Mulch Suppresses Psyllids in Young Trees 

Tacy Callies Psyllids, Tip of the Week

By Jawwad A. Qureshi, Lauren Diepenbrock and Davie Kadyampakeni  Protecting citrus trees from the Asian citrus psyllid (ACP) is critical to reducing the spread and severity of huanglongbing (HLB) disease. The frequent availability of viable shoots in young trees is attractive to psyllid colonization, feeding and oviposition events. UV-metalized reflective mulches reflect ultraviolet light, which is disturbing for some insects …

Florida Citrus: The Road Back

Tacy Callies Economics, Florida

By Tom Spreen The Florida citrus industry has experienced a difficult stretch of years since the record crop year of 2003–04, when over 240 million 90-pound boxes of oranges were produced. INDUSTRY DECLINEIn 2004, multiple hurricanes crisscrossed the Florida peninsula. They were the first hurricanes to hit the citrus-producing area of Florida since Hurricane Dora in 1964. The hurricanes themselves …

requirements

HLB Quarantine Requirements Updated for California

Daniel Cooper California Corner, HLB Management, Regulation

California’s Citrus Pest and Disease Prevention Division (CPDPD) has officially updated the requirements for moving bulk citrus fruit within and from a huanglongbing (HLB) quarantine area to a packer/processor. CPDPD is part of the California Department of Food and Agriculture. Here’s an overview of the newly updated requirements, per the CPDPD’s Citrus Grower/Grove Manager Information page: All fruit, no matter …

HLB-affected

Root Nutrient and Fertilization Guidelines for HLB-Affected Trees

Daniel Cooper Nutrition, 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 …

planning

Planning Pointers for Cold-Hardy Citrus Production

Daniel Cooper Cold Hardy, Production

Crop planning is an essential part of the citrus production process. What are you going to grow? Where are you going to market? How are you going to overcome HLB (huanglongbing or citrus greening)? John Chater, assistant professor at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center, discussed the different factors that …

citrus trees

Prolong the Health of Young Citrus Trees

Daniel Cooper HLB Management, Tip of the Week

By Fernando Alferez, Ute Albrecht, Ozgur Batuman, Jawwad Qureshi and Saoussen Ben Abdallah Individual protective covers (IPCs), which are psyllid-exclusion mesh bags, are increasingly being adopted to efficiently protect newly planted citrus trees from huanglongbing (HLB) infection. However, IPCs typically must be removed after two to three years due to tree growth. Early evidence indicates that brassinosteroids (Brs), a relatively …

New Decay Control Options on the Horizon for Florida Citrus

Josh McGill Fresh, Research

By Mark A. Ritenour and Jiuxu Zhang Preventing decay of fresh fruit has always been critical for a successful citrus industry. Prior to citrus greening (huanglongbing or HLB) in Florida, effective decay control practices were well established. These practices fueled Florida’s robust fresh domestic and export citrus sales, allowing shipping durations of 21 days or more. Since the establishment of …

fruit fly

Updates on Medfly and Psyllid Quarantines in California

Josh McGill California Corner, Pests, Regulation

Agriculture officials recently established a Mediterranean fruit fly (Ceratitis capitata or Medfly) quarantine and expanded an Asian citrus psyllid (ACP) quarantine, both in California. MEDFLYFederal and state agriculture officials on Oct. 18 established the Medfly quarantine in California’s Los Angeles County. The action was taken by the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS) and …

IPCs Prove to Be Game-Changer in Citrus Production

Josh McGill IPCs, Production

By Amir Rezazadeh Citrus trees face many threats that can impact fruit development and overall tree health. Pests, including aphids, mites and other insects, can damage fruit and transmit diseases. Extreme weather events, such as hailstorms or heavy rains, can cause physical harm, leading to blemishes and reduced market value. In addition, citrus growers have faced persistent challenges because of …

Positive Perspectives on the Florida Citrus Season

Josh McGill Crop Forecast, Florida Citrus Commission

By Steve Johnson The first U.S. Department of Agriculture crop forecast of the season was announced on Oct. 12. While the forecast arrived on a stormy day, the numbers were radiant rays of sunshine for our growers, and the Florida citrus industry as a whole. Every member of this industry knows there are still hurdles to clear, and there will …

Uncovering the Cause of Greasy-Green on Grapefruit 

Josh McGill Grapefruit, Tip of the Week

By Megan Dewdney, Mark A. Ritenour and Liliana M. Cano  In the last few years, 89% of Florida grapefruit growers have struggled with a disorder that they refer to as greasy-green, leading to losses between $20,000 to $1.7 million per year. The disorder causes the fruit to have large, diffuse green patches on the rind after degreening, making it no …

Universities Receive 11 Federal Grants for HLB Research

Josh McGill HLB 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 …

Increase Yield With Shade

Josh McGill Production, Tip of the Week

By Christopher Vincent, Yu Wang and Nabil Killiny  Mild shade reduces stress, increases growth and yield, and may improve pest management under huanglongbing (HLB). It reduces high temperature and water stresses. Shade also may reduce HLB transmission by making trees less visible to Asian citrus psyllids (ACP). Shaded trees have less ACP, and shade appears to reduce the severity of …

Research Update on Oxytetracycline Injection for HLB Management

Josh McGill HLB 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 …

Trunk Injection Wounding: What You Need to Know

Josh McGill HLB Management, Tip of the Week

By Ute Albrecht and Leigh Archer  Trunk injection is an alternative technique for applying crop protection materials. This technology has now been approved to deliver oxytetracycline (OTC) for huanglongbing (HLB) management in Florida. Injections cause injury, and best practices need to be established to minimize injection-induced tree damage. University of Florida Institute of Food and Agricultural Sciences researchers (UF/IFAS) injected …

First HLB Detection in Ventura County

Tacy Callies California 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 …

A Grove-First Approach

Josh McGill HLB Management, Research

In the nearly two decades that huanglongbing (HLB) has plagued Florida citrus groves, about $1 billion has been spent in the search for solutions. A lot of great scientists in Florida and around the world have worked on the problem, and a silver bullet, if there is one to be found, has been elusive. Researchers, along with growers, have developed …

Gene Confers Resistance to HLB and Citrus Canker

Josh McGill HLB 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 McGill Breeding, 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), …

California and Arizona Citrus Projects Funded

Josh McGill California Corner, Research

The California and Arizona departments of agriculture received funding for four citrus-related projects from the U.S. Department of Agriculture’s (USDA) Agricultural Marketing Service (AMS) for 2023. Nationwide, USDA AMS allocated $72.9 million in Specialty Crop Block Grant Program funding. DROUGHT-TOLERANT VARIETIESThe California Department of Food and Agriculture (CDFA) received $499,921 for designing drought-tolerant specialty crops using metabolic modeling. The University …