It’s this fourth generation of transgenic trees that Mirkov said will likely be taken through the lengthy and costly deregulation process that declares the fruit safe to eat.

“It’s an expensive process that involves contracts with firms that do the actual testing with rats, bees, an aquatic invertebrate, maybe a songbird,” he said. “It could take three to four years to complete, but it’s important to determine that the fruit produced from transgenic trees are safe to eat, especially by what are considered at-risk groups, which include infants, the elderly and those with compromised immune systems.”

That’s also the reason Mirkov works only with genes and proteins found in foods.

“I decided seven years ago when this program started that if the proteins were not commonly eaten, we wouldn’t work with them.”

Mirkov’s transgenic work in citrus currently includes Rio Red and Ruby Red grapefruits, Hamlin and Marrs sweet oranges, Rhode Red Valencia oranges and three rootstocks: Flying Dragon, C22 and Carrizo.

Mirkov said he meets several times a year with federal agencies to keep them abreast of his progress. They include the Food and Drug Administration, the Environmental Protection Agency and the U.S. Department of Agriculture.

“There are lots of regulations and requirements to meet, but without immunity to citrus greening, the entire world’s citrus industry is at risk. Citrus greening is a citrus grower’s worst nightmare because at this point, there is no cure. It can spread for years before it can be detected, so it’s insidious, to say the least.”

Ray Prewett, president of Texas Citrus Mutual, a commodity group in Mission, Texas, said Mirkov’s work is important and promising.

“The majority of the support for Mirkov’s research has come from Florida, but the Texas citrus industry has provided some financial support as well,” he said. “The entire U.S. citrus industry is placing a lot of hope and faith on the outcome of this research. Our industry is using all of the currently available tools to fight the disease recently found in Texas, but we are counting on disease-resistant trees as our best long term solution.”

California citrus growers have a “great opportunity” to learn from what happened in Florida and react accordingly, says Cress.

Dreyer, who farms 1,000 acres of citrus in Tulare County, said the Florida message is clear.

“We need more research now,” said Dreyer, a member of the California Research Board, which is directing the green disease research effort in the state.

As devastating as HLB is, he does not expect a panic when that first infected commercial tree or grove is detected.

Dryer said the treatment protocol developed by University of California scientists “should be very effective.”

“Controlling the psyllid will fit into our current cultural and pest control practices. We may have to treat at a different times than we normally do now to control the psyllid during the period of lush green growth when we do not treat now,” he said.  There are no known pesticides to combat the disease. It can only be eliminated by finding and eliminating the insect carrier.

Infected trees and those nearby should be removed quickly after a disease confirmation. Treatments will follow. Dryer says for now, the critical research need is to find new materials to control the psyllid in case resistance becomes a major issue. “We have the tools to control the psyllid now, but we could eventually face a resistance issue and need more material.”

The stakes are high, especially in the wake of the past couple of years for California citrus growers. “Growers have had a lot of financial success the past few years. Fortunately, we have some very good areas that are conducive only for citrus, and not almonds or some other crops. It is a banana belt that runs along with eastern area of the valley.”