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, …
Time to Get Serious About Trialing New Scion/Rootstock Combinations
By Jude W. Grosser and Frederick G. Gmitter It’s no secret that citrus greening disease, or HLB, continues to take a heavy toll on the beloved Florida citrus industry. It has been estimated that the industry will need to replant over 3 million trees per year for the next 10 years just to get back to normal. So the million-dollar …
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 Root Longevity
University of Florida Institute of Food and Agricultural Sciences plant pathologist Evan Johnson tells how drastically HLB harms citrus tree roots and suggests some ways to prolong root longevity and improve tree health. “It (HLB) causes very substantial root loss, up to between 30 and 50 percent early in the disease process from before visual symptoms are present to early …
Letter to the Editor: The Future of the Florida Citrus Industry*
By Bill Castle University of Florida professor emeritus Paul Genho, a former manager of the Deseret Ranch in Osceola County, spoke about soils and food at a Florida land conference in 2015.** He noted that 90 percent of the world’s food production occurred on only four soil types: Mollisols, Alfisols, Ultisols and Oxisols. A goodly proportion of those soil types …
Nurseryman Discusses HLB and Replanting Choices
As a member of a grower panel at the recent Florida Citrus Show in Fort Pierce, nurseryman Nate Jameson shared his thoughts on coping with HLB, choosing trees for replanting and more. The owner of Brite Leaf Citrus Nursery summarizes his presentation, starting with questions growers have for nurserymen. “I think the number-one question that we get is, ‘What tree …
Review of Fast Track for Fresh Selections Summarized
Peter Chaires, executive director of New Varieties Development & Management Corp. (NVDMC), summarizes a January 5 meeting seeking input on the Fast Track program. Fast Track lets citrus growers and nurseries access experimental University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) fresh citrus selections much earlier than was previously possible. Fast Track was co-developed by NVDMC, UF/IFAS and …
Grower/Nurseryman Suggests Fast Track Changes
Nurseryman and citrus grower Phil Rucks was one of several industry members offering input on the Fast Track program on January 5 at the Citrus Research and Education Center in Lake Alfred. Fast Track lets citrus growers and nurseries access experimental University of Florida/Institute of Food and Agricultural Sciences (UF/IFAS) fresh citrus selections much earlier than was previously possible. Among …
Hunt on Orange Production: Recovery Could Come Quickly
Florida Citrus Commission Chairman Ellis Hunt Jr. reacts to projections Wednesday that Florida’s orange production will likely be near current levels or possibly much lower in 10 years. He says existing growers and/or institutional investors could replant trees lost to HLB fairly rapidly if they believe trees can survive and produce fruit in the face of HLB. “I think we …
Planting New Groves in the Face of HLB
Planting new groves in the face of HLB has become a daunting task for Florida growers. At the recent Citrus Expo, University of Florida researcher Ute Albrecht offered suggestions for those taking on the challenge. “Among the important things to consider when planting new groves are the site preparation, the planting of the trees, weed management, irrigation and nutrition, and …
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 …
Moving Murcott from the Top of the Tree to the Bottom
By Bill Castle and Luiz A.B.C. Vasconcellos Maybe it’s time to try a scion as a rootstock! Murcott is widely known as a scion variety, but it might be an interesting rootstock based on grower experience in Brazil as well as rootstock trial results and some commercial use in Florida. Mandarin rootstocks and their hybrids have generally good horticultural traits, especially …