Citrus greening is a disease that has killed thousands of acres of orange and grapefruit trees across Florida, but there may soon be a solution to save the state’s signature crop in the form of exotic Australian fruit. 

The Australian finger lime is native to rainforests in Australia and resembles a pickle. The fruit is only a couple inches long and related to oranges but is impervious to citrus greening. Researchers at the University of California Riverside have been looking into using the resistance naturally present in finger limes to save the Florida orange. 

About five years ago, researcher Hailing Jin discovered the gene in finger limes that makes the fruit tolerant to the disease. The fruit produces a peptide, a natural antibiotic that kills the bacterium responsible for citrus greening. Now, Jin is developing a way for the reproduced peptide to be injected into trees or sprayed on leaves. In clinical trials, the treatment has greatly reduced the symptoms of the disease. 

The disease has had enormous implications for the state’s agricultural industry. Orange production has decreased from nearly 300 million boxes in 2000 down to about 70 million boxes last year. A cure derived from the finger lime could save millions of jobs and prevent production from being rerouted to farms in Texas and California. 

The researchers have partnered with a biotech company, Invaio Sciences to market the antimicrobial compound and hope it will be approved by regulators and widely available to Florida farmers in the next couple of years. 

In the meantime, farmers are exploring other options such as new orange varieties, new rootstocks, and techniques like putting orchards in screened enclosures. The potential to make orchards resistant to greening is a huge solution for an agricultural industry facing potential demise.