By Fernando Alferez Five years of University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) data in trials across the state have shown that individual protective covers (IPCs) are effective in preventing HLB until they are removed. This has been shown in sweet orange varieties such as Valencia and Hamlin. In these varieties, it has been demonstrated that the …
Gibberellic Acid Applications: Day vs. Night
By Alessandro Franco, Faisal Shahzad and Tripti Vashisth Gibberellic acid (GA) is one of the most commonly used plant growth regulators which affects flowering, fruit and vegetative growth. Multiple monthly GA foliar applications have reduced preharvest fruit drop and increased yield in huanglongbing (HLB)-affected sweet oranges. The potential impact of these findings is huge for commercial citrus production. However, there …
CUPS Irrigation and Fertilization for Grapefruit
By Rhuanito S. Ferrarezi and Mark A. Ritenour Citrus under protective screen (CUPS) is a modern production system that excludes the Asian citrus psyllid and, consequently, the devastating disease citrus greening (huanglongbing or HLB) from plants cultivated in screenhouses. A recent study investigated the effect of different irrigation management strategies on fruit yield and quality of grapefruit grown in CUPS. …
Don’t Miss the Florida Grower Citrus Show
By Ron Cave In 1946, leaders with the University of Florida and the Indian River Citrus League ascertained the need for an event where growers, the trade organization and researchers might network and attend educational sessions presented by scientists. So began the first-ever Indian River Citrus Seminar, which would later become the Florida Grower Citrus Show. In the 1960s, Florida’s …
Should Florida Growers Be Worried About Lime Swallowtail?
By Lauren Diepenbrock Recently, several articles have highlighted a potential new threat to the citrus industry in Florida, the lime swallowtail. While it is true that this pest has been found in residential citrus plantings in Key West, it is unlikely that lime swallowtail will have much of an impact, if any, on Florida’s commercial citrus industry. Lime swallowtail is …
Citrus Institute: One-Stop Learning Opportunity for Growers
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 …
Citrus Industry Impacts Florida’s Economy
By Julio Cruz, João-Pedro Ferreira and Christa Court Many Florida citrus growers are under stress due to disease and extreme weather events. Citrus growers often request financial or other types of support from local, state and federal governments due to such situations. Understanding and communicating how the citrus industry supports economic activity throughout the state, even outside of the industry …
Top 10 Best Practices for Trunk Injection
By Ute Albrecht Replicated field studies have demonstrated positive effects of oxytetracycline administered by trunk injection to manage HLB. In October 2022, a 24(c) special local need label was approved that allows the use of this technology in Florida, and final clearance was given in January. When practicing trunk injection, it is important to do so properly and to be …
Revised Approach to Reduce ACP Management Costs
By Lukasz Stelinski Vector control is considered a basic component of HLB management even under high disease incidence scenarios. A recent study compared the effects of three different economic thresholds (ET-0.2, ET-0.5 and ET-1.0) and one calendar-based application schedule on the incidence of Asian citrus psyllid (ACP) and beneficial species in plots of commercially grown citrus. The study also examined …
Irrigation Guidelines for Growers
By Ajia Paolillo As the season moves from winter to spring, the irrigation requirements of citrus trees change. Typically, February through May is the drier time of year in Florida with low rainfall amounts in most areas. However, during this period, the trees are actively producing leaves and flowers, setting fruit, and pumping resources to the growing fruit during cell …
OLL Sweet Oranges Producing Pre-HLB Fruit Quality
By Jude Grosser, Fred Gmitter and Maria Brenelli The new OLL (Orie and Louise Lee) series of sweet oranges (OLL-4, OLL-8 and OLL-20) are very high-quality processing sweet oranges that generally produce higher soluble solids and better juice color than Valencia. OLL trees are more vigorous than Valencia, and anecdotal evidence suggests they are slightly more HLB-tolerant than Valencia. Trees …
Prepare for the Possibility of Postbloom Fruit Drop
By Megan M. Dewdney Postbloom fruit drop (PFD) is a sporadic flower disease. It is primarily caused by the fungus Colletotrichum acutatum. While infections only occur on flowers, the fungus is present on trees throughout the year. It survives by producing resting structures on leaves and stems. How the inoculum survives multiple years between infections is still unclear. The fungus …
Sting Nematodes and IPCs
By Larry Duncan and Fernando Alferez Newly planted citrus trees are far less tolerant of pests and diseases than when mature. Sting nematode (Belonolaimus longicaudatus) was not considered a serious economic threat to Florida citrus until successive hard freezes in the 1980s caused widespread replanting of groves. Patches of stunted, declining trees caused by the irregular distribution of sting nematodes …
Planning Your 2023 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 insect and mite biology in relation to tree phenology, plans can be developed to protect fruit and maintain productive citrus trees. Populations of some highly problematic pests …
Postharvest Water Requirements for Packers
By Clara Diekman, Micah Gallagher, Taylor O’Bannon and Michelle Danyluk Compliance dates for all water associated with the Produce Safety Rule (PSR, Subpart E) has previously been delayed, pending completion of the rule. The U.S. Food and Drug Administration (FDA) announced in the fall of 2022 that postharvest water requirements in the PSR will be enforced on large farms beginning …
Get the Timing Right for Gibberellic Acid Applications
By Tripti Vashisth Since 2021, a number of Florida growers have adopted the use of gibberellic acid (GA) in their grove management programs. This widespread adoption is due to the fact that GA-treated trees show canopy rejuvenation and reduction in preharvest fruit drop, resulting in improved yields. The research on Valencia shows that the effect of GA improves over time. …
Oak Mulch Can Improve Florida Flatwoods Soil
By Lorenzo Rossi With no cure for HLB available, searching for alternative mitigation strategies is an urgent priority for a sustainable citrus industry. Interest has grown regarding the use of organic amendments to improve the fertility of Florida native soils. Although hardwood mulch applications have been demonstrated to improve both tree health and soil fertility in other fruit industries, little …
Techniques Tested on Mandarins in CUPS
By Rhuanito S. Ferrarezi and Mark A. Ritenour Two independent trials were conducted under a commercial citrus under protective screen (CUPS) system. The first trial was to investigate canopy management strategies to improve fruit yield and quality of mandarins. Canopy management is essential for CUPS since the environment stimulates vigorous vegetative growth, posing operational challenges to mechanization that can be …
It’s Time to Target Adult Asian Citrus Psyllids
By Lauren Diepenbrock Pest management is an ongoing effort in Florida citrus. Taking advantage of pest life cycles has been shown to be an effective tool for reducing populations of target pests. For many citrus growers, managing impacts of the Asian citrus psyllid (ACP), the vector of huanglongbing (HLB), is part of the annual management plan. As we enter the …
Improving Yield Safety of Glyphosate
By Ramdas Kanissery Florida citrus growers face weed management problems throughout the year because of conditions that favor rapid weed growth in groves. A weed-free tree row is desired in a citrus grove to minimize weed competition with trees. Hence, chemical weed control using post-emergent, systemic herbicides like glyphosate has become a vital production practice in the Florida citrus industry. …