pgrs

PGRs: Multipurpose Tools for Citrus Improvement

Daniel CooperPGRs, Tip of the Week

By Tripti Vashisth Canopy health of HLB-affected citrus has been directly related to disease severity, fruit drop and overall fruit production. Some success has been found with the use of certain plant growth regulators (PGRs) such as gibberellic acid (GA) and 2,4-dichlorophenoxyacetic acid (2,4-D) to achieve healthier trees with reduced fruit drop and increased production. HLB MANAGEMENT Application of these …

Taking Available Tools to the Grove

Tacy CalliesHLB Management

The quest for long-term solutions to HLB is well underway. Technology like CRISPR is being developed to introduce tolerance or resistance to HLB. Conventional breeding also is seeking rootstocks and varieties that can resist the disease. In the meantime, growers are reminded to utilize available tools that help trees remain productive in an HLB environment. During the August Citrus & …

Bud Advisories Help Growers Time Psyllid Sprays

Tacy CalliesIndustry News Release

The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) is reminding citrus growers that flower bud advisories are now being issued. The UF/IFAS advisories can help growers determine when to spray for HLB-spreading Asian citrus psyllids and when to stop spraying in an effort to protect pollinating bees. Tripti Vashisth, a UF/IFAS associate professor of horticultural sciences, will …

HLB Treatments ‘A Mixed Bag of Results’

Josh McGillHLB Management

A variety of treatments Florida citrus growers are using for HLB have so far produced mixed results, according to observations reported by Highlands County Citrus Growers Association (HCCGA) President Aaron Nelson. In a recent association newsletter, Nelson wrote that many are anxious to see harvest data showing what effects the treatments have had over the past year. The treatments he …

All In With Trunk Injection

Josh McGillHLB Management, planting

Some Florida citrus growers decided to start slowly with trunk injection of oxytetracycline (OTC), treating only a small portion of their acreage. Others took a wait-and-see approach, hoping to learn from their peers’ experiences. But Wheeler Farms went all in, treating 100% of their trees with trunk injection. “What we were doing was not working, so we needed to try …

$5 Million Awarded to UF/IFAS for HLB Research

Josh McGillHLB Management, Research

The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) has been awarded five federal grants totaling more than $5 million to control HLB. The grants are from the U.S. Department of Agriculture’s National Institute of Food and Agriculture (NIFA).   HLB is caused by the bacterium Candidatus Liberibacter asiaticus (CLas). The Asian citrus psyllid can transmit CLas into a …

Combine Plant Growth Regulators for Most Benefit

Josh McGillCitrus Expo, PGRs

Using the plant growth regulators (PGRs) gibberellic acid (GA), 2,4-D and cytokinin in combination can maximize the benefit for HLB-affected trees, researcher Tripti Vashisth reported recently. The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) associate professor of citrus horticulture and production works at the Citrus Research and Education Center in Lake Alfred. She discussed the benefits of …

Treat HLB Trees With the Right PGR at the Right Time

Josh McGillHLB Management, PGRs, Research

By Tripti Vashisth, Wesley Webb and Taylor Livingston As trees become symptomatic for HLB, leaves experience an imbalance of plant hormones. This hormonal imbalance exacerbates HLB symptoms and can lead to more stem dieback, poor vegetative growth and fruit drop. This ultimately leads to reduced bearing wood, resulting in yield losses and tree decline. Thus, the use of growth-promoting hormones …

Prevent and Recover From Hurricane Damage

Josh McGillhurricane, Tip of the Week

By Christopher Vincent, Tripti Vashisth and Gillian Zeng Michalczyk Hurricane Ian harmed citrus trees in much of Florida, especially in areas where sweet oranges are grown. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers are tracking the health of trees in groves around the state as they struggle to recover. Fall applications of gibberellic acid before the storm …

Recovery Will Require a Multipronged Management Program

Josh McGillHLB Management, hurricane, Production

By Michael Rogers The 2022–23 Florida harvest season is now behind us. Yield losses magnified by the weather events this past season position the next couple of years as “make or break” for many growers. The lingering effects of hurricane Ian will impact next season’s crop as trees continue to recover and balance out canopy regrowth with fruit production. Despite …

Build Resilience in HLB-Affected Hamlin Trees

Josh McGillHLB Management, Tip of the Week

By Taylor Livingston and Tripti Vashisth Fighting HLB alongside weather disasters like freezes and hurricanes is leaving growers with little options for sustaining yields. The Hamlin sweet orange variety is known for higher susceptibility to HLB symptoms which cause rapid tree decline, including increased pre-harvest fruit drop and canopy loss. Production strategies that target fruit drop and canopy health improvement …

Repurposing Tools to Tackle HLB

Josh McGillHLB Management

By J. Scott Angle, jangle@ufl.edu, @IFAS_VP The hurricane-battered harvest numbers don’t show it, but we’re in a much better place in developing scientific solutions for managing HLB than we were a year ago. That’s because our scientists have discovered that tools invented to solve other problems can help address your one big problem. GIBBERELLIC ACIDFor example, gibberellic acid (GA) has …

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, …

Determine Tree Health With Canopy Assist

Josh McGillHLB Management, Technology, Tip of the Week

By Amit Levy and Tripti Vashisth Many Florida citrus growers are currently injecting oxytetracycline, spraying gibberellic acid (GA) or treating trees with enhanced nutrition. A new program offered by the University of Florida Institute of Food and Agricultural Sciences (UFIFAS) Citrus Research and Education Center (CREC) can help growers determine if these treatments are improving tree health and leading to …

Seminar Speakers Share Latest Citrus Research

Josh McGillEducation, Events, Research

The citrus session at the Florida Grower Citrus Show started off with a special award acknowledgement by Ron Cave, director of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Indian River Research and Education Center (IRREC). Cave recognized Pasco Avery for his induction into the 2022 class of the IPM Hall of Fame from the Southern IPM …

Cytokinin Studied for Citrus Health Benefits

Tacy CalliesHLB Management, PGRs, Research

Tripti Vashisth, University of Florida Institute of Food and Agricultural Sciences associate professor, has been leading the research on how plant growth regulators (PGRs) can improve the health of HLB-infected trees. She’s conducted extensive research on the use of gibberellic acid. But she has recently begun to study another hormone, cytokinin. She gave an update on this work during the …

Trunk Injection Inspires Interest in Planting

Josh McGillEvents, HLB Management

The Florida Citrus Growers’ Institute, presented by the University of Florida Institute of Food and Agricultural Sciences, was held in Avon Park on April 4. The annual educational event drew a good crowd of growers and allied industry. After nearly two decades of fighting HLB, and more recently fallout from hurricanes, those in attendance expressed a renewed sense of optimism …

Lessons Learned From HLB as an Immune-Mediated Plant Disease

Josh McGillHLB Management, Research

By Nian Wang How the huanglongbing (HLB) pathogen Candidatus Liberibacter asiaticus (CLas) causes damage to infected citrus trees has been widely debated. A recent study demonstrates that HLB is an immune-mediated plant disease (Ma et al., 2022). It was discovered that CLas infection of citrus stimulates systemic and chronic immune response in phloem tissues, including reactive oxygen species (ROS) production, …

Citrus Institute: One-Stop Learning Opportunity for Growers

Josh McGillEducation, Events, Tip of the Week

By Ruth Borger Keeping up with the latest news and research findings that impact how growers can successfully produce citrus in the HLB era can be an overwhelming task. Tracking down the right information at the right time for the changing conditions that face citrus growers takes time, effort and persistence. University of Florida Institute of Food and Agricultural Sciences …

Lessons From Hurricane Ian Will Help Growers

Josh McGillhurricane, Survey

Researchers will assess 20 to 30 Florida citrus groves impacted by 2022’s Hurricane Ian to learn lessons that will help growers in the future. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers Christopher Vincent and Tripti Vashisth and their teams will conduct the assessment. The research will be funded by a $280,000, one-year grant from the U.S. …