Rootstock/Scion Combos: What Works and What Doesn’t

Tacy Callies Rootstocks, Scions

By Ernie Neff For Phil Rucks and Tom Powers at Phillip Rucks Citrus Nursery in Frostproof, Florida, selecting rootstock and scion combinations starts by acknowledging that some varieties just don’t do well with HLB. “We don’t recommend some varieties regardless of rootstock,” Rucks says. Powers says varieties that are especially difficult to grow with HLB are Hamlin, midsweet and pineapple …

mandarin

Rootstock Choice May Be Key in Tree Productivity

Tacy Callies Rootstocks

Florida citrus growers recognize the Sugar Belle® mandarin hybrid for its tolerance of citrus greening disease, and new findings from the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) suggest that rootstock selection may play a role in keeping Sugar Belle® trees productive even if they become infected with the bacterial malady. “We now have proof of concept …

Field Testing of New HLB-Tolerant Scions and Rootstocks

Tacy Callies Research, Rootstocks, Scions

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 …

Alternatives to Rootstock Propagation by Seed: Differences, Concerns and Expectations

Tacy Callies Research

By Ute Albrecht Commercial citrus rootstock propagation traditionally occurs via use of nucellar apomictic seed, which generates genetically identical seedlings that are used as liners for budding. With the high demand for superior rootstocks in the age of HLB, commercial nurseries are currently experiencing a shortage of seeds for some of the most popular rootstock varieties. In addition, for many …

rootstocks

Some Rootstocks Succumbed to Irma

Ernie Neff hurricane, Rootstocks

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

Tacy Callies HLB Management, Rootstocks

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, …

Citrus Expo

Field Trials of Rootstocks and Scions: What Can They Tell Us?

Tacy Callies News from our Sponsor, Rootstocks, Scions

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

Tacy Callies 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 …

Improved Rootstock Selection Tool

Josh McGill Citrus, Citrus Greening

Florida Citrus Rootstock Selection Guide: New Custom Query Option The third edition of the Florida Citrus Rootstock Selection Guide was recently released online at flrootstockselectionguide.org and has now been expanded to include an expert system to aid growers in rootstock selection. The expert system was developed as a collaborative effort of Steve Rogers, Bill Castle, Steve Futch and Andrew Persaud. …

crdf

CRDF Board Passes Preliminary Budget and Funds Projects

Daniel Cooper CRDF

During its April meeting, the Citrus Research and Development Foundation (CRDF) board of directors passed its preliminary budget for the next fiscal year. It allows $1.4 million in new project funding. “This amount should be enough to fund the projects the board wishes to fund from our primary request for proposals, which are aimed at answering practical questions growers have …

diaprepes

Where to Watch for Diaprepes Root Weevil

Daniel Cooper Pests, Tip of the Week

By Larry Duncan Prior to the introduction of citrus greening disease in Florida, certain conventions applied to the occurrence and impact of diaprepes root weevil in groves across the state. The abundance and damage potential of this major pest were greatest in some Flatwoods habitats, such as parts of the inland East Coast where newly planted trees sustained major damage. …

georgia

Big Yields Expected in Georgia

Daniel Cooper Georgia, Production

A December 2022 freeze in Georgia significantly reduced the state’s 2023 citrus production, but many growers anticipate a large crop in 2024. “With less fruit production in 2023, trees added a lot more vegetative growth and increased their canopy volume,” University of Georgia Extension citrus agent Jake Price noted. “The satsuma bloom at the research plot was very large and …

climate

Kaolin and Climate Impacts on HLB Addressed

Daniel Cooper Events, HLB Management

The impacts of kaolin and climate on HLB in Brazil were among topics addressed by researchers from Brazil’s Fundecitrus during the recent International Research Conference on HLB in Riverside, California. HLB is also known as citrus greening. Researcher Marcelo Miranda discussed results of a study on the use of processed kaolin in low doses to reduce the HLB-spreading psyllid population …

owari

In Georgia Owari Trial, Yields Peaked in 2021

Daniel Cooper Georgia, Research, Rootstocks

University of Georgia Extension agent Jake Price recently summarized yields for three recent seasons from Owari satsuma trees in a rootstock trial. Last year, 2023, was the last harvest year for data collection in the trial. Price reported that yield in the trial plot peaked in 2021 with a yield of about 20,300 pounds on 60 trees, which would be …

hlb

Rigorous HLB Control Works at Brazilian Farm

Daniel Cooper Brazil, HLB Management

Fabrício Eustáquio Lanza, research coordinator at Brazil’s Cambuhy Agricola, recently told how his company has kept HLB at low and economically acceptable incidence levels. His presentation at the recent International Research Conference on HLB was based on a report he co-authored with Alexandre Tachibana, Ivan Brandimarte, Antonio Juliano Ayres and Renato Beozzo Bassanezi. The report follows: MANAGEMENT MEASURES Huanglongbing (HLB), …

planting

Determining Planting Density

Daniel Cooper Economics, planting

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 …

Citrus Congress

Fundecitrus Participates in Australian Citrus Congress

Daniel Cooper Events, International

General Manager Juliano Ayres and researcher Franklin Behlau of Brazil’s Fundecitrus participated in the recent Australian Citrus Congress. Attendees discussed the impacts caused by citrus greening in affected countries like Brazil and worked to establish strategies for preventing and detecting the disease in Australia. During the event, Behlau gave a lecture at the Citrus Australia Biosafety Symposium and provided an …

fresh

A Fresh Approach

Daniel Cooper CRAFT, Fresh, Packing

Despite the challenges of the Florida citrus industry, Feek Family Citrus continues to successfully grow, pack and ship fresh fruit. In an effort to discourage his son from working in the citrus business, Doug Feek’s father gave him all the worst jobs to do in the family’s small grove. “He wanted me to save my back and work a desk …

growing

Growing Citrus With Soil Health in Mind

Daniel Cooper Cover Crops, Georgia, Soil Health

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 …