young trees

Recovering Unprotected HLB-Infected Young Trees

Daniel CooperIPCs, Tip of the Week

By Fernando Alferez and Saoussen Ben Abdallah Individual protective covers (IPCs) are now being increasingly adopted in Florida to protect newly planted citrus trees from psyllid colonization. The risk of new citrus plantings becoming infected with HLB is especially high, as young trees flush more frequently and attract more psyllids. However, the adoption of IPCs does not occur in all …

Citrus canker

Reduce Fruit Drop From Citrus Canker

Daniel CooperDiseases, Fruit Drop, Tip of the Week

By Megan Dewdney Citrus canker can contribute significantly to the loss of fruit prior to harvest. As bloom begins in Florida, it is time to finalize management plans for foliar diseases. For many growers, very aggressive canker management programs are no longer a possibility, however, some management is important. Citrus canker susceptibility of young fruitlets usually starts at the end …

virus

Stay Vigilant About Virus Threat

Daniel CooperDiseases, Tip of the Week

By Ozgur Batuman and Amit Levy Citrus yellow vein clearing virus (CYVCV) was first reported on lemon and sour orange trees in Pakistan in 1988. Since then, the disease has been primarily restricted to Asian countries. However, CYVCV was more recently detected in dooryard citrus in California in 2022. While there is no indication that the virus is present in …

HLB-affected trees

Frequent Irrigation Is Critical for HLB-Affected Trees

Daniel CooperHLB Management, Irrigation, Tip of the Week

By Tripti Vashisth and Mary Sutton HLB-affected trees have small and weak root systems. These trees often experience water and nutrient deficit. However, not all HLB-affected trees experience the same impact. Trees with severe HLB symptoms will have higher root loss and water deficit than trees with mild HLB symptoms. The water deficit exacerbates during spring, which is often the …

weather

Foliar Disease Watch in Florida

Daniel CooperDiseases, Tip of the Week

By Megan Dewdney Spring is the time to start thinking about foliar disease management in Florida. Depending on the type of citrus being produced and the market destination, different diseases will be important. POSTBLOOM FRUIT DROP The disease that affects all citrus, particularly oranges, is postbloom fruit drop (PFD). This disease is highly dependent on the weather during bloom. Currently, …

brassinosteroids

When to Apply Brassinosteroids to Improve Valencia Fruit Quality

Daniel CooperPGRs, Tip of the Week

By Fernando Alferez and Divya Aryal Like the work being done with Hamlin sweet orange, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers are studying the effect of brassinosteroids (BRs) on the internal maturation of Valencia sweet orange fruits. The conditions of the treatments are the same as in Hamlin: A treatment of 186 milliliters of BR …

herbicide tolerance

Strategies for Managing Herbicide Tolerance

Daniel CooperTip of the Week, weeds

By Ramdas Kanissery Tackling herbicide tolerance in weeds is a critical aspect of effective weed control in citrus groves. It helps prevent both current and future weed management challenges. Herbicide tolerance occurs when certain weed species naturally survive and reproduce after herbicide treatment. Unlike herbicide resistance, where genetic changes allow weeds to survive and spread, herbicide tolerance doesn’t involve any …

nutrient management

Rejuvenate HLB Trees With Precision Nutrient Management

Daniel CooperNutrition, Tip of the Week

By Meryam Manzoor, Jamie D. Burrow, Taylor Livingston and Tripti Vashisth Effective nutrient management and accurate nutritional analysis are critical for tree growth and maximum yield. Historically, nutrient management for healthy citrus trees involved annual leaf sampling from July to August, with subsequent fertilization plans based on a single nutrient analysis. Almost all commercial citrus groves in Florida are affected …

oxytetracycline

Oxytetracycline Efficacy Impacted by Exposure to Field Conditions

Daniel CooperHLB Management, Tip of the Week

By Lauren Fessler Mathews, Sanju Kunwar, Ana Redondo and Ozgur Batuman Based on numerous research studies conducted by scientists at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), it has been proven that injections of oxytetracycline (OTC) can help to alleviate symptoms caused by huanglongbing (HLB) disease. This treatment is now widely practiced and crucial for preventing …

IPCs

Combine IPCs and Brassinosteroids to Prolong Young Tree Health

Daniel CooperIPCs, Tip of the Week

By Fernando Alferez and Saoussen Ben Abdallah The risk of citrus plantings to become infected with HLB is especially high for young trees, which flush frequently and attract more psyllids than mature trees. Individual protective covers (IPCs) are now being increasingly adopted to protect newly planted citrus trees from psyllid colonization. However, even though IPCs effectively protect young trees from …

pest management

Plan Your 2025 Pest Management

Daniel CooperPest Management, Pests, Tip of the Week

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 …

two

Two New Early-Season Sweet Oranges for Florida Growers

Daniel CooperTip of the Week, Varieties

By Manjul Dutt, Sheetal Ramekar and Gary England Developing new citrus cultivars, whether through conventional breeding or genetic engineering methods like transgenics or CRISPR is potentially the most viable long-term strategy to combat huanglongbing (HLB). Identifying potential survivor trees — citrus trees that exhibit disease tolerance in areas with endemic HLB — can also serve as a useful strategy for …

controls

Controls Needed to Effectively Evaluate Treated Trees

Daniel CooperHLB Management, Tip of the Week

By Ute Albrecht, Gabriel Pugina and Caroline Tardivo Two years have passed since trunk injection of oxytetracycline (OTC) was approved for HLB management in Florida. Many growers have adopted this technology. While most reported positive responses, others did not. The plant physiology team at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Southwest Florida Research and Education …

fertilizer

Fertilizer Considerations for HLB-Affected Citrus

Daniel CooperNutrition, Tip of the Week

By John M. Chater and Davie Kadyampakeni Soil fertility is a keystone to a productive citrus grove in Florida. In the era of huanglongbing (HLB), the need to fine-tune soil fertility takes on even more importance. The sandy soils found in citrus-growing regions of the state are great for drainage to reduce flooding stress of citrus trees in many cases, …

spot

Improve the Success of Spot Sprays

Daniel CooperTip of the Week, weeds

By Ramdas Kanissery Spot application of post-emergent herbicides provides an effective solution for controlling weeds that are missed by standard maintenance herbicide programs in citrus groves (Figure 1, left). This method is also helpful for targeting weeds in areas that herbicide boom sprayers can’t reach, like those growing near the trees (Figure 1, right). Here are some key tips to …

residential

Improving ACP and HLB Control in Residential Settings

Daniel CooperHLB Management, Psyllids, Tip of the Week

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 …

flowering

How to Handle Extended Flowering in HLB Trees

Daniel CooperProduction, Tip of the Week

By Tripti Vashisth University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) flower bud induction advisories for 2024–25 started on Nov. 25. The advisories will be posted bi-weekly until March 2025. The goal of the advisories is to provide growers and production managers with a complete overview of flowering prediction. Every advisory will aim to deliver recommendations for that …

flame

New Flame Grapefruit Selection Offers Improved HLB Tolerance

Daniel CooperGrapefruit, Tip of the Week, Varieties

By Manjul Dutt, Sheetal Ramekar and Gary England The grapefruit was created by chance from a cross between a pummelo and a sweet orange. It was first discovered in Barbados in the 18th century. All the commercially sold grapefruits today trace their roots back to the Duncan variety of grapefruit. Cultivars existing today were developed through natural and induced mutations …

Hamlin

Apply Brassinosteroids to Improve Hamlin Brix

Daniel CooperHLB Management, PGRs, Tip of the Week

By Fernando Alferez and Divya Aryal Brassinosteroids (BRs) are a class of plant growth regulators with several effects on plant growth and development. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) work in the last few years has shown that BR treatments may influence internal maturity in Hamlin sweet orange if performed at the right time. Research has …