Fred Gmitter: Slow Road to Fast Genetics

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 West.

He returned to Rutgers after several years’ absence to complete the fourth year needed to get his English lit degree. Needing only electives, he took horticulture classes. “All my life, I was interested in gardening,” he explains.

EMBRACING BREEDING
When he heard a preeminent fruit breeder speak on campus, his future became clear. “I said, ‘I totally get this,’” he recalls.

Enthralled with fruit breeding, Gmitter picked up his English degree and stayed at Rutgers to get a master’s degree in horticulture. Then he went straight to the University of Florida (UF) to earn a doctorate in horticulture specializing in plant genetics.

Shortly before defending his doctoral dissertation in 1985, Gmitter interviewed with UF citrus researcher Bill Castle, head of a committee searching for a new citrus breeder. He got the job and joined Castle, as well as the recently hired Jude Grosser, at the Citrus Research and Education Center (CREC) in Lake Alfred.

UF wanted Gmitter to develop new citrus varieties (scions and rootstocks), and that’s exactly what he wanted to do. With then-current breeding knowledge, it took 15 years to develop new varieties. So he worked to make the practice more efficient. “That translated to a lot of genetic research,” he says. He realized a new, faster means of citrus breeding was imminent. “The science was evolving,” he says.

“One of the joys of my career has been to witness the explosion in genetic and genomic technology that has allowed us to do things in my lifetime that were dreamed of at the beginning of my career,” Gmitter says. Over his more than three decades at the CREC, the time required to breed a new variety has shrunk dramatically. Gmitter’s work has contributed largely to that time shrinkage.

The end result of that speed-up is growers getting new rootstocks and scions much sooner than ever before. And that’s important to Gmitter. As New Varieties Development and Management Corp. (NVDMC) Executive Director Peter Chaires says, “He is committed to the success and well-being of the Florida citrus grower.”

CITRUS GENOME SEQUENCING
Shortly after scientists published the human genome sequence, an International Citrus Genome Consortium was formed in 2003 to sequence the citrus genome.

The first money appropriated for the effort came when Gmitter approached the Florida Citrus Production Research Advisory Council (FCPRAC), predecessor of the Citrus Research and Development Foundation. FCPRAC allocated $500,000. “This was the first financial investment in the world, and it came from Florida citrus growers,” Gmitter says. A few other countries then added funding for the effort that Gmitter led and coordinated.

“In 2011, we provided to the world the first publicly available citrus genome sequences,” Gmitter says. Those sequences were made from diploid sweet orange and a haploid of Clementine. “For anybody who’s doing any kind of genetic research on citrus, the genomic sequence is a fundamental tool of all scientific disciplines studying citrus,” Gmitter says. “That was a very important contribution to all citrus research.”

That breakthrough is one of Gmitter’s career highlights and a testament to his people skills. “What makes him especially valuable are his communication skills,” says Chaires. “Fred is equally at home whether speaking with a group of growers, nurserymen, children, politicians, scientists or homeowner fruit enthusiasts. Travel to any backwoods corner of the world where citrus is grown and you will find that they not only know Dr. Gmitter, they will refer to him as their American friend.”

Gmitter is also highly respected by his peers worldwide, says Nate Jameson, owner of Brite Leaf Citrus Nursery at Lake Panasoffkee. While attending the International Citrus Congress in Brazil in 2016, Jameson noticed that most presentations drew only half a room of listeners. When Gmitter spoke, “the room filled to standing room only,” then went back to half-full following Gmitter’s presentation, Jameson says, adding, “That’s a lot of respect.”

“He’s a forward-thinking geneticist who’s working his fanny off to find solutions to HLB,” Jameson adds.

NEW VARIETIES
Another major accomplishment for Gmitter is also a joint effort — the establishment of more than 30 new UF citrus scions and rootstocks in the past eight years. His partners are fellow CREC citrus breeders Castle and Grosser. Gmitter says some of those varieties “are beginning to gain traction in the industry.”

One new variety is Sugar Belle, a mix of sweet Clementine and Minneola, released in 2009. “It (Sugar Belle) really appears to be the most HLB-tolerant variety in Florida,” Gmitter says. Interestingly, HLB tolerance wasn’t even on the researchers’ minds when they developed Sugar Belle; they were just looking for an earlier-maturing, Minneola-type fruit. Now, Gmitter and Grosser are using Sugar Belle in breeding because it transmits HLB tolerance to some of its offspring. They are crossing Sugar Belle with more oranges in hopes of developing an HLB-tolerant juice orange.

“The varieties that our team has developed and released are becoming important for the future of the industry, particularly those that have evidence of tolerance of HLB,” Gmitter says. “And maybe our greatest accomplishments are yet to come.”

Gmitter now is spending much time on the all-important quest for HLB-tolerant or resistant trees. (See sidebar, “The search for the ultimate HLB solution.”) Although he’s 66, he plans to continue the quest indefinitely. “There’s too much left to do to retire,” he declares. “As long as I’m doing the right things, why retire?”