Since 2006, the bacterial disease citrus greening has cost Florida’s economy an estimated $3.63 billion in lost revenues and 6,611 jobs by reducing orange juice production, according to a study from the University of Florida’s Institute of Food and Agricultural Sciences.

The study is the first complete assessment of greening’s economic impact on Florida, says Jack Payne, UF senior vice-president for agriculture and natural resources.

He called the study “an important step” in the fight against greening, because it quantifies damages and could show legislators and funding agencies why the invasive disease is one of the state’s biggest challenges.

“This study shows plainly just how imperative it is that we find a cure for citrus greening,” Payne says. “We have dedicated a huge amount of IFAS resources toward that end, and we are very appreciative of the significant support our research is receiving from the citrus industry.

“Growers are the people most obviously impacted, but the study demonstrates that many other Floridians are hurt as well — when fewer oranges are harvested, fewer dollars are circulating in our state’s economy.”

First detected in Florida in 2005, greening causes citrus trees to drop fruit prematurely and eventually kills the trees. The disease is caused by a bacterium, and was first described in 1919 in China. The bacterium is transmitted by an invasive insect, the Asian citrus psyllid.

The study compares actual harvests of oranges used to make juice with projected harvests that would have taken place if greening had never struck Florida groves; it covers the growing seasons from 2006-2007 through 2010-2011.

During those five years, the disease caused substantial crop losses, says Citrus Economist Tom Spreen, professor in the UF/IFAS food and resource economics department.

The state’s juice-orange harvest for the period was 734 million boxes, and would have been an estimated 951 million boxes without greening, Spreen said.

When focusing strictly on juice-orange production during that five-year period, Florida growers lost $1.36 billion in revenues, and 2,125 permanent jobs were lost.

Florida Citrus Mutual, the state’s largest citrus grower organization, funded the study. Florida is the nation’s largest citrus producer and the world’s second-largest orange juice producer, after Brazil. Florida’s citrus industry generates about $8.9 billion a year, mainly from orange juice production.

The study is available at http://edis.ifas.ufl.edu/fe903.