The natural enemies Diaphorencyrtus aligarhensis and Tamarixia radiata may have a future together in California. By Ivan Milosavljević and Mark S. Hoddle Over the past 11 years, the Asian citrus psyllid (ACP)-Candidatus Liberibacter asiaticus (CLas) (manifested as citrus greening) complex has become a “duo from hell” for Florida’s citrus industry, causing a substantial negative economic effect. ACP-CLAS MANAGEMENT IN CALIFORNIA …
Implementing Insecticide Sprays for Winter Management of Psyllids
By Jawwad A. Qureshi In winter, citrus trees enter a state of quiescence due to lower light and cooler temperatures, which slows their metabolic activity. Therefore, most citrus trees do not produce new shoots during this period. These young shoots are essential for the growth of the Asian citrus psyllid (ACP), Diaphorina citri. The ACP is a small sap-feeding insect …
First Psyllid in Imperial County Tests Positive for HLB Bacteria
An adult Asian citrus psyllid (ACP) sample collected from a rural residential property in Imperial County has tested positive for Candidatus Liberibacter asiaticus (CLas), the bacteria that causes huanglongbing (HLB). The ACP sample was collected from a citrus tree on Oct. 30 and was confirmed positive for CLas on Nov. 13. This is the first confirmed CLas-positive adult ACP found …
CITRUS NURSERY SOURCE: NVDMC’s Research Initiatives for 2025–26
By Peter Chaires Last month’s Citrus Nursery Source article promised additional details on New Varieties Development & Management Corp.’s (NVDMC) 2025–26 sponsored projects. While there is only space for general summaries, it is important to highlight the areas of focus for each research team, and the emphasis on short-term benefits while continuing to build a foundation for the future. NVDMC …
Fundecitrus Honors California Researcher
Brazilian citrus research organization Fundecitrus (Fund for Protection of Citriculture) recently honored University of California Davis (UC Davis) Distinguished Professor Walter Leal for his outstanding contribution to citriculture. Fundecitrus emphasized the importance of Leal’s work on the Asian citrus psyllid (ACP) and citrus fruit borer. Brazilian native Leal is a member of the Department of Molecular and Cellular Biology faculty …
All In For Citrus Podcast, October 2025
The October All In For Citrus podcast features citrus under protective screen (CUPS). Over the past decade, the practice has grown in popularity due to its ability to exclude the Asian citrus psyllid and huanglongbing (HLB) disease. Roughly 1,500 acres of citrus are grown under screen in Florida with more acreage under development. Lauren Diepenbrock, associate professor of entomology at …
SAR Sprays Protect Against Psyllids, HLB and Canker
Recent research has shown that systemic acquired resistance (SAR) sprays can protect young citrus tree flushes from Asian citrus psyllid (ACP) feeding, HLB and citrus canker. ACP is the vector that spreads HLB disease from tree to tree. Researchers with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) and Bayer Crop Science report that SAR sprays can …
Silicon Benefits Citrus
A University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researcher recently highlighted a number of benefits from using silicon as a nutrient for citrus. Muhammad Shahid, assistant professor at the North Florida Research and Education Center, presented silicon research findings at the Citrus & Specialty Crop Expo in August. According to Shahid, silicon is categorized as a plant …
Psyllid Management Tactics Discussed
Control of HLB-spreading Asian citrus psyllids (ACP) can be enhanced with dormant winter sprays and a focus on spraying grove perimeters, according to Citrus & Specialty Crop Expo presenter Jawwad Qureshi. Qureshi is an associate professor of entomology at the University of Florida Institute of Food and Agricultural Sciences Southwest Florida Research and Education Center. DORMANT SPRAYS In making the …
Psyllids and HLB Spreading in Georgia
Populations of Asian citrus psyllids (ACP) have been found in residential and commercial citrus in Georgia’s Lowndes and Wayne counties during the past two months. ACP spread huanglongbing (HLB) disease. In several places where ACP were found, HLB-infected trees were identified nearby. University of Georgia College of Agricultural and Environmental Sciences (UGA CAES) entomologist Apurba Barman provided details about the …
Citrus Greening Quarantine Expanded in California
Federal and state agriculture officials have expanded the quarantine for citrus greening in the Perris area of Riverside County in California by 33 square miles. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) in cooperation with the California Department of Food and Agriculture (CDFA) expanded the quarantine. The measure parallels the intrastate quarantine that CDFA established …
Preventing Citrus Greening Establishment in Georgia Groves
Citrus greening disease has yet to find its footing in Georgia. But that doesn’t mean it can’t or won’t eventually. Mary Sutton, University of Georgia assistant professor and citrus Extension specialist, discussed the ramifications of citrus greening during the recent Southeast Citrus Update in Lyons, Georgia. “If we get greening established here, we’ll start seeing lower and lower production on …
Honeymoon Phase for Georgia Citrus Production
Georgia citrus growers are still in the honeymoon phase of production with regards to disease, said Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist. While established groves in Florida have had to deal with disease buildup for decades, disease has yet to be problematic for South Georgia citrus production. But that could be changing. “With respect …
Managing Psyllids in Groves and Protected Structures
By Jawwad A. Qureshi The impact of the Asian citrus psyllid continues to intensify through devastation of its vectored huanglongbing (HLB) disease. Although there is no permanent solution for HLB yet, psyllid suppression reduces its impact. Chemical control is the most implemented method. Its strategic use helps reduce psyllid resistance and collateral damage to non-target organisms, including beneficial organisms needed …
Citrus Greening Quarantines Expanded in California
Federal and state agriculture officials recently expanded the areas quarantined for citrus greening disease in California. They expanded the quarantined area in the Coto de Caza area of Orange County by 11 square miles, the Rancho Santa Margarita area of Orange County by 93 square miles, the Perris area of Riverside County by 37 square miles, and the Rancho Cucamonga …
Potent Compound for Psyllid Control
A recent article by the São Paulo Research Foundation explains how a potent compound might aid in controlling the Asian citrus psyllid, the vector of citrus greening disease. In São Paulo, greening is managed in part by controlling the psyllid. In an attempt to manipulate psyllid behavior, a team of scientists discovered α-copaene, a molecule present in large quantities in …
Biological Control: A Significant Component of Citrus IPM
By Jawwad A. Qureshi All citrus pests in Florida have natural enemies, although some are more effective at biological control than others. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers have been studying the activity and impact of natural enemies on pest infestations in traditional open production systems and protected systems such as citrus under protective screen …
OTC Impacts on HLB in Trees and Psyllids
During the recent Florida Citrus Industry Annual Conference, Kirsten Pelz-Stelinski, director of the University of Florida Institute of Food and Agricultural Sciences Mid-Florida Research and Education Center, presented evaluations of trunk-injected antimicrobials for HLB management. She said the purpose of these antimicrobial treatments is a short-term or stop-gap approach to keep the current inventory of Florida citrus trees in the …
Boost Citrus Health and Yield With Silicon
By Muhammad A. Shahid and KeAndre Leaks Silicon (Si) is an emerging powerhouse in citrus production, offering wide-ranging benefits for plant health, fruit quality and stress resilience. While not traditionally considered essential, silicon was officially recognized as a “plant beneficial substance” in 2012 by the American Association of Plant Food Control Officials. Its inclusion as an approved input by the …
All In For Citrus Podcast, June 2025
In the June All In For Citrus podcast, Michael Rogers gives an update on some of the activities keeping University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers busy this summer. Rogers is the director of the UF/IFAS Citrus Research and Education Center in Lake Alfred. One of their big projects is helping to coordinate the citrus seminars …




























