Massive Research Project in Millennium Block

Researchers at the resurrected Millennium Block at Fort Pierce will assess the performance of new grapefruit cultivars and evaluate numerous rootstocks in the face of HLB. University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researcher Rhuanito “Johnny” Ferrarezi discusses the history of the block and research planned there.

The block is called Millennium because some researchers planted variety trials there in the early 2000s, Ferrarezi says. The block was destroyed during a citrus canker eradication program around 2005.

A few years ago, “We started with the idea of having a large-scale variety trial here in the Indian River with massive support from our citrus industry and particularly the Indian River Citrus League and researchers from UF/IFAS and USDA (U.S. Department of Agriculture),” Ferrarezi says. The Millennium Block is on UF/IFAS Indian River Research and Education Center property. The USDA’s U.S. Horticultural Research Laboratory is next door.

Ferrarezi says he believes the project is “the largest grapefruit variety trial that we ever put together here.” Nineteen grapefruit varieties will be grown on three rootstocks, for a total of 57 combinations. Scientists expect to do research on about 24 acres of grapefruit, mandarins and navel oranges for the fresh market. Numerous rootstocks used with the grapefruit, mandarin and navel varieties will be evaluated.

“It’s quite interesting to see so many combinations planted side by side,” Ferrarezi says. “We are definitely seeing some trees growing more than others.” Researchers are also already seeing some “major differences” between varieties on different rootstocks, he says. Researchers are evaluating primarily UFR rootstocks developed by UF/IFAS but are comparing them to rootstocks that have been around for many years. “And we are also testing rootstocks from California, too, to see how they perform here in Florida,” he adds.

The project, funded by the Citrus Research and Development Foundation, will last at least six years, including three non-fruit-bearing years and at least two fruit-bearing years. The objective, Ferrarezi says, is “to pick the (scion and rootstock) winners and indicate perhaps the ones that are not that tolerant (of HLB) here.”

This interview with Ferrarezi is featured in June’s All In For Citrus podcast, a joint project of UF/IFAS and AgNet Media. Listen to the full podcast here.