Indian River Millennium Block Shows Rootstock Effects

Tacy CalliesRootstocks

By Rhuanito S. Ferrarezi, J. Martin Zapien-Macias, Mac Hossain, Tom James, Ronald D. Cave, Peter Spyke, William S. Castle, Jude W. Grosser, Fred Gmitter and Ed Stover In the last decade, huanglongbing (HLB) has reduced production of Florida grapefruit by 75%, mandarin by 78% and sweet orange by 52%. This decrease is significant for the Indian River District, which produces … Read More

Valencia Performance and Rootstock Propagation Methods

Tacy CalliesRootstocks

By Ute Albrecht, Sameer Pokhrel and Kim D. Bowman According to the 2019–2020 Citrus Budwood Annual Report, there were 772,391 (20%) rootstock propagations from tissue culture and 224,346 (6%) from cuttings out of the 3.9 million total propagations that season. The report is from the Florida Department of Agriculture and Consumer Services. This unprecedented high number of vegetative (not from … Read More

Sneak Peek: July 2021 Citrus Industry

Tacy CalliesRootstocks, Sneak Peek, Varieties

Growers looking for advice on the subjects of rootstocks and varieties will find several pertinent articles in the July issue of Citrus Industry magazine. According to University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) citrus breeder Jude Grosser, Orie and Louise Lee (OLL) oranges are giving Valencias a run for their money. He discusses the beneficial characteristics of … Read More

The Secret Ingredient of Developing New Citrus Rootstocks

Tacy CalliesCitrus, Rootstocks

By Bill Castle Creation, evaluation, release and commercial acceptance are dynamic, interactive activities that together constitute new rootstock development. Underpinning each of them is a commonly overlooked and rarely mentioned activity, professional judgment. Yet, it is something everyone has and recognizes as getting better with time and experience. It is a skill developed and refined over time from knowledge of … Read More

Florida Growers Wanted for Rootstock Trials

Ernie NeffResearch, Rootstocks

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 … Read More

Georgia Owari Rootstock Trial Update

Ashley RobinsonGeorgia, Rootstocks

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 … Read More

Georgia Trials Offer Rootstock Choices

Ernie NeffRootstocks

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 … Read More

Choosing a Lemon Rootstock

Tacy Callieslemons, Rootstocks

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 … Read More

Varieties and Rootstocks Reviewed

Ernie NeffRootstocks, Varieties


In his virtual Citrus Expo presentation, Jude Grosser reviewed varieties and rootstocks showing promise for productivity in the face of HLB. Grosser is a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) plant breeder. His presentation was based on work done by him and fellow UF/IFAS researchers Bill Castle and Fred Gmitter. Grosser said UF/IFAS released OLL-20 “based … Read More

Long-Term Rootstock Evaluation Is Best

Ernie NeffRootstocks

A variety of different findings in recent rootstock trials led to a conclusion that long-term evaluation of rootstocks is necessary to assess economic benefits to growers. That conclusion was part of a take-home message in Ute Albrecht’s virtual Citrus Expo presentation. Albrecht is a researcher with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS). Her report was … Read More

Rootstock and Scion Affect Orange Juice Flavor

Tacy CalliesRootstocks, Scions

By Yu Wang, Fred Gmitter and Jude Grosser A major concern for the citrus industry is a significant decline in production due to huanglongbing (HLB). In addition to the production shortfalls are losses due to fruit rejection by packinghouses and juice processing plants as a result of inadequate size and low sugar content. Bitterness and metallic off flavors in the … Read More

Rootstock Offers High Hopes for HLB Tolerance, Maybe Resistance

Tacy CalliesRootstocks

The new Sugar Belle hybrid rootstock LB8-9xS13#16 has quite a history, according to University of Florida Institute of Food and Agricultural Sciences citrus breeder Jude Grosser.  “This is one of several projects I did with Orie Lee toward the end of his Florida Citrus Hall of Fame career/life,” recalls Grosser. “We did a lot of brainstorming together, and he was … Read More

New Rootstocks in the Citrus Breeding Pipeline

Tacy CalliesResearch, Rootstocks

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 … Read More

Rootstock Effects on Valencia and Hamlin in Large-Scale Commercial Plantings

Tacy CalliesResearch, Rootstocks

By Ute Albrecht, Sudip Kunwar and Jude Grosser Prior to 1865, the only rootstocks used in Florida were sour orange and sweet orange. Use of grafted trees instead of seedling trees became necessary because of the devastating effects of phytophthora on sweet orange. Sour orange was widely used as a rootstock because of its resistance to phytophthora and other positive … Read More

How to Use the New Florida Citrus Rootstock Selection Guide

Tacy CalliesRootstocks

By Rhuanito S. Ferrarezi, William S. Castle, Kim D. Bowman, Jude W. Grosser, Stephen H. Futch, Steve Rogers and Andres Gonzalez First published in 1989 as Rootstocks for Florida Citrus, the work of William Castle and his colleagues remains relevant 30 years later. The purpose of the fourth edition of the Florida Citrus Rootstock Selection Guide is to provide timely … Read More

Lessons Learned From Rootstock Field Trials

Tacy CalliesResearch, Rootstocks

By Bill Castle “The notion that field trial data are of little value in the early years and trials must run for 15 years is outdated.”  [Lesson 7] “Our new website provides the grower community with user-friendly access to our collective decades of rootstock trial data…” [Lesson 9] Those are two of many lessons shared in a recent article authored … Read More

Rootstock Trial Results on New Website

Tacy CalliesRootstocks

A new website with a wealth of information about citrus rootstocks is now available at Rootstock breeder Kim Bowman, with the U.S. Department of Agriculture (USDA) Agricultural Research Service in Fort Pierce, has posted results from 37 replicated multiyear rootstock field trials in Florida. The results can be easily accessed from the site by computer, tablet or smartphone.  According … Read More

Rootstock Selection Made Easier

Ernie NeffRootstocks


The recently released fourth edition of the Florida Citrus Rootstock Selection Guide is “way more user friendly” than past editions, one of its authors says. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researcher Rhuanito “Johnny” Ferrarezi says “a completely redesigned website” is what makes the guide so useful for growers. Ferrarezi works as an assistant professor at … Read More

Some Scions Incompatible With US-1283 Rootstock

Daniel CooperIndustry News Release, Rootstocks


By Kim D. Bowman and Ute Albrecht The US-1283 rootstock was released by the U.S. Department of Agriculture (USDA) in 2014, based on field performance with Hamlin 1-4-1 sweet orange in trials at two different locations in Florida severely affected by huanglongbing disease. One of these trials was in St. Lucie County and of 14 years duration, while the second … Read More

Thoughts on the Scion and Rootstock Selection Process

Tacy CalliesRootstocks, Scions

By Bill Castle If timing is everything, then let me suggest that the timing is right to consider the following proposals about making scion and rootstock choices in the Florida citrus industry: What to plant? That is a huge question that could be initially addressed by a one-day program carefully planned as to objectives, format and participants. I was reminded … Read More