Fresh from the Field - Florida Focus July 25, 2008 - Fresh from the Field - Florida Focus

Duda expands celery variety offerings using DNA fingerprinting

Duda Farm Fresh Foods, Oviedo, Fla., has been granted two patents for new commercial celery varieties.

The new varieties, ADS-11 and ADS-2, come from more than 1,200 lines developed during company trials to create celery with the best flavor, texture, nutrition and appearance for Duda's retail and foodservice customers, according to a news release. ADS-11 and ADS-2 are currently in commercial production in Florida and California, says Donna Duda, communications specialist for Duda.

To protect its proprietary celery varieties, the company has adopted DNA "fingerprinting" technology.

"While the patent provides the strongest protection and grants legal recourse for the company against any person or entity caught working with our proprietary varieties, you have to be able to identify your varieties and your proof has to be clear-cut," says Larry Pierce, manager of seed research for Duda Farm Fresh Foods. "DNA testing and DNA markers are the strongest proof."

The DNA system used by Duda allows the company to identify its varieties on the grocery store shelf, rather than testing the seed.

The newest patented celery varieties — both received in the spring — join six other celery patents in addition to five celery Plant Variety Protections. The company has six additional celery variety patents pending.

Black plastic mulch best defense against nutsedge

Weed-control experts Yasser Shabana, right, and Raghavan Charudattan of the University of Florida’s plant pathology department, check tomato beds at UF’s Plant Science Research and Education Unit, Citra, in a project aimed at controlling nutsedge, one of the world’s most troublesome agricultural weeds. UF/IFAS photo by Thomas Wrighty

University of Florida researchers found that black plastic mulch performed better than five other mulch varieties at suppressing nutsedge in tomatoes. The findings were presented at the 5th International Weed Science Congress, held June 23-27 in Vancouver, British Columbia. Nutsedge is among the world's most problematic agricultural weeds, and it affects virtually every crop grown in Florida.

The study was part of a project aimed to develop a nutsedge suppression system using hay infested with the fungal biocontrol agent Dactylaria higginsii, which kills nutsedge, says senior author Yasser Shabana, program manager of weed biocontrol at UF's plant pathology department, part of the University of Florida Institute of Food and Agricultural Sciences, Gainesville. The strain of Dactylaria higginsii used in the research was discovered by a UF graduate student, who has received two U.S. patents.

Shabana and colleagues at UF/IFAS, the U.S. Department of Agriculture and the University of Puerto Rico evaluated the mulches, using raised beds planted with tomato seedlings and purple and yellow nutsedge tubers, according to a University news release.

Black plastic mulch performed best, followed by green sorghum, green millet and cogongrass hay mulches, Shabana says. Cogongrass hay best suppressed tuber formation in both purple and yellow nutsedge. The researchers tested two plastic mulches, four green mulches and 10 organic hays for their ability to suppress the weed.

The research was partly funded by the USDA's Tropical and Subtropical Agricultural Research program.

Next year, researchers will evaluate combinations of plastic mulch and hay, some of which will be treated with the fungus, Shabana says. The goal of the study is to determine the combination that best discourages nutsedge, while providing mechanical barriers against any nutsedge plants that emerge.