study

Psyllids Resistant to Insecticides in Brazil

Josh McGillBrazil, HLB Management

Psyllids collected in orchards in four microregions of Brazil’s citrus belt showed reduced susceptibility to insecticides from the pyrethroid and neonicotinoid chemical groups. That information was reported earlier this year by agronomist and researcher Fernando Amaral of the Arthropod Resistance Laboratory at the Luiz de Queiroz College of Agriculture/University of São Paulo (ESALQ/USP). This was the first confirmation of psyllid …

Antibiotics, HLB and Psyllids

Josh McGillHLB Management, Pests

Entomologist Kirsten Pelz-Stelinski recently shared findings from trials on the use of foliar-applied and trunk-injected antibiotics for controlling HLB and the Asian citrus psyllids (ACP) that spread the disease. Pelz-Stelinski is associate center director at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center (CREC) in Lake Alfred.  In a May 17 presentation …

Silicon Could Benefit Florida Citrus

Josh McGillNutrition, Production

There has been much focus on the benefits of applications of plant growth regulators like gibberellic acid and 2,4-D, and more recently oxytetracycline hydrochloride to improve the health of citrus trees infected with HLB. Silicon also has been highlighted for its potential benefits to citrus. Mohammad Adnan Shahid, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) assistant professor, …

California Psyllid Program Requires Compliance Agreements

Josh McGillCalifornia Corner, Regulation

The California Department of Food and Agriculture’s (CDFA) Asian citrus psyllid (ACP) quarantine program now requires all harvesters/farm labor contractors (FLCs) to have valid compliance agreements to harvest citrus groves. An FLC is defined as any person or establishment that employs people to perform work related to grove management and/or harvesting commercial citrus fruit. The requirement was announced by CDFA’s …

Lebbeck Mealybug Problematic for Florida Citrus

Josh McGillPests

The lebbeck mealybug, also known as the hibiscus mealybug, is a pest that has recently become problematic for Florida citrus growers. Extension agent Lourdes Perez Cordero and entomologist Lauren Diepenbrock, both with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), recently reported on the pest. According to Cordero and Diepenbrock, the lebbeck mealybug feeds by piercing the …

New Twist Added to Psyllid Control

Josh McGillHLB Management, Pests

Lukasz Stelinski for years has promoted saving money on HLB control by spraying for Asian citrus psyllids (ACP) only when their populations reach a certain threshold. The University of Florida Institute of Food and Agricultural Sciences professor still promotes that concept, but with a slightly new twist. TRUNK INJECTION SHOWING PROMISEIn a virtual seminar on April 25, Stelinski advised growers …

Deficit Irrigation in HLB-affected Citrus Trees

Josh McGillIrrigation, Research

By Davie Kadyampakeni, Samuel Kwakye, Hossein Ghoveisi, Lauren Diepenbrock and Jawwad Qureshi Deficit irrigation practices can reduce water and energy costs, thus potentially increasing water-use efficiency and water savings in citrus production. Irrigation management through deficit applications, if timed at periods of reduced water demand, could help trigger increased root water and nutrient uptake while synchronizing citrus flush patterns. These …

Psyllids Confirmed in Sonoma County, California

Josh McGillCalifornia Corner, Psyllids

California officials have confirmed the presence of HLB-spreading Asian citrus psyllids in a residential area east of Sonoma. The confirmation came following analysis of a survey trap set by the Sonoma County Department of Agriculture. The county department is coordinating with the California Department of Food and Agriculture (CDFA) in responding to the pest’s presence in Sonoma Valley. “Discovery of …

Psyllids and HLB in Georgia Citrus

Josh McGillGeorgia, Psyllids

When commercial citrus acreage started migrating north some years ago, the big question was: To what extent would Asian citrus psyllids (ACP) and HLB migrate with the crop? With citrus getting well established in South Georgia, the pest and disease are there, but not yet at devastating levels like in Florida. Johnathan Oliver, an assistant professor of fruit pathology with …

Blanket Flowers Increase Arthropod Predators and Pollinators in Citrus Groves

Josh McGillPest Management, Pollination, Research

By Angela Chuang and Lauren Diepenbrock While many arthropod predator and pollinator activities benefit crop quality and yields, traditional farming environments may not be ideal habitats to support their survival year-round. For example, wild bees or flies that pollinate citrus may need other sources of nectar and pollen when citrus is not flowering. Planting wildflowers near crop fields to improve …

Diaprepes in Florida Citrus: Past, Present and Future

Josh McGillPest Management, Research

By Lukasz L. Stelinski, Lauren Diepenbrock and Larry Duncan Given the focus on HLB in citrus management for more than a decade, important additional pests of citrus have sometimes not received the attention they may deserve. Trees with HLB are weakened and prone to succumb to the effects of the disease when challenged by secondary affliction(s), including infestation by diaprepes …

Sneak Peek: January 2023 Citrus Industry

Josh McGillSneak Peek

Past management, a perennial problem for citrus growers, is the primary focus of the January issue of Citrus Industry magazine. An old pest is posing new concerns for Florida growers. The recent resurgence of diaprepes root weevil is the subject of the cover story by University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers Lukasz Stelinski, Lauren Diepenbrock …

California Psyllids Carrying HLB Bacterium in Groves

Tacy CalliesCalifornia Corner, Psyllids

An ongoing study in coastal Southern California citrus groves has found that just over 3.5% of Asian citrus psyllids (ACP) tested are carrying the bacterium that can cause HLB. ACP is the insect vector of HLB. Thus far, 138 of 3,000 adult ACP collected from 15 commercial citrus sites had some level of the bacterium present. The results were reported …

Citrus Breeding Discussed During Field Day

Josh McGillBreeding, CUPS, Fresh

The focus of citrus breeding at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) differs for fruit produced for the juice market vs. fruit for the fresh market. Citrus breeder Jude Grosser, a UF/IFAS professor of plant cell genetics, spoke during the Cold-Hardy Citrus Field Day at the North Florida Research and Education Center in Quincy on …

Changing Psyllids to Make Them Incapable of Spreading HLB

Josh McGillHLB Management, Research

By Kirsten S. Pelz-Stelinski and Lukasz L. Stelinski Managing Asian citrus psyllids (ACP) remains a consideration for growers because psyllids transmit the citrus greening disease pathogen, Candidatus Liberibacter asiaticus (CLas), to newly planted trees. There are several tools that can reduce psyllid populations or mitigate the symptoms of HLB and improve the health of infected trees. However, additional methods that …

California Citrus Industry Follows in Florida’s Research Footsteps

Josh McGillCalifornia Corner, Research

By Danielle Leal During a recent trip to Washington, D.C., California Citrus Mutual (CCM) representatives visited with the U.S. Department of Agriculture and members of Congress to outline several citrus industry priorities and secure funding for research. CCM President and Chief Executive Officer Casey Creamer announced during the 2022 California Citrus Conference that the Citrus Research Board received funding from …

Citrus Industry More Effective When Collaborative

Josh McGillCalifornia Corner, Events

By Danielle Leal The 2023 California Citrus Conference in Visalia proved collaboration is pivotal when tackling industry issues. The conference, hosted by California’s Citrus Research Board, had a lineup of industry leaders, researchers and others who updated growers on California’s citrus industry. Casey Creamer, president and chief executive officer of California Citrus Mutual, spoke on strengthening the connection between research …

CUPS Update From the Citrus Research and Education Center

Josh McGillCUPS, HLB Management, Research

By Arnold Schumann, Laura Waldo, Chris Oswalt, Napoleon Mariner, Timothy Ebert, Perseveranca Mungofa, Shankar Shrestha and Laura Cano-Castro Florida grapefruit production for the 2021–22 season was 92% less than in 2003–04, which was prior to the arrival of huanglongbing (HLB) disease [Source: U.S. Department of Agriculture National Agricultural Statistics Service, (USDA NASS)]. The decrease in Florida tangerine production for the …

Fire Ant Control Aids Psyllid Management

Josh McGillCitrus Expo, HLB Management, Pests

Controlling fire ants in groves aids in the control of HLB-spreading Asian citrus psyllids (ACP), entomologist Lukasz Stelinski reported at the Citrus & Specialty Crop Expo. Fire ant control was just one way that Stelinski suggested for growers to manage ACP while reducing costs. The University of Florida Institute of Food and Agricultural Sciences entomologist said ACP populations drop when …