Plant Biostimulants — Snake Oils or Beneficial Substances?

Tacy CalliesBiostimulants

By Ute Albrecht and Sarah Strauss Recent years have seen an explosion of products termed “biostimulants” as alternatives to traditional chemical products to improve plant growth and productivity, and to enhance the sustainability of agricultural systems. Although there is currently no legal definition of biostimulants, they are usually defined as “substance(s) and/or microorganisms that when applied to plants or the …

HLB

Millennium Block Resurrected for HLB Research

Ernie NeffGrapefruit, HLB Management

An approximately 35-acre research plot that fell victim to citrus canker years ago will soon become a new research site helping growers pick trees that fare best with HLB. The plot at the Indian River Research and Education Center (IRREC) in Fort Pierce will keep its former name, the Millennium Block. University of Florida Institute of Food and Agricultural Sciences …

Agenda

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science

See Science in Action at CREC’s 100th Anniversary Celebration

Daniel CooperCitrus, Industry News Release, Research

Oranges, grapefruit, tangerines and limes. Most people think of these as signature plants of Florida, but scientists have traced their origins back millions of years and across continental land masses, said Fred Gmitter, a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) professor of horticultural sciences. Scientists can describe the evolutionary paths of your favorite citrus, from prehistoric …

Progress on Engineering HLB-Tolerant/Resistant Citrus

Tacy CalliesVarieties

By Manjul Dutt and Jude W. Grosser Huanglongbing (HLB) threatens the survival of the Florida citrus industry. Both conventional cultivars and genetically engineered cultivars that can grow in the presence of HLB have been developed at the University of Florida’s Citrus Research and Education Center (CREC) in Lake Alfred. Among the two citrus improvement techniques, engineering citrus remains the fastest …

A Look Back at 100 Years of Citrus Innovation

Tacy CalliesHistory

By Beverly James, Alec Richman, Brad Buck, Samantha Grenrock and Tom Nordlie The year was 1917. In April, the United States entered World War I. Florida’s population was fast approaching 1 million, and agriculture was the state’s most important economic driver. Citrus cultivation, introduced to Florida 400 years earlier by Spanish explorers, had spawned an industry following the Civil War. …

Greatest CREC Accomplishments

Tacy CalliesResearch

Editor’s note: This article is part of the special coverage on the 100th Anniversary of the UF/IFAS Citrus Research and Education Center, found in the October 2017 issue of Citrus Industry magazine. By Tom Nordlie Throughout the Citrus Research and Education Center’s (CREC) 100-year history, the collective efforts of its faculty and staff have supported Florida citrus growers in myriad …

Citrus Production in Argentina

Tacy Callieslemons

By Stephen H. Futch and Ariel Singerman In May of 2017, we visited the northwestern citrus production region of Argentina in the provinces of Jujuy, Salta and Tucumán. The purpose of the trip was to learn more about Argentina’s citrus industry and programs being developed to deal with both the Asian citrus psyllid (ACP) and huanglongbing (HLB). Argentina has a …

HLB

Bactericides, Psyllids and HLB-Resistance/Tolerance

Ernie NeffBactericides, HLB Management, Psyllids

At a recent meeting of the Citrus Research and Development Foundation’s (CRDF) Commercial Product Delivery Committee, approximately half of the agenda was devoted to bactericides and HLB-spreading psyllids. Reflective mulch that keeps psyllids away and field trials for HLB-resistant or tolerant rootstocks and scions were also addressed. CRDF Chief Operations Officer Harold Browning summarizes some of the discussions. “The issue …

Time to Get Serious About Trialing New Scion/Rootstock Combinations

Tacy CalliesRootstocks, Scions

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 …

Fred Gmitter: Slow Road to Fast Genetics

Tacy CalliesBreeding, Citrus

By Ernie Neff Even Nostradamus would have struggled to predict a career path for a 25-year-old Fred Gmitter. Gmitter had quit college after three years at Rutgers University, where he studied English literature with plans to teach. He said he “became completely disillusioned” with that plan. He married, worked as a delivery truck driver and warehouse laborer, and traveled out …

HLB

Older Trees and Older Growers

Ernie NeffCitrus, HLB Management

Florida’s older citrus trees are disappearing due to HLB and other problems, and the most prominent varieties being grown haven’t changed in many decades. Additionally, many long-time growers are nearing retirement. Those were among topics raised at a recent grower forum in Sebring. Laurie Hurner, Highlands County Extension director and citrus agent, hosted the meeting and summarizes discussions of aging …

Citrus Expo

What Have We Learned?

Tacy CalliesCitrus, News from our Sponsor

By Harold Browning Column sponsored by the Citrus Research and Development Foundation Within the Citrus Research and Development Foundation (CRDF), the daily challenge of keeping up with a wide array of HLB topics, more than 75 currently funded projects, and monthly committee and board meetings translates into a constant flow of information. Project managers meet weekly to discuss progress and …

Controlled-Release Fertilizer Boosts Health of HLB Trees (Part 2)

Tacy CalliesCitrus, Nutrition

By Pete Spyke, Joby Sherrod and Jude Grosser Part 1 of this article, published in the April 2017 issue of Citrus Industry magazine, provided some background information on controlled-release fertilizer (CRF) along with a discussion of practical applications in citrus production. This article, part 2, includes summaries of observations from several case studies in which CRF has been applied for …

Insight on Improved Management of HLB-Affected Trees

Josh McGillIrrigation, Nutrition

Recent studies shed light on foliar nutrient and irrigation practices. By Kelly T. Morgan and Said Hamido Most citrus growers are well aware that citrus greening (HLB) is one of the most devastating citrus diseases in many parts of the world. The disease is widespread in Florida, Texas, Brazil, Mexico and other major production areas, causing significant concerns about the …

Why Bicarbonates Matter for HLB Management

Josh McGillNutrition

By Jim Graham and Kelly Morgan Huanglongbing (HLB), greening and yellow shoot are names for the most devastating citrus disease in the world. Symptoms of HLB include a distinctive chlorotic mottle on fully expanded leaves. Infected shoots are stunted, and branches gradually die back as the symptoms appear in other sectors of the tree canopy. HLB reduces fruit size, weight …

Growers

What Growers Say and Hear at Mutual Meetings

Ernie NeffBactericides, Legislative

Florida Citrus Mutual has been cooking for its grower members, hearing what’s on their minds and telling what the association is doing for them at area meetings this spring. At a recent meeting in Bartow, Mutual CEO Mike Sparks summarized what growers are talking about, and what Mutual is telling the growers. “The entire citrus industry knows we’re still in …

Searching for Citrus Varieties Resistant to HLB

Len WilcoxCalifornia Corner, Research

Three old trees at the Lindcove Research and Extension Center (REC) might hold the key to huanglongbing (HLB) resistance, according to an article in the University of California (UC) publication California Agriculture. The Lindcove REC is located on the eastern edge of the San Joaquin Valley near Visalia, California. Several of the citrus varieties tested at Lindcove REC were bred …

Safeguarding Citrus Stock

Tacy CalliesCitrus Greening, Regulation

By Georgios Vidalakis On March 30, 2007, I received a memorable phone call in my office at the University of California (UC), Riverside. “Georgios,” said the caller, “The 2008 Farm Bill will establish the National Clean Plant Network (NCPN) for specialty crops. This program will be like no other because it will be driven from the ground up. The system …

Finger Lime Could Be New Crop for Citrus Growers

Tacy CalliesBreeding

By Manjul Dutt, Ethan Nielsen and Jude Grosser The finger lime is a citrus relative, scientifically named Microcitrus australasica. Finger limes are native to Australia and are so named because the fruits are long and fingerlike in shape (see figures 1 and 2). Finger limes belong to a group of similar citrus relatives, all originating from Australia with common names …