Agri Leader

UF researchers closing in on compact growth tomato

After years of preliminary effort, researchers at the University of Florida believe they will eventually be able to breed a new variety of so-called "compact growth" tomato that can be mechanically harvested.

Success in doing that would revolutionize tomato production by making it more efficient and significantly reducing costs, primarily by lowering labor costs.

The latest phase of the initiative, sponsored by Florida Specialty Crop Foundation (FSCF), will be funded by a two-year, $306,762 USDA specialty crop block grant administered by Florida Department of Agriculture and Consumer Services.

The next phase of the ongoing project, set to get underway Jan. 1, represents "a major shift in concept from current production processes for field grown tomatoes," said Sonia Tighe, FSCF's executive director. "The cost of tomato production is now almost prohibitive, even for our largest producers," Tighe said. "So it is critical that we find a better way to be able to produce a crop and get it out of the field at reduced costs, including [less spent on] pesticide applications, inputs, carbon footprint and labor."

Samuel Hutton, assistant professor, tomato breeding and genetics, at UF's Horticultural Sciences Gulf Coast Research Center in Wimauma, said he and his colleagues now believe they can successfully develop a compact growth tomato that can be harvested by machine.

"The impact that could have would be incredible in terms of the cost savings, especially with regard to labor, that growers could realize," Hutton said. "In addition to reduced labor costs, growers would not have the costs currently related to things like stringing and tying."

The production season could also be shortened, Hutton said, and result in a once-over harvest, as opposed to multiple, ongoing harvesting cycles that exist today. And a shorter season means more savings, because the costs of water, fertilizer and pesticides would also be reduced.

Equipment currently used to process tomatoes - primarily plum and roma varieties - must be adapted for mechanical harvesting, Hutton explained, since relatively limited market demand would make R&D of a new machine prohibitively expensive. UF researchers are currently working with an existing equipment manufacturer to extend the use of its technology to harvesting.

"First we have to develop a variety of tomato that can be mechanically harvested," Hutton said. "Then we have to adapt existing processing machinery to be able to harvest that tomato."

Development of a compact growth tomato that can be mechanically harvested would extend and strengthen Florida's reach in the commercial marketplace.

Florida ranks first in the U.S. in fresh-market tomato production, with a market value of $267 million in 2012, according to USDA data. For the season, Florida had the second largest fresh-market tomato acreage in the United States, with 29,000 acres harvested and an average yield of 33,000 pounds per acre resulting in almost a billion pounds of fruit.

The concept of a machine harvestable fresh market tomato is not new. UF researchers released their first variety in 1971. Over the years, new work has increasingly focused on so-called compact growth tomatoes, which feature low growth and spreading characteristics that deliver a compact plant that holds fruit on shorter branches.

As a result, compact growth tomatoes do not require staking, tying, or pruning.

The process results in a plant approximately 24 inches in diameter, with a 50-60 percent reduction in internode length compared to staked upright varieties.

Current keys to commercial success, Hutton said, include a high level of fruit firmness and also jointless pedicels. Today, the vast majority of commercial tomatoes have a joint and the stem is pulled off by workers. "You're not going to have a worker available to be doing that if a machine is doing the harvesting, so you can't have those stems," Hutton said. "So, you have to have a jointless pedicel."

Another key is a good concentration of fruit set. "Most of the fruit has to get ready at about the same time if you're going to do a once-over harvest and maximize your yield," Hutton said.

Challenges include disease resistance and a final product that is up to current commercial market standards in terms of size, flavor and other traits, such as gray wall resistance, disease resistance and heat tolerance.

"The tomato will have to meet all the commercial criteria that are in the market now, such as firm fruit and a good yield," Hutton said.

Developing a commercially viable compact growth tomato that can be mechanically harvested remains a challenge, Hutton said.

But for the first time, UF researchers are guardedly optimistic they can meet the challenge and transform tomato production, which would further strengthen Florida's agricultural industry.