quarantine

New HLB Quarantine Area for California

Daniel CooperCalifornia Corner, HLB Management, Regulation

A newly established quarantine area has been declared following the detection of HLB in five trees in the Valley Center area of California’s San Diego County. The trees were located on a residential property with non-commercial citrus acreage. This is the first time the disease has been confirmed in Valley Center, marking the third area in San Diego County to …

HLB-affected

Root Nutrient and Fertilization Guidelines for HLB-Affected Trees

Daniel CooperNutrition, Tip of the Week

By Davie Kadyampakeni, Lorenzo Rossi and Alan Wright  Huanglongbing (HLB) disease lowers tree performance by reducing water and nutrient uptake as a result of root loss. HLB-affected trees have a fibrous root loss of about 30% to 80%, which increases as disease symptoms develop in the canopy. Investigating optimal nutrient concentrations in citrus roots thus improves the understanding of HLB …

HLB Treatments ‘A Mixed Bag of Results’

Josh McGillHLB Management

A variety of treatments Florida citrus growers are using for HLB have so far produced mixed results, according to observations reported by Highlands County Citrus Growers Association (HCCGA) President Aaron Nelson. In a recent association newsletter, Nelson wrote that many are anxious to see harvest data showing what effects the treatments have had over the past year. The treatments he …

Trekking Toward HLB-Resistant Trees

Josh McGillBreeding, HLB Management, Research

By Michael Rogers Much has been discussed recently about the promise and potential of utilizing CRISPR technology to create HLB-resistant trees for Florida’s citrus growers. The primary objective in citrus gene editing is to develop new varieties that are resistant to HLB disease while remaining non-transgenic. To achieve this goal, researchers make alterations to or eliminate specific genes within the …

Field Day Showcases Efforts to Breed HLB-Tolerant Oranges

Josh McGillBreeding, Events

By Maegan Beatty On Oct. 27, Jose Chaparro hosted a citrus breeding research update at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Teaching Orchard in Gainesville. The event included a variety display and field tour. Chaparro, a UF/IFAS associate professor of horticultural sciences, focused on how he and his team are taking on the significant task …

$5 Million Awarded to UF/IFAS for HLB Research

Josh McGillHLB Management, Research

The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) has been awarded five federal grants totaling more than $5 million to control HLB. The grants are from the U.S. Department of Agriculture’s National Institute of Food and Agriculture (NIFA).   HLB is caused by the bacterium Candidatus Liberibacter asiaticus (CLas). The Asian citrus psyllid can transmit CLas into a …

HLB Resources for California Growers

Josh McGillCalifornia Corner, HLB Management

Recently, the California Department of Food and Agriculture (CDFA) declared an HLB quarantine in Ventura County following the first detections of the disease in the county. In response, the Citrus Pest & Disease Prevention Program (CPDPP) issued a list of HLB resources. The resources are intended to help inform the citrus industry about what changes to expect from the quarantine, …

Universities Receive 11 Federal Grants for HLB Research

Josh McGillHLB Management, Research

The U.S. Department of Agriculture’s National Institute of Food and Agriculture (USDA NIFA) has invested more than $25 million in 11 projects as part of the Emergency Citrus Disease Research & Extension program. This program brings the nation’s top scientists together with citrus industry representatives to find scientifically sound solutions that combat and prevent citrus greening (HLB)​ at the farm level. Some of this …

Research Update on Oxytetracycline Injection for HLB Management

Josh McGillHLB Management, Research

By Ute Albrecht The German scientist Paul Ehrlich pioneered the research for “magic bullets” — chemicals that could kill a microorganism but did not harm the patient. He also coined the term “chemotherapy” and paved the way for developing synthetic drugs. The first synthetic antibiotic (the first sulfa-type antibiotic) to successfully treat human bacterial diseases without major side effects was …

First HLB Detection in Ventura County

Tacy CalliesCalifornia Corner, HLB Management, Regulation

The California Department of Food and Agriculture (CDFA) has declared a quarantine in Ventura County following the detection of the citrus disease huanglongbing (HLB), or citrus greening, in two citrus trees on one residential property in the city of Santa Paula. These detections are the first HLB-positive trees in Ventura County. CDFA is working with the U.S. Department of Agriculture …

Treat HLB Trees With the Right PGR at the Right Time

Josh McGillHLB Management, PGRs, Research

By Tripti Vashisth, Wesley Webb and Taylor Livingston As trees become symptomatic for HLB, leaves experience an imbalance of plant hormones. This hormonal imbalance exacerbates HLB symptoms and can lead to more stem dieback, poor vegetative growth and fruit drop. This ultimately leads to reduced bearing wood, resulting in yield losses and tree decline. Thus, the use of growth-promoting hormones …

HLB Tools for Today and Tomorrow

Josh McGillCitrus Expo, HLB Management

By Frank Giles and Tacy Callies The Citrus & Specialty Crop Expo hosted two citrus educational sessions during the Aug. 16–17 event held at the Florida State Fairgrounds in Tampa. The sessions included both long-term research aimed at delivering trees resistant to HLB as well as what growers can do today to help mitigate the effects of the disease in …

Gene Confers Resistance to HLB and Citrus Canker

Josh McGillHLB Management, International, Research

In August, Horticulture Research published a paper titled An endolysin gene from Candidatus Liberibacter asiaticus confers dual resistance to huanglongbing and citrus canker. Researchers found that an endolysin encoded by the Candidatus Liberibacter asiaticus (CLas) prophage has dual resistance to huanglongbing (HLB) and citrus canker. A prophage is the genetic material of a bacteriophage, and a bacteriophage is a virus …

Transgenic Efforts Against HLB

Josh McGillBreeding, HLB Management, Research

Matthew Mattia recently provided an overview of work at the U.S. Department of Agriculture Agricultural Research Service (USDA ARS) transgenic test site in Fort Pierce. Transgenic refers to an organism that contains genetic material into which DNA from an unrelated organism has been artificially introduced. Scientists at the Picos Farm screen transgenics for suppression of citrus Candidatus Liberibacter asiaticus (CLas), …

HLB Treatment Approved in Florida

Josh McGillHLB Management, Industry News Release

Invaio Sciences in late August announced that its Trecise technology to deliver ArborBiotic for the suppression of HLB in oranges received approval from the Florida Department of Agriculture and Consumer Services. The approval came under section 24(c) of the Federal Insecticide, Fungicide and Rodenticide Act.    Invaio stated that the product’s closed-system design does not require drilling. Unlike conventional injection treatments, …

Agrobacteria Shows Promise Against HLB

Josh McGillHLB Management, Research

U.S. Department of Agriculture Agricultural Research Service (USDA ARS) scientists have discovered a way to augment a citrus tree’s natural resistance to pathogens, including HLB. The scientists are in the Crop Improvement and Genetics Research (CIGR) unit in Albany, California. According to James Thomson, a geneticist at CIGR, by incorporating receptors that can recognize pathogens, scientists are able to activate …

Fundecitrus Researchers Honored for HLB Article

Josh McGillAwards, Brazil, HLB Management

Six Fundecitrus researchers recently received an award from the journal Tropical Plant Pathology, edited by the Brazilian Society of Phytopathology. The award is in recognition of the researchers’ work in the scientific article “Overview of citrus huanglongbing spread and management strategies in Brazil.” The researchers honored are Renato Beozzo Bassanezi, Sílvio Aparecido Lopes, Marcelo Pedreira de Miranda, Nelson Arno Wulff, …

Connecting Research for Better HLB Management Results

Josh McGillHLB Management, Research, Tip of the Week

By Megan Dewdney To make informed management decisions, growers need to know about and understand the findings from huanglongbing (HLB) research that are currently available. However, the delivery of research results to growers is often fragmented, and results can be difficult to find. Furthermore, what information and conclusions are available to growers from projects or scientific journals can be highly …

Hairy Approach May Get to the Root of HLB

Josh McGillHLB Management, Research, Texas

Developing disease-resistant, high-quality improved crop varieties may seem like a “hairy” task, but Texas A&M AgriLife Research scientists may have gotten to the root of the issue. A new biological technology that develops and multiplies disease-resistant citrus plants is under development by an AgriLife Research team led by Kranthi Mandadi. Mandadi is an associate professor at the Texas A&M AgriLife Research …

CRDF Board Focused on HLB Treatments

Josh McGillCRDF, HLB Management, Research

The Citrus Research and Development Foundation (CRDF) board of directors meeting in July focused largely on the use of oxytetracycline (OTC) as an HLB treatment in citrus. The board considered projects testing it in combination with other antimicrobial compounds or as a standalone treatment. Trunk injection of OTC has given the Florida citrus industry hope that it might be a …