Citrus Canopy Health Is Highly Important for HLB Tolerance

Tacy CalliesHLB Management

By Amit Levy and Tripti Vashisth In Florida, where almost all citrus trees are infected with huanglongbing (HLB), it is important to have an easy and reliable method to check the severity of the disease. Each tree responds differently to Candidatus liberibacter asiaticus (CLas), the bacterial pathogen that causes HLB. Compare it to COVID-19, where some people had the virus …

hlb

First HLB Detection in San Diego County

Len WilcoxCalifornia Corner, HLB Management

The California Department of Food and Agriculture (CDFA) has declared a quarantine in north San Diego County following the detection of the citrus disease huanglongbing (HLB), known as citrus greening. The disease was found in two citrus trees on one residential property in the city of Oceanside. This is the first time the plant disease, which does not harm people …

California

HLB Control Has Been Costly for Growers

Len WilcoxCalifornia Corner, HLB Management

California’s efforts to keep huanglongbing (HLB) at bay have been largely successful. So far, the state’s huge citrus industry has avoided the devastating loss of trees that has occurred in Florida, South America and other commercial citrus-growing regions around the world. However, those efforts have come with a cost to citrus growers. Bruce Babcock, professor of public policy at University …

Brutal Honesty on HLB

Ernie NeffCRDF, HLB Management

Rick Dantzler did not follow normal protocol in providing an update about his organization’s efforts. Dantzler, chief operating officer of the Citrus Research and Development Foundation (CRDF), didn’t talk glowingly about CRDF’s accomplishments. Rather, he started off by telling how far the Florida citrus industry has declined since CRDF was formed in 2009 primarily to find a solution to HLB. …

HLB Practices: Growers’ Attitude Studied

Ernie NeffCalifornia Corner, HLB Management

Although HLB has not yet been detected in a commercial citrus grove in California, growers have been provided with voluntary best management practices to limit the spread of HLB and the psyllids that transmit the disease. A study conducted by researchers at University of California (UC) Davis and UC Riverside, in collaboration with the Citrus Research Board, examined citrus growers’ …

chemicals

Testing Prototypes to Get HLB Therapeutics into Trees

Ashley RobinsonHLB Management, Research

Researchers at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) are working on automated systems that deliver HLB therapeutics into the citrus tree’s phloem, where the materials are most effective. The project, “Development of an automated delivery system for therapeutic materials to treat HLB-infected citrus,” is in its third year. Ozgur Batuman, project director and UF/IFAS citrus …

Citrus Showcase

Keeping HLB out of California Groves

Ernie NeffCalifornia Corner, HLB Management

The recent annual report from California’s Citrus Pest & Disease Prevention Program (CPDPP) offered insights into ways the state’s citrus industry has kept HLB out of commercial groves. Jim Gorden, chair of the group’s Citrus Pest & Disease Prevention Committee, stated that the California industry has “invested countless hours, leveraged millions of dollars and created dozens of innovative partnerships” in …

Florida Grower Advises California on HLB

Ernie NeffHLB Management

Pete Spyke, a Florida gift fruit citrus grower and shipper, recently offered some advice to California citrus growers for dealing with HLB. In a letter to California’s Citrus Pest & Disease Prevention Program, Spyke suggested that growers continue to detect and remove HLB-infected trees. Spyke’s letter follows: Dear California Citrus Growers, Based on my observations and discussions with growers and …

Advances in Therapeutics for HLB Control

Ashley RobinsonHLB Management, Research

The U.S. Department of Agriculture (USDA) is examining different ways to deliver therapeutics to citrus trees for management of citrus greening disease, also know an huanglongbing (HLB). The hope of the USDA initiative is to establish an HLB-therapeutic molecule and identify the most cost-effective strategy to deliver these molecules to growers. The project is in collaboration with the University of …

Technology for Early HLB Diagnosis

Ernie NeffTechnology

Penn State and U.S. Department of Agriculture (USDA) scientists have used cutting-edge CRISPR/Cas technology to develop a diagnostic test that could enable early diagnosis of huanglongbing (HLB). In a study newly published in the journal Phytopathology, the researchers demonstrated that the new test can detect the presence of the HLB causal agent — the bacterium Candidatus Liberibacter asiaticus (CLas) — …

HLB, Lemons and Oranges

Ernie NeffResearch

A group of scientists working in California, New York and Washington has found that Lisbon lemon trees had less of a molecular response than Washington navel orange trees to the pathogen that causes HLB. That pathogen is Candidatus Liberibacter asiaticus (CLas). In part, this might be because leaves of infected lemons tended to accumulate micronutrients, which led to less of …

Dual-Function Peptide Treats and Prevents HLB

Ashley RobinsonHLB Management, Research

New research affirms a unique stable antimicrobial peptide (SAMP) found in an Australian plant can destroy HLB and help prevent infection. Hailing Jin, University of California Riverisde geneticist who led the research, shared the exciting discovery during the 2021 Florida Citrus Show. The naturally occurring peptide is found in HLB-tolerant citrus relatives, such as the Australian finger lime. The peptide …

citrus greening

HLB Slowed by Biocontrol

Ernie NeffHLB Management

Florida citrus growers may have a new tool to help them slow the presence of HLB in already diseased trees, courtesy of researchers at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS). The researchers found that injecting a benign Xylella fastidiosa EB92-1 bacteria biocontrol into infected citrus trees over a period of six years reduced the incidence …

How to Stay HLB-Free in North Florida Groves

Tacy CalliesHLB Management

As temperatures increase across Florida, so does the risk for huanglongbing (HLB) disease, known as citrus greening. While the southern and central portions of the state remain vulnerable to HLB and Asian citrus psyllids (ACP) that spread the disease, growers in North Florida and South Georgia have so far been spared. But Xavier Martini, University of Florida entomologist at the …

Vaccinating Trees Against CTV and HLB

Ernie NeffDiseases

University of Maryland virologist Anne Simon and the company she founded, Silvec Biologics, have successfully vaccinated laboratory hosts against citrus tristeza virus (CTV). They are now focusing on HLB, also called citrus greening. The vaccination induces trees to produce their own therapeutic agents.   Silvec’s vaccination concept is based on the discovery of a novel infectious RNA that the company calls …

Update on Oak Mulch Research to Fight HLB

Ashley RobinsonHLB Management, Research

Researchers have been looking for ways to help Florida citrus growers fight HLB, and spreading oak mulch around the drip line of citrus trees appears promising. Lukas Hallman, a graduate student at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Indian River Research and Education Center (IRREC) is doing research to find what is in oak trees …

Integrated HLB Management in Brazil

Tacy CalliesHLB Management

By Marcelo Pedreira Miranda, Haroldo Xavier Linhares Volpe, Renato Beozzo Bassanezi, Ivaldo Sala and Juliano Ayres Huanglongbing (HLB), or citrus greening, is a notable threat to the citrus industry worldwide and was reported in the central region of São Paulo state (SPS) in Brazil in 2004. HLB then spread quickly throughout SPS, requiring the citrus industry to adapt rapidly to …

HLB Control: A New Potential Method

Ernie NeffHLB Management

A University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researcher has found a material that can be used to silence essential genes within Asian citrus psyllids and in the HLB-causing bacterial pathogen that the psyllids spread. The material is  2’-deoxy-2’-flouro-d-arabinonucleic acid antisense oligonucleotides (FANA ASO), small-sized single-stranded nucleic acids.  The discovery was made by Kirsten Pelz-Stelinski, an associate …

Irrigation and Nutrition Management in the Era of HLB

Ashley RobinsonIrrigation, Nutrition

A solid nutrition and irrigation program can enhance the productivity of HLB-affected trees and improve citrus tree health, potentially making production profitable even under HLB conditions. This was the subject of Davie Kadyampakeni’s talk during a March 9 OJ Break virtual meeting held for citrus growers. Kadyampakeni is a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) assistant …

New Research on HLB-Associated Fruit Drop

Ashley RobinsonFruit Drop

Tripti Vashisth revealed new research information on what causes preharvest fruit drop and possible strategies to mitigate the problem. The Florida citrus industry, stricken by HLB, has suffered a sharp increase in preharvest fruit drop, leading to a substantial reduction in citrus production. According to Vashisth, assistant professor of horticulture at the University of Florida Institute of Food and Agricultural …