Ching-Hong Yang, University of Wisconsin-Milwaukee (UWM) biological sciences professor, was recently awarded a $1.5 million federal grant to support research on a compound that suppresses HLB disease. His project is titled Bringing RejuAgro to Market: Development of a Groundbreaking Trunk Injection Biopesticide for Huanglongbing (HLB). The grant is from the U.S. Department of Agriculture National Institute of Food and Agriculture …
Georgia Student Honored for HLB Research
Carlton Collins recently was named top master’s researcher in the E. Broadus Browne Research Awards for Outstanding Graduate Student Research competition at the University of Georgia (UGA) College of Agricultural and Environmental Sciences. He was recognized for his research on huanglongbing (HLB) disease, also known as citrus greening. Collins, born in Jamaica, was introduced to citrus production on a small …
Spinach Peptides Provide Defense Against HLB
Texas A&M AgriLife Research scientists have developed an approach to countering the citrus disease HLB as well as zebra chip disease in potatoes and other vegetables. Their method uses spinach antimicrobial peptides, known as defensins, which naturally defend plants against a broad range of pathogens. Their study results were recently published in the Plant Biotechnology Journal. The effects show significant …
Mechanism of Resistance to HLB Identified
A research team led by Jian Ye from the Institute of Microbiology of the Chinese Academy of Sciences has identified the first mechanism of citrus resistance to HLB. Results of the study were published in Science. Utilizing artificial intelligence (AI), the team has also developed antimicrobial peptides that offer a promising therapeutic approach to combat the disease. This discovery addresses …
Irrigation Comparison for Young HLB Trees
By Davie Kadyampakeni, Kondwani Kamsikiri and Alisheikh Atta Water scarcity is one of the major constraints in Florida citrus production systems, primarily due to erratic rainfall patterns and the low water- and nutrient-holding capacity of the predominantly sandy soils. The state’s soils contain more than 95% sand and have low organic matter (<1%) and very low water-holding capacity. These challenges …
HLB-Tolerant Varieties Available
Florida Foundation Seed Producers, Inc. (FFSP) has signed a licensing agreement with New Varieties Development and Management Corp. (NVDMC) to introduce new citrus varieties showing tolerance to HLB. The HLB-tolerant varieties covered by the agreement are: The collaboration also includes the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) and the Florida Department of Citrus. It aims to …
Brassinosteroids Improve HLB-Affected Tree Health and Fruit Quality
By Fernando Alferez, Divya Aryal and Saoussen Ben Abdallah In the last few years, the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) citrus horticulture team at the Southwest Florida Research and Education Center (SWFREC) in Immokalee has performed several research trials in commercial farms and at the experimental farm at the SWFREC to elucidate the effect of …
HLB Quarantine Expands in California
The California Department of Food and Agriculture (CDFA) declared a citrus quarantine expansion in San Diego County’s Valley Center on March 26. The expansion occurred after detection of HLB disease in two citrus trees in residential neighborhoods in the Valley Center area during regular inspections. HLB is a major threat to San Diego County’s $144 million annual citrus crop …
Combine Proven Horticultural Practices to Combat HLB
By Tripti Vashisth and Prudhvi Vulchi To mitigate the effects of huanglongbing (HLB) on tree health and productivity, growers are encouraged to adopt proven horticultural practices. Based on recent field trials at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center (CREC), one effective approach combines frequent irrigation (FI), plant growth regulators (PGRs) …
Separating HLB-Affected and Healthy Fruit
Scientists with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) and the U.S. Department of Agriculture Agricultural Research Service (USDA/ARS) recently wrote about efforts to identify HLB-affected versus healthy citrus fruit. UF/IFAS scientists are Mark Ritenour, Ketan Shende and Thomas Burks. Michelle Heck is with the USDA/ARS. A slightly edited version of their article follows: Most citrus …
HLB Quarantine Area Expanded in California Again
Federal and state officials have expanded the quarantine for huanglongbing (HLB, also known as citrus greening disease) in the Mission Viejo area of California’s Orange County. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS), in cooperation with the California Department of Food and Agriculture, expanded the quarantine by 13.16 square miles. The expansion was in response …
Recovering Unprotected HLB-Infected Young Trees
By Fernando Alferez and Saoussen Ben Abdallah Individual protective covers (IPCs) are now being increasingly adopted in Florida to protect newly planted citrus trees from psyllid colonization. The risk of new citrus plantings becoming infected with HLB is especially high, as young trees flush more frequently and attract more psyllids. However, the adoption of IPCs does not occur in all …
Hope for an HLB-Resistant Tree
Rick Dantzler, Citrus Research and Development Foundation (CRDF) chief operating officer, believes there is a future for Florida’s citrus industry. His optimistic outlook is based on approaches that researchers have implemented to help growers survive in the short term, such as oxytetracycline (OTC) trunk injection, and work toward the development of an HLB-resistant tree. Dantzler shared that hope during the …
Not If Georgia Will Get HLB, But When
Citrus greening disease, also known as huanglongbing (HLB), is not yet widespread in Georgia. However, there’s no reason to think that it won’t become more of a problem for the state’s citrus growers. Lindy Savelle, executive director of the Georgia Citrus Association (GCA), hopes it doesn’t happen but cautions growers about the disease’s potential beyond Florida. “Something we have to …
Mathematical Modeling Is Preparing Europe for HLB
A tool predicting how to protect European citrus from HLB shows how mathematical modeling can help prepare for future plant disease invasions. Europe is currently unaffected by HLB. However, there are increased concerns of an infestation since psyllids that spread HLB have been found in key citrus-producing countries, including Portugal and Spain. In response to the HLB threat, a new …
Emergency Program Expanded in California for HLB/ACP
The California Department of Food and Agriculture (CDFA) recently announced the expansion in Orange County of an emergency program for HLB and the Asian citrus psyllid (ACP) that spreads the disease. The expansion follows confirmation throughout January of the causative bacterial agent of HLB in plant tissue and/or ACP in Anaheim, Costa Mesa, Garden Grove, Irvine, Mission Viejo, Orange, Santa …
HLB Confirmed in Arizona for First Time
HLB was recently confirmed for the first time in Arizona, first in an Asian citrus psyllid (ACP) and then in another ACP and citrus plant tissue. The Arizona Department of Agriculture (AZDA) reported the details. On Dec. 16, 2024, agriculture inspectors collected ACP and plant tissue samples from a residential citrus tree in Nogales. The collections were made during a …
Quarantine Updates: HLB in Mississippi; Mexfly in Texas
The U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA/APHIS) recently announced a quarantine for huanglongbing (HLB) in Mississippi as well as updates to Mexican fruit fly (Mexfly) quarantines in Texas. HLB APHIS, in cooperation with the Mississippi Department of Agriculture and Commerce, established a quarantine for the entire state of Mississippi for HLB. The action was taken …
Frequent Irrigation Is Critical for HLB-Affected Trees
By Tripti Vashisth and Mary Sutton HLB-affected trees have small and weak root systems. These trees often experience water and nutrient deficit. However, not all HLB-affected trees experience the same impact. Trees with severe HLB symptoms will have higher root loss and water deficit than trees with mild HLB symptoms. The water deficit exacerbates during spring, which is often the …
Rejuvenate HLB Trees With Precision Nutrient Management
By Meryam Manzoor, Jamie D. Burrow, Taylor Livingston and Tripti Vashisth Effective nutrient management and accurate nutritional analysis are critical for tree growth and maximum yield. Historically, nutrient management for healthy citrus trees involved annual leaf sampling from July to August, with subsequent fertilization plans based on a single nutrient analysis. Almost all commercial citrus groves in Florida are affected …