By Larry Duncan Monitoring population levels of plant parasitic nematodes and phytophthora is best done in springtime prior to the rainy season. Peak population density of the citrus nematode (Tylenchulus semipentrans) occurs at that time, and the accuracy of sample results increases with population density. The sampled population levels of this nematode and those of Phytophthora spp. can be compared …
Predatory Mites in Citrus Under Protective Screen
By Emilie Demard and Jawwad Qureshi Managing the Asian citrus psyllid (ACP), a vector of huanglongbing (HLB), is critical for reducing disease incidence and improving tree health. Growing citrus under screened structures, referred to as citrus under protective screen (CUPS), protects trees from ACP and HLB. CUPS provides an opportunity to produce premium-quality fresh fruit by preventing psyllids and HLB …
Could Finger Limes Be Florida’s Hero?
The Australian finger lime, a citrus relative, could be a new specialty crop for Florida citrus growers. Traditionally, finger limes have remained rare in the United States, grown few and far between. However, the fruit’s unique tolerance to HLB is becoming increasingly attractive to Florida growers. Manjul Dutt, research assistant scientist at the University of Florida Institute of Food and …
Florida Growers Wanted for Rootstock Trials
The Citrus Research and Development Foundation (CRDF) is establishing a new project to evaluate the most promising citrus rootstocks in grower field trials. The rootstock trials are projected to be planted in the spring or summer of 2022. The goal will be to identify plant material with the traits needed for growers to realize the highest possible pound solids per …
HLB Spending Summarized
Citrus Research and Development Foundation (CRDF) Chief Operating Officer Rick Dantzler on Feb. 23 detailed CRDF spending on efforts to solve HLB. According to Dantzler, the Florida-based organization spent $140.7 million between its formation in 2009 and 2020. The vast majority of CRDF’s focus has been on HLB. Dantzler’s report came moments after University of Florida (UF) Institute of Food …
Improving Root Health in the Era of HLB
Developing and maintaining a healthy root system is crucial for establishment and long-term productivity of citrus trees. The presence of HLB can greatly complicate citrus root-health management. The infection causes severe damage to fibrous roots that amplify the detrimental effects caused by other root pests and pathogens, such as phytophthora root rot. Due to HLB’s widespread presence throughout Florida, root-health …
New Solution for Fruit Drop?
Fruit left on the ground is a waste for growers and consumers alike, and Florida’s citrus industry certainly cannot afford to leave any fruit behind. Citrus fruit drop before harvest has been particularly challenging during the 2020-21 Florida growing season. That is why Fernando Alferez, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) citrus horticulturist, is researching strategies …
Stem Pitting Disease Caused by Citrus Tristeza Virus
By Amit Levy, Peggy Sieburth and Ozgur Batuman When we hear or read about citrus tristeza virus (CTV), we usually think about the decline of sweet orange or grapefruit trees on sour orange rootstocks. However, there are other diseases caused by different isolates of the virus. One of these diseases is stem pitting, mostly caused by the VT isolate of …
Georgia Owari Rootstock Trial Update
Ongoing citrus rootstock trials being conducted by the University of Georgia (UGA) hold promise for Georgia’s growing citrus industry. Jake Price, UGA Extension agent and Lowndes County Extension coordinator, has produced six local citrus rootstock/variety trials with varying objectives. The oldest trial, planted in 2014, is growing Owari satsuma trees on standard and new trifoliate hybrid rootstocks. Each year, as …
UF/IFAS VP Scott Angle on HLB Efforts
Florida’s citrus growers are counting on research to help sustain what’s left of an industry decimated by huanglongbing (HLB). The disease remains a focal point of research at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS). Scott Angle, vice president for agriculture and natural resources at UF/IFAS, understands the ramifications if improved HLB management options aren’t available …
Georgia Trials Offer Rootstock Choices
Ongoing citrus rootstock trials being conducted by University of Georgia (UGA) Cooperative Extension in Lowndes County hold promise for increased yields, improved fruit quality and greater disease resistance. Jake Price, UGA Extension agent and Lowndes County Extension coordinator, has six local citrus rootstock/variety trials with varying objectives. The trees are custom-produced by U.S. Department of Agriculture (USDA)-certified citrus nurseries in …
Georgia Citrus Pest and Disease Update
As the Georgia citrus industry continues to grow and prosper, growers should be aware of the potential signs of citrus pests and diseases that could be looming in their groves. Bill Barber, Certified Crop Advisor and owner of Barber Ag Services, delivered a presentation during the 2021 virtual Southeast Regional Fruit and Vegetable Conference. He addressed pests and diseases presently …
Choosing a Lemon Rootstock
By Kim D. Bowman Lemons are a relatively small part of the Florida citrus crop. But with more than 317,000 lemon trees propagated in Florida nurseries over the past two years, lemons are clearly gaining increasing interest from growers trying to find a crop that is easier to grow and with a quick return on investment. As is the case …
Freeze Protection Measures for Citrus
Multi-county citrus Extension agent Chris Oswalt discussed historical and current freeze protection measures in a virtual Dec. 22 OJ Break. PASSIVE MEASURESSome cold-protection measures are taken well in advance of freezes; Oswalt referred to them as passive measures. They include grove site selection, crop selection and cultural practices. One site selection consideration is planting groves at higher elevations, which are …
Root Bacteria Could Help Defeat HLB
A team led by the University of California, Riverside (UCR) is looking at tiny underground microorganisms for a way to prevent a huge problem — huanglongbing (HLB), a disease with no cure that has decimated citrus orchards worldwide. “Often times, it is thought of as an above-ground disease of the fruits, leaves and stems,” said Caroline Roper, plant pathology professor …
John Gose: Serving Youth and Industry
Ray Royce readily acknowledges grower and nurseryman John Gose’s many contributions to the Florida citrus industry, including serving “on way too many advisory committees to list.” Gose has even been president of the Highlands County Citrus Growers Association, where Royce is executive director. PROGRAM LEADERSHIPBut it’s not Gose’s work with growers that most impresses the association executive. “I always think …
Research Update on Individual Protective Covers
By Fernando Alferez, Susmita Gaire, Ute Albrecht, Ozgur Batuman, Jawwad Qureshi and Mongi Zekri It has been nearly three years since the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) started its studies on individual protective covers (IPCs). The objective of this study is to evaluate the feasibility of IPCs as a strategy to prevent HLB infection of …
Five Years of Fresh Fruit Production in CUPS
By Arnold Schumann, Laura Waldo, Napoleon Mariner and Timothy Ebert According to the U.S. Department of Agriculture (USDA), Florida grapefruit production for the 2019–20 season was only 12 percent of the production recorded in 2003–04, prior to the arrival of huanglongbing (HLB) disease in the state. A major goal of the University of Florida Institute of Food and Agricultural Sciences …
Genome Sequencing and Other UF Research
Michael Rogers discusses the importance of the recent sequencing of the trifoliate orange genome by University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers and others. He also tells how growers can learn more about UF/IFAS research funded by the Florida Legislature. Rogers is director of the UF/IFAS Citrus Research and Education Center (CREC) in Lake Alfred and …
CRDF Addresses Plant Improvement, Budget
Citrus Research and Development Foundation (CRDF) directors recently received an update on planned rootstock field trials and discussed the organization’s budget, CRDF Chief Operating Officer Rick Dantzler reported. ROOTSTOCK TRIALSThe new rootstock trials will be overseen by CRDF’s Select Committee on Plant Improvement, which met on Oct. 22 with citrus grower John Gose as chairman. Dantzler said the field trials …





























