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 …

Pest Incidence and Management in CUPS

Josh McGillCUPS, Pests, Research

By Jawwad A. Qureshi and Salman Al-Shami The citrus under protective screen (CUPS, Figure 1) system is designed so citrus can grow inside screened enclosures to protect it from huanglongbing (HLB) and the Asian citrus psyllid (ACP, Diaphorina citri). ACP is the primary vector of the pathogen responsible for causing HLB, known as citrus greening disease. This vector-pathogen combination is …

CRDF Reviews Audit and Analyzes Budget

Josh McGillCRDF, Research

The Citrus Research and Development Foundation (CRDF) board of directors gathered for its August meeting. Its first order of business was a review of an auditor’s report. “I’m pleased to report there were no findings. A clean audit is always good news,” said Rick Dantzler, chief operating officer of CRDF. The board dedicated time to the budget, analyzing funds available …

California CRaFT Project Targets Psyllids

Josh McGillCalifornia Corner, Psyllids, Research

All commercial citrus producers in California are invited to apply for participation in the Citrus Research Board’s (CRB) California-focused Citrus Research and Field Trials (CA-CRaFT) project. The overarching goal of CA-CRaFT is to demonstrate the effects of additional mitigations on Asian citrus psyllid control within commercial citrus groves across the various citrus-growing regions in California. The project is supported by …

study

Liberibacter Relative Mutating Rapidly

Josh McGillBrazil, Diseases

A bacterial species closely related to citrus greening disease is rapidly evolving its ability to infect insect hosts and possibly plants. The newly identified species belongs to Liberibacter, a family of bacteria known to infect several economically important crops. There are nine known Liberibacter species, including three that are associated with citrus greening.  Citrus greening, also known as huanglongbing or …

Impact of HLB on Fruit Growth and Retention

Josh McGillFruit Drop, HLB Management

By Tripti Vashisth and Mary Sutton Citrus trees affected by huanglongbing (HLB) consistently have small fruit and low fruit numbers at harvest. The low fruit numbers are largely attributed to the increased rates of preharvest fruit drop that accompany HLB. Small fruit is more likely to drop during this preharvest period, suggesting a link between fruit size and retention. To …

California Growers Show Strong Support for Citrus Research Board

Josh McGillCalifornia Corner, Research

California citrus growers recently voted by a large margin to continue their support of the Citrus Research Board (CRB) in a state-mandated referendum. The recently concluded referendum, which must be held every five years, was conducted by the California Department of Food and Agriculture (CDFA). A majority of eligible citrus producers voted in the referendum. Their support was nearly unanimous …

California HLB Quarantine Areas Expanded

Josh McGillCalifornia Corner, HLB Management, Regulation

Federal and state officials in late June expanded the areas quarantined for huanglongbing (HLB, also known as citrus greening), caused by Candidatus Liberibacter asiaticus, in California. The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) took the action in cooperation with the California Department of Food and Agriculture (CDFA). APHIS added portions of Los Angeles, Orange, Riverside …

psyllids

Second CLas-Positive Psyllid Sample Found in California Grove

Josh McGillCalifornia Corner, Pests, Psyllids

An Asian citrus psyllid (ACP) sample confirmed positive for Candidatus Liberibacter asiaticus (CLas) — the bacteria that causes huanglongbing (HLB) — was collected from a commercial citrus grove in the Pauma Valley area of California’s San Diego County. This confirmation marks the first CLas-positive ACP found in a commercial grove in San Diego County and only the second grove detection …

ACP Detection Response: ‘The System Is Working’

Josh McGillCalifornia Corner, HLB Management, Pests

County and state officials in California have been actively responding to various Asian citrus psyllid (ACP) discoveries in the Central Valley in recent weeks. Kern, Tulare and Fresno counties have all reported an ACP detection over the last month. The Citrus Pest and Disease Prevention Division (CPDPD) has been implementing delimitation protocols and necessary treatment programs. CPDPD Director Victoria Hornbaker …

Use Physical Barriers for Root Health

Josh McGillIPCs, Root health, Tip of the Week

By Larry Duncan Citrus trees in Florida soils infested with diaprepes root weevil (Diaprepes abbreviatus) or sting nematode (Belonolaimus longicaudatus) frequently contend with devastating damage to their root systems. This is made even worse by root loss due to huanglongbing (HLB) disease. Where soil conditions are conducive to the insect or nematode, it is very difficult to prevent major economic …

High Summer Temperatures Take a Toll on Trees

Josh McGillResearch, Weather

By Anirban Guha and Christopher Vincent A quick body temperature test is common these days before entering many workplaces, hospitals and clinics due to the ongoing COVID-19 pandemic. The purpose is to screen people for fevers, usually with a non-contact infrared thermometer. Measurement of plant body temperatures also has become common for many field crops, not to screen for infectious …

citrus greening

Representatives Ask for HLB Pesticide Approval

Josh McGillLegislative, Pesticides

U.S. Representatives Kat Cammack and Al Lawson led members of the Florida congressional delegation to ask the U.S. Environmental Protection Agency (EPA) for expeditious approval of Vismax, a biochemical pesticide for HLB. A letter from the representatives asks the EPA to rapidly approve the use of Vismax in preventing HLB so the industry may access this product before the start …

Pests, Pathogens and IPCs

Josh McGillIPCs, Pests, Research

By Lauren Diepenbrock, Megan Dewdney, Fernando Alferez, Jawwad Qureshi and Ozgur Batuman Individual protective covers (IPCs) are becoming commonplace in citrus production to support the development of young trees after planting. IPCs are made of fine mesh and are intended to keep Asian citrus psyllids (ACP) off young plants. Because ACP can transmit the pathogen that causes citrus greening/huanglongbing, preventing …

florida

Integration of Nutrition and Crop Protection Products

Josh McGillNutrition, Pesticides, Research

By Davie Kadyampakeni and Evan Johnson In the era of citrus greening disease (huanglongbing, HLB), maintaining optimal nutrition and disease/pest management strategies is critical for avoiding adverse effects on tree performance. Use of the right fertilization rate, timing and placement are important for optimal citrus production. In a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) research study, …

Research Update: Stable Antimicrobial Peptide

Josh McGillPeptides, Research

By Hailing Jin Research on the effectiveness of a novel stable antimicrobial peptide (SAMP) identified from the Australian finger lime (Microcitrus australasica) to fight huanglongbing (HLB) continues in a multistate initiative involving 1,500 citrus trees. Although the pandemic has impacted the progress of the research, work has steadily continued and expanded.  Researchers at the University of California, Riverside and University …

Phosphorus Recommendations and Soil pH Amendments

Josh McGillHLB Management, Nutrition, Soil Improvement

By Kelly T. Morgan and Davie Kadyampakeni Most information provided in the 2020 3rd edition of Nutrition of Florida Citrus Trees is still sound for healthy citrus trees under Florida production conditions. Past information on nutrients, application methods, leaf and soil sampling, and irrigation scheduling are also effective for management of huanglongbing (HLB)-affected trees. However, research conducted since HLB was …

Comparison of ACP/HLB Management Tools for Citrus Resets

Josh McGillDiseases, HLB Management, Research

By Lauren Diepenbrock, Megan Dewdney, Christopher Vincent and Davie Kadyampakeni As the threat of potential shutdowns loomed in March 2020, a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) team put the final plants in the ground, individual protective covers (IPCs) on trees, and kaolin and pesticide applications on a 2.7-acre planting at the Citrus Research and Education …

Growers Needed to Aid Development of HLB Tool

Josh McGillHLB Management, Research

Excelsior Aerospace Corporation announced it is pursuing funding from the U.S. Department of Agriculture (USDA) to build a free tool that can rapidly detect, track and manage huanglongbing (HLB) disease. “On one end, our tool would serve growers in states such as Texas and California to detect early symptoms of ACP (Asian citrus psyllid) and HLB infection and take measures …