewdney said fruit are most susceptible to canker when they are between 3/8 inch and 1.5 inches in diameter. The fruit rind becomes much more resistant when the fruit is …

Citrus Canker Confirmed in South Carolina

Jim Rogers Diseases

The U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of citrus canker disease in a nursery in South Carolina. The nursery sells plants to consumers through online sales. Other nurseries did not receive these plants. Together with state partners, APHIS is working to collect and destroy the plants shipped to consumers in …

Black Core Rot Being Studied

Jim Rogers Diseases, International, Research

A new Hort Innovation project aims to shed some light on how black core rot happens in Australian groves so the citrus industry can learn how to better manage the disease. Black core rot caused by the fungus Alternaria spp. can be a problem for some citrus growers in the southern growing areas in Australia. Citrus infected with Alternaria spp. …

‘Irma Will Haunt Us’ Regarding Citrus Black Spot

Jim Rogers Citrus, Diseases, Weather

Citrus black spot (CBS) disease has only been found in five Southwest Florida counties, but that could change as a result of 2017’s Hurricane Irma, a researcher reiterated recently. University of Florida Institute of Food and Agricultural Sciences plant pathologist Megan Dewdney, in a Feb. 24 presentation, said “Irma will haunt us for a while.” She explained that Irma likely …

Get Canker Before It Gets You

Jim Rogers Diseases, Tip of the Week

By Megan Dewdney Spring is around the corner, and Florida’s first wave of bloom is here. But there is no time to relax and enjoy the flowers because citrus diseases wait for no grower. Young fruitlets become susceptible to canker toward the end of March to the beginning of April. Missing that key window of protection — if the weather …

Sweet Orange Scab and Citrus Canker Movement Conditions Revised

Tacy Callies Diseases, Regulation

The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) has revised the conditions for interstate movement of citrus fruit from areas quarantined for both sweet orange scab (Elsinöe australis, SOS) and citrus canker (Xanthomonas axonopodis, CC). The revisions allow for the movement of fruit to packinghouses located in contiguous states that are not quarantined for either disease. …