California Fruit and Vegetable

Tag: Asian Citrus Psyllid

  • Huanglongbing Quarantine Boundary Expands in Riverside, SD Counties

    Effective September 11, 2026, the Department is expanding the citrus greening disease boundary in the Murrieta area of Riverside County and into San Diego County (grids 484, 499, and 510). A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/hlb/regulation.html. 

    Also effective September 11, 2026, the Department is expanding the Asian Citrus Psyllid Bulk Citrus Regional Quarantine Zone 6 in these areas to reflect the HLB quarantine boundary expansion. A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/acp/regulation.html.

    Regulated articles and conditions for intrastate movement under the quarantine can be found at Title 3 of the California Code of Regulations (CCR) section 3435 & 3439. Pursuant to 3 CCR § 3435 & 3439, any interested party or local entity may appeal a quarantine area designation. 

    Process to Appeal the Expanded Boundary 

    The appeal must be submitted to the Department in writing and supported by clear and convincing evidence. The appeal must be filed no later than ten (10) working days from the date of this notification. During the pending of the appeal, the designated quarantine boundary under appeal shall remain in effect. 

    Mail Appeals to: CDFA – Citrus Division 1220 N Street Sacramento, CA 95814 

    Electronic Notification of Boundary Changes 

    California Code of Regulation allows interested parties to be notified of quarantine area boundary changes, as well as the opportunity to submit quarantine boundary appeals. If interested in receiving notifications, please sign up for regulatory updates through the email notification at: https://public.govdelivery.com/accounts/CADFA/subscriber/new 

    For questions regarding the regulations or map, please email Raymond Niem (Raymond.Niem@cdfa.ca.gov) or call 916-274-6300. — Story contributed by the California Department of Food and Ag

  • Huanglongbing Quarantine Boundary Expands in Riverside, San Diego Counties

    Effective July 29, the Department is expanding the HLB quarantine boundary in the Fallbrook and Rainbow areas of San Diego County and into Riverside County (grids 499 and 500). A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/hlb/regulation.html.

    Also effective July 29, the Department is expanding the Asian Citrus Psyllid Bulk Citrus Regional Quarantine Zone 6 in the both areas to reflect the HLB quarantine boundary expansion. A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/acp/regulation.html.

    Regulated articles and conditions for intrastate movement under the quarantine can be found at Title 3 of the California Code of Regulations (CCR) section 3435 & 3439. Pursuant to 3 CCR § 3435 & 3439, any interested party or local entity may appeal a quarantine area designation.

    Process to Appeal the Expanded Boundary

    The appeal must be submitted to the Department in writing and supported by clear and convincing evidence. The appeal must be filed no later than ten (10) working days from the date of this notification. During the pending of the appeal, the designated quarantine boundary under appeal shall remain in effect.

    Mail Appeals to: CDFA — Citrus Division 1220 N Street Sacramento, CA 95814

    Electronic Notification of Boundary Changes

    California Code of Regulation allows interested parties to be notified of quarantine area boundary changes, as well as the opportunity to submit quarantine boundary appeals. If interested in receiving notifications, please sign up for regulatory updates through the email notification at: https://public.govdelivery.com/accounts/CADFA/subscriber/new

    For questions regarding the regulations or map, email Raymond Niem (Raymond.Niem@cdfa.ca.gov) or call 916.274.6300.

    — Story contributed to the California Department of Food and Agriculture

  • Citrus Research Board to Host Webinar Series

    The Citrus Research Board (CRB) is preparing to host the 2026 Citrus Growers Educational Webinar Series. CRB will be holding two one-hour webinars, scheduled for June 9 and 23, which will highlight research and discussions for growers.

    The first webinar, “Plant Growth Regulators and California Citrus — Review and Updates,” will review the plant growth regulators (PGRs) currently available to the California citrus industry. This will include uses and effects of each of the PGRs covering both a historical perspective and current needs. The importance of 2,4-D timing will also discussed with respect to the premature fruit drop observed in Fall 2025.

    Registration for the June 9 webinar can be done here.

    The second webinar, “On the Ground with CA-CRaFT,” was started by California Research and Field Trials in 2023 to develop practical, field-based ACP management strategies under real commercial conditions across California. A major focus of this webinar will be updates on canine-assisted Asian citrus psyllid (ACP) inspections, field scouting, tap sampling, sticky traps and drone imagery are being integrated to support regional ACP management decisions and strengthen early detection efforts. Additional updates will include planned expansion of CA-CRaFT activities into Ventura County with stronger emphasis on biological control using self-release Tamarixia radiata cage systems. Ongoing Argentine ant management efforts will also be discussed, as invasive ants continue to be an important factor Tamaraxia establishment and overall biological control success in California citrus.

    Registration for the June 23 webinar can be done here. — Story contributed by the Citrus Research Board

  • Citrus Greening Quarantine Expands in Southern California

    Effective immediately, the Animal and Plant Health Inspection Service (APHIS), in cooperation with the California Department of Food and Agriculture (CDFA), is expanding the area quarantined for citrus greening (Huanglongbing), caused by the Asian citrus psyllid, in California. APHIS is establishing a new quarantined area in the Ramona area of San Diego County of 93 square miles and is expanding the quarantined area in the Loma Linda area of San Bernardino and Riverside Counties by 26 square miles. These measures parallel the intrastate quarantines that CDFA established on March 2, and March 6, 2026, respectively. APHIS is taking this action because of citrus greening detections in plant tissue samples collected from residential properties. There are 25.16 acres of commercial citrus impacted by the new Ramona quarantine and 411.47 acres of commercial citrus impacted by the Loma Linda area expansion.

    APHIS is applying safeguarding measures outlined in 7 CFR 301.76 and Federal Orders pertaining to the interstate movement of regulated articles from the quarantined areas in California. This action is necessary to prevent the spread of citrus greening to non-infested areas of the United States.

    The APHIS Citrus Greening webpage contains specific changes to the quarantined areas in California. APHIS will publish a notice of this change in the Federal Register.

  • UC Seeks Consumers to Weigh in on New Method of Controlling Asian Citrus Psyllids

    To understand consumers’ attitudes toward a bioengineered pesticide for citrus crops, University of California Agriculture and Natural Resources researchers are asking for volunteers to participate in focus groups in Riverside, Oakland and Fresno.

    Bacillus thuringiensis, or Bt, is a naturally occurring bacterium being tested to control the spread of Asian citrus psyllid, the small insect that transmits the disease huanglongbing to citrus trees. Both the Asian citrus psyllid and huanglongbing have been found in Southern California backyard citrus trees and threaten to spread throughout the state.

    Huanglongbing, also known as citrus greening disease, is a bacterial infection that stunts citrus trees, reduces their fruit production, deforms and greens the fruit and eventually kills the tree. There is no known cure or effective control.

    The disease has already devastated Florida’s citrus industry, slashing the state’s orange production by 92% between 2005 and 2025, according to Karen Jetter, associate director and project economist at the UC ANR Policy Institute. By the time the magnitude of the problem was revealed, both Asian citrus psyllid, or ACP, and huanglongbing were widespread in Florida.

    “In California, we still have the opportunity to slow the spread of huanglongbing through ACP management,” Jetter said.  “This unique technology is designed to be part of a comprehensive ACP management program, not to replace it.”

    Jetter and Fiona Ogunkoya, survey researcher at the UC ANR Policy Institute, are conducting focus groups to assess consumer attitudes toward an engineered Bt pest control method that targets Asian citrus psyllids, the primary vector of the disease, to stop the spread of huanglongbing.

    The bioengineered pest control strategy, developed in Florida and shown to be effective, uses an engineered citrus tristeza virus to transmit an engineered Bacillus thuringiensis to citrus trees. The Asian citrus psyllid lays eggs on the tender new leaf growth of the trees. After the nymphs hatch, the immature insects consume the modified Bt-infected leaves, become sick and die.

    California citrus growers surveyed by Sandipa Gautam, UC Cooperative Extension integrated pest management citrus advisor, said they are interested in the approach. But they growers are concerned that consumers will not accept fruit grown with this new bioengineered insecticide.

    To find out what consumers think, the researchers will meet with three focus groups, with each session limited to six to eight people to allow all participants time to express their thoughts.

    The 90-minute focus group meetings will be held at UC Cooperative Extension offices in Riverside on March 30 at 6 p.m., in Oakland on April 6 at 2 p.m. and in Fresno on April 8 at 2 p.m. Pizza will be served.

    To participate in a focus group, register for a session at https://forms.gle/QPyUd7QazTLfNdATA. To be eligible, participants must be 18 years of age or older and able to attend the focus group in person. — By UC Agriculture and Natural Resources

  • Using Predators to Counter Asian Citrus Psyllids

     

    The Asian citrus psyllid is an active threat for growers and the main vector for Huanglongbing disease. These invasive insects have wreaked havoc in Florida and spread to Southern California, but researchers at UC Riverside are finding ways to counter them. Matthew Malcolm from Malcolm Media Ag Publishing interviewed Bodil Cass at the World Ag Expo to discuss the use of predators against psyllids. Watch this quick video and read more in California Fruit & Vegetable Magazine.

    Please thank this video’s sponsor Simplot for their industry support.

  • UC Davis Professor Honored for Citrus Pest Research

    UC Davis Distinguished Professor Walter Leal recently received an award from the citrus research organization, FUNDECITRUS,  São Paulo, Brazil, in recognition of his “outstanding contribution to citriculture, emphasizing his work on the Asian citrus psyllid and a Lepidopteran pest named “bicho furão” (citrus fruit borer).

    Leal, a member of the Department of Molecular and Cellular Biology faculty and a former professor and chair of the UC Davis Department of Entomology, is the first U.S.-based researcher to receive the FUNDECITRUS. award.

    A native of Brazil and a Fellow of both the Entomological Society of America and the Entomological Society of Brazil, Leal is the principal investigator of a research agreement between UC Davis and the Fundecitrus-Fund for Protection of Citriculture, based in São Paulo.

    Leal’s discovery of the sex pheromone of the Asian citrus psyllid–which spreads the deadly citrus greening disease, Huanglongbing (HLB)–may result in the insect version of “The Fatal Attraction.” The team is now working on a formulation to be used in traps.

    The Asian citrus psyllid, Diaphorina citris, is a sap-sucking bug that is one of two confirmed vectors of HLB. A native of Asia, it is found in parts of the Middle East, South and Central America, Mexico, and the Caribbean. It was first detected in the United States in 1998 (Palm Beach County, Florida) and is now also found in Louisiana, Georgia, Arizona, South Carolina, Texas, and since 2003, in California  (San Joaquin Valley and Central Coast counties, including San Luis Obispo.)

    Former UC Cooperative Extension advisor Surendra Dara of San Luis Obispo and Santa Barbara counties (now at the University o Hawaii, Mānoa) earlier said that “The Asian citrus psyllid is a major threat to the multibillion dollar citrus industry in the United States. When an insect pest vectors a deadly disease, the threat is more serious and ACP being an invasive pest made its management even more challenging.  Discovery of a sex pheromone by Dr. Leal’s team is a major breakthrough not just for managing a dangerous invasive pest, but also a significant contribution to environmental sustainability.  I envision this pheromone becoming a clean, green, mean weapon in the IPM arsenal against ACP.”.

    Integrated pest management specialist and UC Davis Distinguished Professor Emeritus (on recall) Frank Zalom, of the UC Davis Department of Entomology and Nematology and a past president of the Entomological Society of America, earlier hailed the discovery as a “significant breakthrough in preventing the spread of this serious citrus insect, and may offer a less toxic method for its control.” He was not involved in the study.

    Pheromones and other semiochemicals are widely used in agriculture and medical entomology. “Growers use them as lures in trapping systems for monitoring and surveillance, as well as for strategies for controlling populations, such as mating disruption and attraction-and-kill systems,” Leal noted.

    ACP feeds on new leaf growth of oranges, lemons, mandarins, grapefruit and other citrus, as well as some related plants. Infected psyllids can transmit the bacterium Candidatus Liberibacter asiaticus, which causes the fatal citrus disease. An early symptom of HLB in citrus is the yellowing of leaves on an individual limb or in a sector of a tree’s canopy.

    Citrus trees infected with HLB usually die within five years, according to the UC Statewide Integrated Pest Management Program. There is no known cure. “The only way to protect trees is to prevent spread of the HLB pathogen in the first place, by controlling psyllid populations and removing and destroying any infected trees,” UC IPM says on its website.

  • Ants Protect Deadly Citrus Disease Vector – New Ant Management Tools

    Ants are known to interfere with biological control of key citrus pests because they feast upon the sugary honeydew produced by small insects. One of these key pests is the invasive asian citrus psyllid that vectors the deadly huanglongbing citrus disease. As California growers diligently work to keep this disease out of citrus orchards, effective ant management is a critical component in the game plan. Ivan Milosavljevic from the California Citrus Research Board met with Matthew Malcolm on California Ag Network to discuss some new game-changing control strategies. Watch this brief interview and read more about it in California Fruit & Vegetable Magazine.

  • Funding Available for California Citrus Growers to Fight Asian Citrus Psyllid, Prevent Citrus Disease

    Huanglongbing (HLB), the deadly citrus disease that decimated the Florida citrus industry has shown up in Southern California and is now threatening the nation’s number one citrus state.  HLB is primarily spread by the invasive Asian Citrus Psyllid, so managing this insect is key to preventing the spread of the disease. Pest mitigation practices may be costly, the California Citrus Research Board (CRB) introduced the California Citrus Research and Field Trials program (CA-CRaFT) to help fund commercial growers (both conventional and organic) to implement these practices. CRB representative Ivan Milosavljevic met with Matthew Malcolm on California Ag Network to share details. Watch this brief interview and read more in California Fruit & Vegetable Magazine.

  • Citrus Growers Encouraged to Increase Vigilance Following Recent ACP Detections in Central Valley

    Following recent Asian citrus psyllid (ACP) detections in the Central Valley over the last few weeks, growers, packers, haulers and all citrus industry members are encouraged to be extra vigilant in their ACP mitigation steps and adherence to regulatory practices.

    Recently, multiple ACP were detected on traps at a packinghouse in the Woodlake area of Tulare County. Upon confirmation, visual delimitation surveys began the following day. Live adults or nymphs were found and collected at two more adjacent properties, including an abandoned parcel with citrus host plants. CDFA is working closely with the packinghouse to ensure regulatory compliance. Treatment of host plants on residential properties within 400 meters of the detection will be conducted by CDFA once all necessary notifications, emergency proclamations and public meetings have been held. Commercial citrus operations within 800 meters of the detections will be asked to conduct treatments as well.

    Additionally, one ACP was recently detected on a trap at a juice plant in Visalia, and upon completion of the visual delimitation survey of the find site and adjacent properties, there were no additional finds.

    In Kern County, three ACP trap detections have been identified in the last week. One in the city, and two in rural residential locations in Southwest Bakersfield. These are the first ACP detections found in Kern County since November 2021. CDFA teams have already begun delimitation surveys and treatments will be conducted on residential properties with host plants within a 50-meter area around the detections once proper notifications, emergency proclamations and public meetings have been held. There are no commercial operations for several miles around the Kern County detections.

    These detections are a resounding reminder to continue to follow ACP mitigation best practices and regulatory requirements to efficiently suppress ACP populations and prevent the spread of Huanglongbing to the Central Valley.

     

    If you suspect ACP or Huanglongbing in your orchard, please notify the California Department of Food and Agriculture Pest Hotline at 1-800-491-1899. For questions, contact Kern County Grower Liaison Judy Zaninovich at jsleslie@msn.com, Northern Tulare County Grower Liaison Teri Blaser at tblasersci@ocsnet.net or Southern Tulare County Grower Liaison Jessica Leslie at jess.leslie@hotmail.com.