The California Department of Food and Agriculture (CDFA) recently announced the expansion in Orange County of an emergency program for HLB and the Asian citrus psyllid (ACP) that spreads the disease. The expansion follows confirmation throughout January of the causative bacterial agent of HLB in plant tissue and/or ACP in Anaheim, Costa Mesa, Garden Grove, Irvine, Mission Viejo, Orange, Santa …
HLB Confirmed in Arizona for First Time
HLB was recently confirmed for the first time in Arizona, first in an Asian citrus psyllid (ACP) and then in another ACP and citrus plant tissue. The Arizona Department of Agriculture (AZDA) reported the details. On Dec. 16, 2024, agriculture inspectors collected ACP and plant tissue samples from a residential citrus tree in Nogales. The collections were made during a …
Survey Shows Popular Scions and Rootstocks
The Florida Citrus State of the Industry Survey seeks input from growers on key issues affecting their groves. The survey has been conducted for many years, has tracked the trajectory of HLB and reported on production practices. While not a scientific survey, it has reflected general trends over the years. Last month, we published results on trunk-injection therapy and the …
Weathering the HLB Storm
Specialty crop growers might be aware of the disease sweeping through Florida’s citrus industry. Its impact has been tremendous and has tested the survival of the state’s signature crop. This year will mark the 20th anniversary of the official confirmation of citrus greening disease (also known as huanglongbing or HLB) in Florida. In the past two decades, the state’s output …
Plan Your 2025 Pest Management
By Lauren Diepenbrock Pest management is a year-round challenge in Florida citrus. With the warm climate, pests are at the ready as soon as plant resources are available to them. With knowledge of invertebrate biology in relation to tree phenology, growers can develop plans to protect fruit and maintain productive citrus trees. HIGHLY PROBLEMATIC PESTS Populations of some highly problematic …
Costa Rican Orange Production
The U.S. Department of Agriculture Foreign Agricultural Service (USDA FAS) expects Costa Rican orange production to increase approximately 11% in 2024–25, to 250,000 metric tons. Production in 2023–24 was lower than expected at 225,000 metric tons as a result of erratic rainfall patterns associated with the El Niño weather phenomenon. The area planted in oranges is expected to remain unchanged …
CUPS Success Rate a Relief for Researcher
The success of citrus under protective screen (CUPS) in protecting Florida citrus from citrus greening, also known as huanglongbing or HLB, was not surprising to Arnold Schumann. The professor of soil fertility and water quality at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center is thankful research had yielded a temporary solution …
Improving ACP and HLB Control in Residential Settings
By Romain Exilien and Xavier Martini Residential gardens serve as reservoirs for Asian citrus psyllids (ACP) and citrus greening disease (also known as huanglongbing or HLB) due to unmanaged citrus trees. The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) conducted a survey to assess residents’ needs regarding ACP and HLB management. The survey examined their current control …
California HLB Quarantine Expanded
Agricultural officials recently expanded the areas in California quarantined for citrus greening disease [also known as huanglongbing (HLB)], which is spread by Asian citrus psyllids. The quarantined area in Orange and Riverside counties was increased by a total of approximately 31 square miles. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) in cooperation with the …
Ongoing Research Shows the Promise of Trunk-Injection Therapy
Trunk injection of oxytetracycline (OTC) has been the center of attention in Florida citrus for the past two years since the Environmental Protection Agency registered formulations of the material for use. But experience with antibiotics in Florida citrus is not new. That was part of the message Lukasz Stelinski delivered to attendees of the Citrus & Specialty Crop Expo in …
CUPS Expensive but Beneficial
The benefits of implementing citrus under protective screen (CUPS) could be major for growers in the cold-hardy region. But they first must overcome the major limiting factor associated with the system — its cost. Arnold Schumann, a professor of soil fertility and water quality at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education …
Post-Hurricane Pest Management
University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researcher Lauren Diepenbrock recently offered post-hurricane observations and management suggestions for some insects and snails. Diepenbrock is an assistant professor at the Citrus Research and Education Center. BULIMULUS SNAILS Related Bulimulus snail species have been found to lay eggs in the fall after major rain events. Both small and larger …
Australian Lime Interstocks to Combat HLB
By Ozgur Batuman, Sanju Kunwar and Ana Redondo In a promising effort to protect citrus from huanglongbing (HLB), University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers are exploring the potential of Australian lime as an interstock graft for Valencia scions with Swingle rootstock. The interstock technique uses various limes, known for their natural HLB-tolerant peptides, between the …
Top Pruning Evaluated as HLB Strategy
A Brazilian study evaluated the effects of top pruning on orange trees located on the edges of an orchard as part of an HLB management strategy. The pruning was an attempt to attract the HLB-spreading psyllid from external areas to the orchard edges and control it, reducing its dispersion into the orchard. Fundecitrus and Embrapa Cassava and Fruits conducted the …
Immediate Response Required When Managing HLB
The first chore for growers in the cold-hardy citrus region when managing citrus greening is scouting for the disease and its vector, the Asian citrus psyllid. The next step is prompt removal of any trees infected with the disease, says Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist. “At this point, we think greening is still …
Brassinosteroids Help Trees After IPC Removal
Associate Professor Fernando Alferez and his team at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) learned several years ago that individual protective covers (IPCs) protect newly planted trees from HLB. They do that by excluding the Asian citrus psyllids (ACP) that spread the devastating citrus disease. But multi-county citrus Extension agent Mongi Zekri noted that IPCs …
Factors to Consider When Planting a New Grove
Growers have numerous things to think about when planting a new grove. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) citrus genetic improvement specialist John Chater discussed this topic during a recent Citrus & Specialty Crop Expo presentation. Following are highlights from his talk on establishing new varieties in a new citrus grove. PESTS AND DISEASES Soilborne pests …
Heat and HLB Hurting Brazil’s Production
Brazil’s citrus crop is suffering this season, according to Franklin Behlau, a senior researcher for Fundecitrus. That was the focus of a recent presentation he provided at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center in Lake Alfred. “Things have changed in Brazil this season,” Behlau said. “We are a little behind …
IPCs Aid Trees and Fruit After Removal
Individual protective covers (IPCs), used primarily to protect young citrus trees from HLB-spreading Asian citrus psyllids, have become ubiquitous in Florida citrus groves in recent years. New University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) research shows the trees grown under the IPCs also grow well for a few years after growers remove the bags. Growers typically remove …
International HLB Conference Focused on Grower Solutions
This spring, the seventh International Research Conference on Huanglongbing (IRCHLB) was held in Riverside, California. The inaugural event was held in 2008 and funded by a grant from the U.S. Department of Agriculture (USDA) National Institute of Food and Agriculture. USDA researcher Tim Gottwald and University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) professor Jim Graham founded the …