Another early-detection method being developed works by smelling huanglongbing infections in trees. This method detects the different scents plants give off. Researchers at the University of California, Davis have created a test that could lead to advances in fighting huanglongbing (HLB) disease in citrus. Researcher and professor of mechanical and aerospace engineering, Christina Davis, said the test looks for a …
CUPS Success Rate a Relief for Researcher
The success of citrus under protective screen (CUPS) in protecting Florida citrus from citrus greening, also known as huanglongbing or HLB, was not surprising to Arnold Schumann. The professor of soil fertility and water quality at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center is thankful research had yielded a temporary solution …
Improving ACP and HLB Control in Residential Settings
By Romain Exilien and Xavier Martini Residential gardens serve as reservoirs for Asian citrus psyllids (ACP) and citrus greening disease (also known as huanglongbing or HLB) due to unmanaged citrus trees. The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) conducted a survey to assess residents’ needs regarding ACP and HLB management. The survey examined their current control …
HLB Confirmed on California Inactive Citrus Acreage
The California Department of Food and Agriculture (CDFA) has confirmed the detection of the citrus plant disease huanglongbing (HLB) in inactive citrus acreage in the city of Yorba Linda, Orange County. The detections mark the first time HLB has been confirmed in plant samples on non-residential, non-nursery citrus acreage. The detection site, which is not currently operational or being cultivated …
California HLB Quarantine Expanded
Agricultural officials recently expanded the areas in California quarantined for citrus greening disease [also known as huanglongbing (HLB)], which is spread by Asian citrus psyllids. The quarantined area in Orange and Riverside counties was increased by a total of approximately 31 square miles. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) in cooperation with the …
Australian Lime Interstocks to Combat HLB
By Ozgur Batuman, Sanju Kunwar and Ana Redondo In a promising effort to protect citrus from huanglongbing (HLB), University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers are exploring the potential of Australian lime as an interstock graft for Valencia scions with Swingle rootstock. The interstock technique uses various limes, known for their natural HLB-tolerant peptides, between the …
Disease Concerns for Georgia Growers
Not all citrus disease concerns center around huanglongbing (HLB). While HLB disease garners much of the headlines because of its devastation to Florida’s citrus crop, growers in the cold-hardy citrus region should be mindful of other diseases that can devastate a crop if left untreated. Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist, highlighted some of …
Top Pruning Evaluated as HLB Strategy
A Brazilian study evaluated the effects of top pruning on orange trees located on the edges of an orchard as part of an HLB management strategy. The pruning was an attempt to attract the HLB-spreading psyllid from external areas to the orchard edges and control it, reducing its dispersion into the orchard. Fundecitrus and Embrapa Cassava and Fruits conducted the …
Immediate Response Required When Managing HLB
The first chore for growers in the cold-hardy citrus region when managing citrus greening is scouting for the disease and its vector, the Asian citrus psyllid. The next step is prompt removal of any trees infected with the disease, says Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist. “At this point, we think greening is still …
Citrus-Derived Endophytes Have HLB Management Potential
Florida-based scientists published an article in Microorganisms indicating citrus-derived endophytes have potential for managing HLB. Endophytes are endosymbionts, often bacteria or fungi, which live within a plant for at least part of its life cycle without causing apparent disease. The authors of the article are Jessica Dominguez, Krishnaswamy Jayachandran and Kateel G. Shetty of Florida International University, and U.S. Department …
Update on Orange Juice Processing in São Paulo
Orange juice processing for the 2024–25 season was moving at a good pace in Brazil’s São Paulo state at the end of September, the Center for Advanced Studies on Applied Economics (CEPEA) at the University of São Paulo reported. The Pera orange has been the most processed variety so far, but the harvesting and processing pace of late fruit such …
Citrus Disease Quarantines Expanded in California
U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA/APHIS) officials, in cooperation with the California Department of Food and Agriculture (CDFA), recently expanded the areas quarantined for huanglongbing (HLB) and sweet orange scab (SOS) in the state. HLB The quarantined area in Los Angeles, Orange and Riverside counties has been expanded by approximately 50 square miles. Additionally, the …
Frequent Irrigation Benefits HLB-Infected Sweet Orange Trees
By Tripti Vashisth and Mary Sutton Citrus trees affected by huanglongbing (HLB) show significant root dieback. This dieback results in smaller root systems than would be seen in healthy citrus trees. These small root systems are limited in their uptake capacity. In other words, if an HLB-affected tree is given the same amount of water as a healthy tree, the …
HLB and Psyllids in Georgia Commercial Citrus
One of Georgia citrus growers’ worst fears is slowly becoming a reality. Citrus greening, also known as huanglongbing (HLB), was observed in a Georgia commercial citrus grove for the first time in 2023. This is alarming news for the industry, says Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist. “We knew HLB was here in residential …
Specialty Crop Block Grant Program Funds Citrus Projects
The U.S. Department of Agriculture Agricultural Marketing Service (USDA AMS) Specialty Crop Block Grant Program awarded 54 grants and 524 sub-award projects totaling $72.9 million for fiscal year 2024. The following citrus projects were included in the funding. CALIFORNIA The California Department of Food and Agriculture (CDFA) received a grant for $448,742 for mitigating huanglongbing (HLB) in citrus using naturally-derived …
Repository Is ‘Insurance Policy’ for Australian Citrus
Through Hort Innovation investments on behalf of growers and the Australian government, the National Citrus Repository Program has been established as an ‘insurance policy’ to protect Australia’s citrus industry against destructive, incurable diseases. The repository houses more than 120 publicly-owned true-to-type ‘foundation tree’ variety clones so growers can access clean, disease-free planting material for assured quality and yield protection. According …
California Quarantine Updates
Federal and state officials have removed and reduced Oriental fruit fly (OFF) quarantines in two California counties and expanded the huanglongbing (HLB) quarantine in another county. The actions were taken by the U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) and the California Department of Food and Agriculture (CDFA). ORIENTAL FRUIT FLY On July 5, the …
CLas-Positive Psyllid Sample in Riverside County
An adult Asian citrus psyllid (ACP) sample from a residential property in the San Jacinto Valley area of Riverside County, California, has tested positive for Candidatus Liberibacter asiaticus (CLas), the bacterium that causes huanglongbing (HLB). The positive sample was collected as part of the Multi-Pest Risk Survey on a residential property in Hemet. It was confirmed positive for CLas on …
No Shortage of Australian Orange Juice
Citrus Australia has assured Australian consumers they will continue to have consistent access to orange juice made from locally grown fruit. Adverse growing conditions and the spread of the huanglongbing (HLB) disease have reduced orange production in Brazil, Florida and several other key citrus-growing regions around the world. This has created a global shortage of orange juice concentrate, prompting media …
Citrus Nutrient Research Update
By Davie Kadyampakeni, Muhammad Shahid and Alisheikh Atta Current citrus nutrient guidelines are based on studies of healthy citrus trees conducted in the pre-huanglongbing (HLB) era. These guidelines may no longer be valid for the present situation where 100% of mature citrus trees in Florida are HLB-affected. Scientists at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) …