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 …
Updating Guidelines for New Plantings
Researchers at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) are taking a whole-systems approach to update current recommendations for new plantings. A research project, “Establishing Healthy Citrus Plantings in the Face of Persistent HLB Pressure,” is led by UF/IFAS entomologist Lauren Diepenbrock. According to Diepenbrock, current guidelines were created pre-HLB and therefore are out of date …
How to Stay HLB-Free in North Florida Groves
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 …
Grower Sees Steady Production Without Chemical Fertilizer
By Owen “Sonny” Conner The two greatest challenges of the last 20 years, for me as a citrus grower, have been HLB and foreign competition depressing prices. Citrus growers had never faced a disease threat even approaching the devastating effects HLB has had on the industry. It was the industry killer we all feared would one day raise its ugly …
IPCs and Tree Performance
Preventing HLB infection in newly planted citrus trees with individual protective covers (IPCs) can improve productivity and fruit quality. Thus far, IPCs have kept young citrus trees free of HLB in research plots. “Once you plant a tree, if it’s not protected, it’s exposed to HLB infection from day one,” says Fernando Alferez, an assistant professor at the University of …
Managing Asian Citrus Psyllid with RNA Interference
Researchers at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) are using RNA interference (RNAi) to alter field populations of the Asian citrus psyllid (ACP). Nabil Killiny, UF/IFAS associate professor, shared the latest findings from his team’s RNAi research in a recent All In For Citrus podcast episode. He says the team is using RNAi to attack …
Update on Oak Mulch Research to Fight HLB
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
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
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 …
Florida Citrus Industry Continues Decline
Florida citrus production has decreased for almost two decades. According to Marisa Zansler, director of economic and market research at the Florida Department of Citrus, the two main factors for the state’s steady decline are citrus greening (huanglongbing, known as HLB) and Hurricane Irma. Zansler presented staggering statistics during the Florida Agricultural Policy Outlook Conference on Feb. 26 that showed …
Citrus Greening Solutions: How Long Will It Take?
It may not be the answer Florida citrus growers want to hear, but it is likely to be several years before a citrus greening remedy is put in place to combat the destructive disease. University of Florida professor Fred Gmitter shared his assessment on possible citrus greening solutions during a recent American Seed Trade Association webinar. “We learn a lot …
Coordinated Treatment Planned for California Citrus
Citrus growers and industry members recently gathered virtually to discuss the Asian citrus psyllid (ACP) and huanglongbing disease (HLB) situation throughout the Central Valley of California. The reason for the concern is a negative trend seen in 2020. ACP DETECTION HISTORYACPs, the vectors for the disease, are widespread in Southern California where HLB-infected trees have been found. There are ongoing …
UF/IFAS VP Scott Angle on HLB Efforts
Florida’s citrus growers are counting on research to help sustain what’s left of an industry decimated by huanglongbing (HLB). The disease remains a focal point of research at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS). Scott Angle, vice president for agriculture and natural resources at UF/IFAS, understands the ramifications if improved HLB management options aren’t available …
Field-Testing Natural Compounds to Fight HLB
Field tests of numerous antibacterial products and plant-derived compounds are underway with the goal of eliminating the HLB-causing bacteria in citrus and reversing plant damage to restore tree health. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) plant root biologist Lorenzo Rossi discusses a new research project funded by the U.S. Department of Agriculture’s (USDA) National Institute of …
California Growers Reminded to Stay Alert
Jim Gorden, chair of the Citrus Pest and Disease Prevention Committee (CPDPC), is greatly concerned about the increase in sporadic Asian citrus psyllid (ACP) detections across California. Gorden sent an open letter to all citrus growers asking them to increase their vigilance against the pest and the risk of citrus greening, known as HLB disease. He said that “While the …
Kaolin Particle Film Reduces HLB Pressure
Researchers found use of kaolin particle film on trees reduced populations of HLB-spreading psyllids and delayed HLB infection. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) assistant professor Christopher Vincent presented his research comparing red and white kaolin particle films with foliar insecticides during a recent UF/IFAS OJ Break webinar. According to Vincent, the particles of kaolin clay …
HLB: The Microbiome’s Role
Researchers Caroline Roper and Nichole Ginnan at the University of California, Riverside led a large research collaboration that sought to explore the microbiome’s role in HLB disease progression. Their recent article in Phytobiomes Journal, “Disease-Induced Microbial Shifts in Citrus Indicate Microbiome-Derived Responses to Huanglongbing,” moves beyond the single-snapshot view of the microbial landscape typical of microbiome research. Their holistic approach …
Time for ACP Dormant Season Sprays
By Lauren Diepenbrock Pest management is an ongoing effort in Florida citrus. Taking advantage of pest life cycles, whether they are tied to the season or plant phenology, can make management efforts have greater impacts on pest populations. For many citrus growers, managing the impacts of Asian citrus psyllid (ACP), the vector of huanglongbing (HLB), is part of the annual …
Flowering Intensity, Shoot Dieback and HLB
Citrus trees grown in Florida continuously undergo various types and levels of stress. Stressors can include severe weather conditions, soil pH, chemicals, pests and diseases. The constant presence of HLB and psyllid infestation adds further stress to the tree, compromising overall tree health. Off-season flowering and prolonged flowering are common responses of trees when undergoing various stress conditions. Off-season and …
Growing Citrus Trees With Oak Mulch
Lukas Hallman, a graduate student at the Indian River Research and Education Center (IRREC), is doing research to find what is in oak trees that apparently helps citrus cope with HLB. The University of Florida Institute of Food and Agricultural Sciences operates the IRREC. “Anecdotal reports from Florida growers claim that citrus trees growing within the drip line of large …



























