Entomologist Kirsten Pelz-Stelinski recently shared findings from trials on the use of foliar-applied and trunk-injected antibiotics for controlling HLB and the Asian citrus psyllids (ACP) that spread the disease. Pelz-Stelinski is associate center director at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center (CREC) in Lake Alfred. In a May 17 presentation …
HLB in Florida Is a Warning to California
The damage that HLB has inflicted on Florida citrus groves and production over the past 18 years should serve as a warning for California producers, California’s Citrus Pest & Disease Prevention Program (CPDPP) stated recently. CPDPP noted that with HLB detected in thousands of California residential trees, it’s important for commercial growers to take steps to prevent the disease. According …
Repurposing Tools to Tackle HLB
By J. Scott Angle, jangle@ufl.edu, @IFAS_VP The hurricane-battered harvest numbers don’t show it, but we’re in a much better place in developing scientific solutions for managing HLB than we were a year ago. That’s because our scientists have discovered that tools invented to solve other problems can help address your one big problem. GIBBERELLIC ACIDFor example, gibberellic acid (GA) has …
Awareness Campaign Battles HLB in Brazil
Brazil’s Fundecitrus in 2022 and 2023 conducted an awareness campaign to replace citrus and myrtle plants to combat HLB in the municipality of Itobi, São Paulo. The citrus and myrtle plants were replaced with other fruit and ornamental species that do not host the Asian citrus psyllid that transmits HLB, also known as greening disease. These citrus and myrtle plants …
Native Lime Might Keep HLB Out of Australia
A comprehensive map of the genome of an Australian native lime species that is resistant to HLB could be the key to preventing the disease from entering Australia. Researchers from The University of Queensland (UQ) in Australia have sequenced the genome of the Australian round lime, also known as the Gympie lime. They are now looking at five other native …
Project Seeks Quick HLB Diagnostic Tests
Canadian college Seneca, in partnership with Ottawa-based Evik Diagnostic Innovations Inc., is working to develop a quick diagnostic test for the citrus disease HLB. Frank Merante, professor in Seneca’s School of Biological Sciences & Applied Chemistry, is the principal investigator for the project. The idea behind the research was to develop a simple way for growers to test crops and identify the …
Update on HLB-Tolerant/Resistant Tree Programs
The Florida Citrus Commission (FCC) in March heard updates on programs intended to provide growers with HLB-tolerant or -resistant trees and on other Florida Department of Citrus (FDOC) scientific research programs. Director of Scientific Research Rosa Walsh provided the updates. The FCC serves as the FDOC’s governing board. Walsh announced that for the FDOC’s Program for Expedited Propagation, all materials …
Lessons Learned From HLB as an Immune-Mediated Plant Disease
By Nian Wang How the huanglongbing (HLB) pathogen Candidatus Liberibacter asiaticus (CLas) causes damage to infected citrus trees has been widely debated. A recent study demonstrates that HLB is an immune-mediated plant disease (Ma et al., 2022). It was discovered that CLas infection of citrus stimulates systemic and chronic immune response in phloem tissues, including reactive oxygen species (ROS) production, …
Deficit Irrigation in HLB-affected Citrus Trees
By Davie Kadyampakeni, Samuel Kwakye, Hossein Ghoveisi, Lauren Diepenbrock and Jawwad Qureshi Deficit irrigation practices can reduce water and energy costs, thus potentially increasing water-use efficiency and water savings in citrus production. Irrigation management through deficit applications, if timed at periods of reduced water demand, could help trigger increased root water and nutrient uptake while synchronizing citrus flush patterns. These …
Uruguay Has First HLB Detections
The first cases of plants with HLB disease have been confirmed in Uruguay, according to a health emergency note released by the country’s Ministry of Livestock, Agriculture and Fisheries. Plants with symptoms were found in a residence in the city of Bella Unión. After laboratory analysis, the presence of the disease was confirmed. Inspections were carried out in the homes …
CRDF Funds Project to Arrest HLB Bacteria
At the latest Citrus Research and Development Foundation (CRDF) board of directors meeting, funding was approved for a project by Robert Turgeon. He is a professor of plant biology at Cornell University. “Dr. Turgeon is considered by some to be the world’s foremost expert on phloem physiology. If his project succeeds, it could solve our problem with HLB,” CRDF chief …
HLB Concerns Government Officials in Brazil
Brazil’s Fundecitrus on Feb. 15 participated in a meeting with state and local government representatives to discuss the country’s citrus greening (HLB) situation. Representatives of the Department of Agriculture and Supply (SAA) of the state of São Paulo and mayors of some municipalities in the citrus belt also attended. Mayors and representatives of city halls expressed concern about the economic …
Why There Is a Lack of HLB in Georgia
HLB has yet to become a major problem for Georgia’s citrus producers. Jonathan Oliver, University of Georgia assistant professor and small fruits pathologist, attributes the disease’s lack of presence in Georgia’s commercial groves to multiple factors. “It still comes down to the fact that, number one, you don’t see symptoms for a while. A lot of our trees are young,” …
Rectify Injection Available for HLB in Florida
Rectify, AgroSource, Inc.’s 95% oxytetracycline hydrochloride-based tree-injection product, is expected to be available for use against HLB in Florida citrus as early as Feb. 24. The product will be available to growers through existing commercial agricultural product distributors. AgroSource petitioned and received a Special Local Needs (SLN) approval for Rectify by the Florida Department of Agriculture and Consumer Services (FDACS) …
First HLB Confirmation in City of San Diego
The citrus disease HLB has been confirmed for the first time in the city of San Diego, California, making it the second city in San Diego County with a positive detection. (Read about the first San Diego County detection here.) The new detection was made in a residential citrus tree located in the Rancho Bernardo area of the city. The …
OLL Sweet Oranges Producing Pre-HLB Fruit Quality
By Jude Grosser, Fred Gmitter and Maria Brenelli The new OLL (Orie and Louise Lee) series of sweet oranges (OLL-4, OLL-8 and OLL-20) are very high-quality processing sweet oranges that generally produce higher soluble solids and better juice color than Valencia. OLL trees are more vigorous than Valencia, and anecdotal evidence suggests they are slightly more HLB-tolerant than Valencia. Trees …
Trialing Tree Immunizations for HLB, Xylella
Australia’s Hort Innovation has announced an $8.7 million investment to trial tree immunizations that protect Australia’s horticulture industries against the deadly huanglongbing (HLB) and Xylella diseases (including citrus variegated chlorosis). Hort Innovation is a grower-owned, not-for-profit research and development corporation for Australia’s horticulture industry. Hort Innovation Chief Executive Brett Fifield said the investment aims to safeguard key Australian horticulture industries by …
Natural Compounds Might Fight HLB
The U.S. Department of Agriculture (USDA) has awarded Florida International University (FIU) scientists $500,000 to investigate natural compounds that could suppress or even eliminate the bacteria that causes HLB. FIU Institute of Environment researcher Kateel Shetty is leading the search for an antimicrobial compound that could help citrus growers. The FIU team’s theory is that if they can identify a …
Psyllids and HLB in Georgia Citrus
When commercial citrus acreage started migrating north some years ago, the big question was: To what extent would Asian citrus psyllids (ACP) and HLB migrate with the crop? With citrus getting well established in South Georgia, the pest and disease are there, but not yet at devastating levels like in Florida. Johnathan Oliver, an assistant professor of fruit pathology with …
Trunk Injection for HLB: What You Need to Know
Some Florida citrus growers have recently started oxytetracycline hydrochloride (OTC-HCl) injection into tree trunks to help manage HLB. Other growers are considering it. Researcher Ute Albrecht offered a list of best practices for the product’s use during a Jan. 31 presentation in Immokalee. The presentation was made at the University of Florida Institute of Food and Agricultural Sciences Southwest Florida …