By Jude Grosser, Fred Gmitter and Kim Bowman Two citrus breeding programs have identified several rootstocks that can currently be planted with confidence when combined with appropriate scions, including mid- and late-season oranges, and grown with emerging enhanced nutrition programs. These citrus breeding programs are at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education …
Nutrition and Rootstocks to Be Studied
Seventeen researchers have responded to the Citrus Research and Development Foundation’s (CRDF) request for very specific citrus nutrition research, the organization’s board of directors learned May 19. CRDF Chief Operating Officer Rick Dantzler said several advisory groups will review the proposals prior to the CRDF board choosing and funding selected proposals no later than September. The research requested by CRDF …
Advice on Picking Rootstocks
Growers who attended a recent Citrus Research and Development Foundation (CRDF) rootstock field day in Highlands County should look at similar CRDF trials when deciding what rootstocks to plant. That’s the opinion of Jim Graham, a CRDF project consultant who spoke at the event last month. The same six rootstocks with Valencia scions that are in field trials in Highlands …
USDA Releases 3 New Citrus Rootstocks
The U.S. Department of Agriculture has released three new citrus rootstocks that are available for unrestricted public use. The rootstocks are US SuperSour 1, US SuperSour 2 and US SuperSour 3. A new publication provides summary information about the new releases. Get the new publication here: Sponsored Content5 Facts About Fire Ants and How to Control ThemApril 18, 2024BRAZILIAN RESEARCH …
Field Testing of New HLB-Tolerant Scions and Rootstocks
By Rhuanito S. Ferrarezi, Jude W. Grosser, Fred G. Gmitter, Ed Stover and Kim Bowman Citrus is Florida’s most important agricultural commodity. The state produces citrus for different markets: round oranges for juice; navels, mandarins, grapefruit and lemons for the fresh-fruit industry; and lemons for extracting peel oil for processing. Huanglongbing (HLB) disease affects all citrus varieties. Since the discovery …
Some Rootstocks Succumbed to Irma
Researchers inspecting their groves at the Southwest Florida Research and Education Center after Hurricane Irma found that trees on certain rootstocks were very likely to be uprooted. Fernando Alferez, a horticulturist at the Immokalee center, discusses the uprooted trees and hopes he has for fresh citrus growing. “This is anecdotal evidence from our experience here,” Alferez says. “What we saw …
Rootstocks and HLB Tolerance — Another Perspective
By Ute Albrecht Tolerance to a disease is generally defined as the ability to be productive in the presence of disease-causing organisms. This is contrary to resistance, which is defined as the ability to completely evade a pathogen due to specific resistance mechanisms. The question as to what defines an HLB-“tolerant” rootstock was posed in an article by Bill Castle, …
Field Trials of Rootstocks and Scions: What Can They Tell Us?
By Harold Browning Column sponsored by the Citrus Research and Development Foundation Plant breeding programs have been a mainstay of citrus production worldwide. They have served as a basis for gradual improvement in fruit quality, adaptability to varying growing environments, and most importantly, to disease management. For that reason, new germplasm has been a front line of pursuit in the …
HLB and ‘Tolerance’ as a Practical Matter in Choosing Rootstocks
By Bill Castle (Editor’s note: Click on the graphs throughout the article to enlarge them.) By classic biological definition, a particular citrus rootstock-scion combination when infected with Candidatus Liberibacter asiaticus (CLas) would be considered tolerant if infected trees had no more than slight reductions in performance, sometimes accompanied by a reduced level of the pathogen. That definition implies that the …
Determining Planting Density
As growers grapple with planting new blocks in the HLB era, there has been considerable discussion about planting densities to optimize growth and yield. John Chater, assistant professor of horticultural sciences with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), has been working with growers in evaluating new varieties and rootstocks as trees are planted. TRENDING HIGHER …
Growing Citrus With Soil Health in Mind
Herb Young enjoyed a 40-year career in the agricultural chemical industry, starting as a technical service representative and eventually becoming a product manager. During those years, he worked on various specialty crops across the country. About 25 years of his career was spent in field research roles. So, experimentation with crops and growing practices comes naturally to Young. He has …
Surviving to Fight Another Day
Bill Lennon is working with researchers to learn more about survivor trees that are standing up to HLB. Bill Lennon is a fifth-generation citrus grower who can recall the industry’s glory days when Central Florida had hundreds of thousands of citrus acres before the 1980s freezes pushed production southward in the state. But he’s remained dedicated to the area, managing …
Factors Influencing Cold Hardiness of Citrus
Jake Price, University of Georgia county Extension coordinator, recently reported on the factors that influence cold hardiness of citrus. Excerpts follow: VARIETY The most obvious factor is the variety of citrus. In order of cold hardiness, the three main classes of citrus are mandarins, sweet oranges and grapefruit. Acid types of citrus such as lemons and limes are the least …
New Results From Owari Rootstock Trial
By Jake Price Rubidoux is considered the standard rootstock for Georgia, but it was not obtainable from U.S. Department of Agriculture (USDA)-certified nurseries in Florida in 2014 and 2015 because it is not a rootstock used in Florida. It is a proven rootstock in Georgia known for cold hardiness but did not perform well in a multiyear trial. The chart shows …
CRDF Off to a Busy Start in 2024
The Citrus Research and Development Foundation (CRDF) kicked off the new year with a full agenda for its monthly board meeting. New members were welcomed to the board. Growers Matt Machata, Sarah Spinosa and Trevor Murphy joined the group. On the research front, the board funded continued work by Ping Duan, a plant pathologist with the U.S. Department of Agriculture. …
Sneak Peek: February 2024 Citrus Industry
The February issue of Citrus Industry magazine takes a look at efforts to combat HLB. Some strategies are already available for growers to implement in their groves, while others offer hope for long-term solutions. The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) recently launched a new Crop Transformation Center. The goal of the center is to use …
Taking Available Tools to the Grove
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 & …
Florida Citrus Industry Survey Reflects Industry Optimism
By Frank Giles Last year’s citrus season was marred by continuing production declines from HLB and hurricanes. The combined effect of both dropped the final all-orange output to 15.8 million boxes. Certainly, the numbers reflected the dire situation the industry found itself in after the storms. But after last year’s harvest, growers were given clearance to utilize new trunk-injection therapies …
Updates on FDOC Research Projects
Florida Citrus Commission (FCC) members on Jan. 17 heard an update on one recent Florida Department of Citrus (FDOC) scientific research project and learned about some future research plans. Rosa Walsh, FDOC director of scientific research, presented the information. PROGRAM FOR EXPEDITED PROPAGATIONWalsh reported that the 2022–23 Program for Expedited Propagation of HLB Tolerant and Resistant Trees was successful. She …
CITRUS NURSERY SOURCE: Seeds Aplenty
By Peter Chaires Beginning this month, Citrus Nursery Source (CNS) transitions to Citrus Industry magazine after 14 years in Florida Grower magazine. For those unfamiliar with this column, CNS covers citrus industry issues that are of potential interest to nurseries and the growers they serve. Recognizing that it is difficult for nursery owners and staff to regularly attend meetings, this …