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
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 …
Updates on Medfly and Psyllid Quarantines in California
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
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
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
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
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
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
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
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
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
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
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
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
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 …
Fundecitrus Researchers Honored for HLB Article
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, …
Update on Citrus Greening in Georgia Groves
Citrus greening disease is no longer just a problem in residential trees in Georgia. For the first time last year, citrus greening, also known as huanglongbing or HLB, was observed in commercial plantings in Pierce, Wayne and Grady counties, says Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist. Oliver discussed the disease during a citrus meeting …
Connecting Research for Better HLB Management Results
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 …
The Benefits of Growing Citrus on UV-Metalized Reflective Mulch
By Jawwad 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) or citrus greening disease. ACP, the vector of the pathogen responsible for causing HLB in citrus, needs young shoots to develop and reproduce. The frequent availability of viable shoots in young trees …
Return-on-Investment Potential of CUPS
By Ariel Singerman and Arnold W. Schumann To exclude the Asian citrus psyllid (ACP, Diaphorina citri) vector of huanglongbing (HLB) and thereby produce disease-free healthy fruit, fresh citrus can be grown under protective screen structures. The expected economic benefit from adopting citrus under protective screen (CUPS) and excluding the ACP is increased yield and quality of fruit, which in turn, are …