UF Researchers Release Possible Citrus Greening Solution

Aug 21, 2015

University of Florida researchers think they found a way to help Florida’s embattled citrus industry-- it's been devastated by the citrus greening disease. The solution is a variety of trees that growers want and scientists don’t know much about.  

Citrus trees are really two trees in one: the bottom part is called the root stock and the top is what bares the fruit. About five years ago, University of Florida horticultural professor Fred Gmitter and his colleagues noticed some citrus root stocks were more tolerant of citrus greening. That doesn’t mean they're resilient-- they were still infected, but they managed to produce healthy fruit.

Gmitter said it usually takes 20 to 30 years of testing before he makes prototypes available. That’s because he’s looking for weaknesses in the root stocks. They could be susceptible to other diseases or sensitive to soil and to weather conditions. But he said commercial citrus growers were so desperate they asked UF to release 17 varieties of these root stocks.

"I can remember one day, I was in the grove talking with a grower and he said, 'I want that root stock. I want to plant 100 acres next year. I wana use that.' And I said, 'You know, I really don’t know anything about it. I don’t know how well it's going to yield.' And he looked at me and he said, 'Doc, look at that tree it has fruit on it that's yield,'" said Fred Gmitter. 

He said this may be a temporary way to keep the citrus industry from collapsing. Gmitter thinks there will eventually be trees that are resilient to citrus greening, but he said it won’t be any time soon. For now, growers are planting the more tolerant roots stocks. Gmitter expects tens of thousands of these kinds of citrus trees to grow in Florida within the next two years.