Scientists at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) are testing a new type of citrus tree that can fight off the HLB-spreading Asian citrus psyllid (ACP). The genetically modified tree has only been tested in the lab and the greenhouse but is very promising as a potential solution to HLB. The approach involves inserting a …
Psyllid Insecticides Effective in Brazil’s New Citrus Regions
Citrus growing is migrating to additional areas in Brazil, such as the Triângulo Mineiro region, the northwest of of São Paulo and Mato Grosso do Sul. For this reason, Fundecitrus began testing insecticides in these areas and observed that some products, to which the HLB-spreading psyllid is often resistant, performed well in the initial evaluation. Fundecitrus researcher Marcelo Miranda said …
Planting Layout Reduces HLB-Spreading Psyllids
A Brazilian study has shown that planting citrus plots parallel to the property boundary reduced HLB-spreading psyllids 12% to 23% compared to plots planted perpendicular to the property boundary. Fundecitrus conducted the study. The São Paulo Research Foundation co-financed it in partnership with Embrapa. Another study conclusion is related to the impact of planting density on border plots. Fundecitrus researcher …
Control of Asian Citrus Psyllids and Leafminers
Biological control can have a significant impact on Asian citrus psyllid (ACP) and citrus leafminer (CLM) populations in Florida, a researcher reported in a Nov. 19 virtual meeting. Jawwad Qureshi, associate professor of entomology with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), also discussed some cultural and chemical controls that work on the pests. ACP Qureshi, …
Psyllid Control Discussed at South African Citrus Symposium
Researchers Marcelo Miranda and Haroldo Volpe with Brazil’s Fundecitrus discussed control of the HLB-spreading psyllid during a recent visit to a South African research symposium and accompanying events. During the Citrus Research Symposium in Drakensberg, Miranda discussed studies developed at Fundecitrus on the management of the HLB-spreading psyllid (Diaphorina citri). In South Africa, HLB is caused by a bacteria different …
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 …
Psyllid Nanopesticide Developed in Brazil
In Brazil, a more effective and sustainable insecticide for HLB-spreading psyllids was developed by Embrapa (Brazilian Agricultural Research Company) in partnership with the Institute of Chemistry of the State University of Campinas (Unicamp). The work resulted in a controlled-release system of the insecticide thiamethoxam molecule. Encapsulation was performed in polymeric nanoparticles, structures more than 80,000 times smaller than the thickness …
Fundecitrus Declares ‘Battle Time’ Against Psyllids
Brazil’s Fundecitrus recently declared battle in the fight against HLB-spreading psyllids. The citrus association’s recently launched “It’s battle time!” advertising campaign reinforces the need for rigor in psyllid control during the most critical period of the year. It is at this time, between the end of winter and spring, that high numbers of psyllids are captured in traps installed in …
Greening Bacterium Causes Changes in Psyllids
Recent studies, including a partnership project between Fundecitrus and the University of California, revealed that the citrus greening bacterium Candidatus Liberibacter asiaticus causes physiological changes in psyllids, posing additional challenges to management strategies. An increase in the number of eggs, more frequent dispersal flights over longer distances and greater attractiveness to the host are some of the changes observed in …
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 …
Study Sheds Light on Defense Against HLB-Spreading Psyllids
A study by researchers from the Guangdong Academy of Agricultural Sciences and South China Agricultural University sheds light on the genetic mechanisms that can defend against Asian citrus psyllid (ACP) infestation. ACP is the vector for HLB, the most devastating disease of citrus. The study was published in Horticulture Research on April 1. It unveils the roles of two cytochrome …
Biological Control Leads to ‘Massive Decline’ in Psyllids
Repeated evaluations throughout California showed “a massive decline – greater than 70%” in HLB-spreading Asian citrus psyllid (ACP) densities since the inception of a biological control program, a researcher reported recently. Mark Hoddle said the University of California, Riverside (UCR) and the California Department of Food and Agriculture (CDFA) turned to biocontrol because insecticide spraying wasn’t adequately controlling the psyllid. …
CitrusMimic Detects Greening and Kills Psyllids
A University of Miami (UM) doctoral candidate won third place in the UM College of Engineering’s Rothberg Catalyzer Pitch Competition for creating an instrument to quickly detect airborne traces of citrus greening disease. Shruti Choudhary’s creation, CitrusMimic, would be deployed on farming equipment to continuously draw in air and test for the citrus greening bacteria spread by the Asian citrus …
‘The Psyllids Will Like Georgia Just Fine’
A California citrus leader believes Georgia will make an ideal home for the Asian citrus psyllid, which vectors the devastating huanglongbing (HLB) disease. “North of Florida, it is colder, and it’s certainly not as suitable a place as Florida is, but the psyllid is still going to be fine. The cold isn’t long enough here to knock the populations out,” …
Mexican Organic Orchards Offer Better Psyllid Control
A wider diversity of weeds and insects in organic Mexican citrus orchards compared to conventional orchards aids in control of the HLB-spreading Asian citrus psyllid (ACP/Diaphorina citri), a Mexican scientist reported recently. HLB is also known as citrus greening disease. “In the organic orchard, there are almost double the species of weeds compared to the conventional orchard,” Carlos Castillejos Cruz …
New Tool Will Help Brazilian Growers Manage Psyllids
Fundecitrus has launched Evaluate Psyllid, a tool that will help citrus growers choose insecticides to manage the pest that spreads citrus greening disease. Evaluate Psyllid will make available the results of insecticide efficacy experiments on field psyllid populations in different regions of Brazil’s citrus belt. The insecticide efficacy data will be constantly updated as experiments are carried out. It will …
Pheromone-Based Psyllid Control Not Viable
Studies with psyllid pheromones show that the insect’s behavior is altered when it is infected by the HLB-causing bacterium Candidatus Liberibacter (CLas). This makes it difficult to produce a commercial psyllid-control product based on the insect pheromone, Brazil’s Fundecitrus has concluded. “The sexual pheromone is an attractant produced by the female of the species, which promotes behavioral changes in male …
New Discovery About Asian Citrus Psyllids
A failed field test has led to a major discovery about Asian citrus psyllids (ACP). According to new research, the bacterium that causes HLB disease can interfere with ACP’s sense of smell, rendering some kinds of insect traps useless. The work is currently available as a preprint. HLB, also known as citrus greening, is caused by the Candidatus Liberibacter asiaticus (CLas) bacterium. …
Mulch Suppresses Psyllids in Young Trees
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 …
Bud Advisories Help Growers Time Psyllid Sprays
The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) is reminding citrus growers that flower bud advisories are now being issued. The UF/IFAS advisories can help growers determine when to spray for HLB-spreading Asian citrus psyllids and when to stop spraying in an effort to protect pollinating bees. Tripti Vashisth, a UF/IFAS associate professor of horticultural sciences, will …

























